FASEB journal : official publication of the Federation of American Societies for Experimental Biology, Jan 25, 2018
Sepsis-leading to septic shock-is the leading cause of death in intensive care units. The systemi... more Sepsis-leading to septic shock-is the leading cause of death in intensive care units. The systemic inflammatory response to infection, which is initiated by activated myeloid cells, plays a key role in the lethal outcome. Macrophage migration inhibitory factor (MIF) is an upstream immunoregulatory mediator, released by myeloid cells, that underlies a common genetic susceptibility to different infections and septic shock. Accordingly, strategies that are aimed at inhibiting the action of MIF have therapeutic potential. Here, we report the isolation and characterization of tailorable, small, affinity-matured nanobodies (Nbs; single-domain antigen-binding fragments derived from camelid heavy-chain Abs) directed against MIF. Of importance, these bioengineered Nbs bind both human and mouse MIFs with nanomolar affinity. NbE5 and NbE10 inhibit key MIF functions that can exacerbate septic shock, such as the tautomerase activity of MIF (by blocking catalytic pocket residues that are critical...
Proceedings of the National Academy of Sciences, 2017
Significance The biological processes that are involved in the progression of multiple sclerosis ... more Significance The biological processes that are involved in the progression of multiple sclerosis (MS) are far from complete. Macrophage migration inhibitory factor (MIF) and its homolog, D-dopachrome tautomerase (D-DT), are immunoregulatory cytokines known to be involved in the worsening of various autoimmune disorders. We demonstrate that genetically controlled high MIF expression (and D-DT) promotes MS progression in males, suggesting that these two factors are sex-specific disease modifiers. In addition, we show that MIF or D-DT deficiency ameliorates the disease severity of the murine model of MS. Our data suggest that targeting CD74, the common receptor for MIF and D-DT, with therapies such as partial MHC class II constructs could be therapeutically beneficial for inhibiting MS clinical progression in selected patients.
Macrophage migration inhibitory factor (MIF) was first described as a cytokine 50 years ago, and ... more Macrophage migration inhibitory factor (MIF) was first described as a cytokine 50 years ago, and emerged in mammals as a pleiotropic protein with pro-inflammatory, chemotactic, and growthpromoting activities. In addition, MIF has gained substantial attention as a pivotal upstream mediator of innate and adaptive immune responses and with pathologic roles in several diseases. Of less importance in mammals is an intrinsic but non-physiologic enzymatic activity that points to MIF's evolution from an ancient defense molecule. Therefore, it is not surprising that mif-like genes also have been found across a range of different organisms including bacteria, plants, protozoa, helminths, molluscs, arthropods, fish, amphibians and birds. While Genebank analysis identifying mif-like genes across species is extensive, contained herein is an overview of the nonmammalian MIF-like proteins that have been most well studied experimentally. For many of these organisms, MIF contributes to an innate defense system or plays a role in development. For parasitic organisms however, MIF appears to function as a virulence factor aiding in the establishment or persistence of infection by modulating the host immune response. Consequently, a combined targeting of both parasitic and host MIF could lead to more effective treatment strategies for parasitic diseases of socioeconomic importance.
Chronic helminth infections are associated with modulation of host cellular immune responses, pre... more Chronic helminth infections are associated with modulation of host cellular immune responses, presumably to prolong parasite survival within the mammalian host. This phenomenon is attributed, at least in part, to the elaboration of parasite molecules, including orthologs of host cytokines and receptors, at the host-parasite interface. This review describes recent progress in the characterization of macrophage migration inhibitory factor (MIF) orthologs from parasitic nematodes. The roles of these molecules in parasite developmental biology and pathogenesis are discussed. Further knowledge of the species-specific activities and three-dimensional structures of human and parasitic nematode MIF molecules should make them ideal targets for drug-and/or vaccine-based strategies aimed at nematode disease control. Helminth immunomodulation At the host-parasite interface parasitic nematodes produce a panoply of molecules, both on the cuticular surface and/or released in excretory-secretory (ES) products, which mediate their ability to survive for long periods of time despite the actions of the host immune system [1]. These parasite mediators drive potentially immune-evasive processes that allow for the parasites' prolonged survival within their hosts [2]. There is functional diversity in these parasite-derived immune modulators that presumably reflects a long-standing coevolutionary relationship between nematode parasites and their respective hosts. Putative nematode virulence factors that might subvert host immune responses effectively include proteases, protease inhibitors, antioxidant proteins and orthologs of mammalian cytokines and their receptors [3]. Studies by several investigators have provided evidence of the elaboration by parasitic nematodes of macrophage migration inhibitory factor (MIF) orthologs, which modulate the taxis of immune cells, altering their gene expression and the subsequent production of cytokines.
Proceedings of the National Academy of Sciences, 2011
Macrophage migration inhibitory factor (MIF) is a pivotal regulator of the immune response. Neutr... more Macrophage migration inhibitory factor (MIF) is a pivotal regulator of the immune response. Neutralization or genetic deletion of MIF does not completely abrogate activation responses, however, and deletion of the MIF receptor, CD74, produces a more pronounced phenotype than MIF deficiency. We hypothesized that these observations may be explained by a second MIF-like ligand, and we considered a probable candidate to be the protein encoded by the homologous, D -dopachrome tautomerase (D-DT) gene. We show that recombinant D-DT protein binds CD74 with high affinity, leading to activation of ERK1/2 MAP kinase and downstream proinflammatory pathways. Circulating D-DT levels correlate with disease severity in sepsis or malignancy, and the specific immunoneutralization of D-DT protects mice from lethal endotoxemia by reducing the expression of downstream effector cytokines. These data indicate that D-DT is a MIF-like cytokine with an overlapping spectrum of activities that are important fo...
Autoimmunity leads to the activation of innate effector pathways, proinflammatory cytokine produc... more Autoimmunity leads to the activation of innate effector pathways, proinflammatory cytokine production, and end-organ injury. Macrophage migration inhibitory factor (MIF) is an upstream activator of the innate response that mediates the recruitment and retention of monocytes via CD74 and associated chemokine receptors, and it has a role in the maintenance of B lymphocytes. High-expression MIF alleles also are associated with end-organ damage in different autoimmune diseases. We assessed the therapeutic efficacy of (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester (ISO-1), an orally bioavailable MIF antagonist, in two distinct models of systemic lupus erythematosus: the NZB/NZW F1 and the MRL/lpr mouse strains. ISO-1, like anti-MIF, inhibited the interaction between MIF and its receptor, CD74, and in each model of disease, it reduced functional and histological indices of glomerulonephritis, CD74+ and CXCR4+ leukocyte recruitment, and proinflammatory cytokine ...
Macrophage migration inhibitory factor (MIF) is an innate cytokine whose main actions include cou... more Macrophage migration inhibitory factor (MIF) is an innate cytokine whose main actions include counter-regulating the immunosuppressive action of glucocorticoids and inhibiting activationinduced apoptosis. MIF is encoded in a functionally polymorphic locus and human genetic studies have shown significant relationships between high-expression MIF alleles, host inflammatory responses, and improved clinical outcome from infections. A recently completed candidate gene association study in the autoimmune disease systemic lupus erythematosus (SLE) indicates that individuals with a high-expression MIF allele have reduced incidence of SLE. Among patients with established disease however, those with end-organ complications have increased frequency of high-expression MIF alleles. Plasma MIF levels and Toll-like receptor (TLR) stimulated MIF production also reflect the underlying MIF genotype. These data suggest that MIF exerts a dual influence on the immunopathogenesis of SLE: high-expression MIF alleles are associated with a reduced susceptibility to SLE, perhaps by enhancing clearance of autoimmunogenic pathogens; once SLE develops however, low-expression MIF alleles protect from ensuing inflammatory endorgan damage. These data thus provide an example of the potential evolutionary advantage of maintaining an autoimmunity susceptibility gene in the population in that high-expression MIF alleles may allow for a maximal anti-infective response despite risk of autoimmunity. These results also support the clinical feasibility of pharmacologic MIF antagonism as such therapies may be most effectively applied in those individuals who, on the basis of their genotype, manifest a MIF dependent form of autoimmunity.
D-dopachrome tautomerase (D-DT) is a newly described cytokine and a member of the macrophage migr... more D-dopachrome tautomerase (D-DT) is a newly described cytokine and a member of the macrophage migration inhibitory factor (MIF) protein superfamily. MIF is a broadly expressed pro-inflammatory cytokine that regulates both the innate and the adaptive immune response. MIF activates the MAP kinase cascade, modulates cell migration, and counteracts the immunosuppressive effects of glucocorticoids. For many cell types, MIF also acts as an important survival or anti-apoptotic factor. Circulating MIF levels are elevated in the serum in different infectious and autoimmune diseases, and neutralization of the MIF protein via antibodies or small molecule antagonists improves the outcome in numerous animal models of human disease. Recently, a detailed investigation of the biological role of the closely homologous protein D-DT, which is encoded by a gene adjacent to MIF, revealed an overlapping functional spectrum with MIF. The D-DT protein also is present in most tissues and circulates in serum at similar concentrations as MIF. D-DT binds the MIF cell surface receptor complex, CD74/CD44, with high affinity and induces similar cell signaling and effector functions. Furthermore, an analysis of the signaling properties of the two proteins showed that they work cooperatively, and that neutralization of D-DT in vivo significantly decreases inflammation. In this review, we highlight the similarities and differences between MIF and D-DT, which we propose to designate "MIF-2" and discuss the implication of D-DT/MIF-2 expression in MIF-based therapies.
The cytokine macrophage migration inhibitory factor (MIF) protects the heart through AMPK activat... more The cytokine macrophage migration inhibitory factor (MIF) protects the heart through AMPK activation. Autophagy, a conserved pathway for bulk degradation of intracellular proteins and organelles, helps preserve and recycle energy and nutrients for cells to survive under starvation. This study was designed to examine the role of MIF in cardiac homeostasis and autophagy regulation following an acute starvation challenge. Methods and results Wild-type (WT) and MIF knockout mice were starved for 48 h. Echocardiographic data revealed little effect of starvation on cardiac geometry, contractile and intracellular Ca 2+ properties. MIF deficiency unmasked an increase in left ventricular end-systolic diameter, a drop in fractional shortening associated with cardiomyocyte contractile and intracellular Ca 2+ anomalies following starvation. Interestingly, the unfavourable effect of MIF deficiency was associated with interruption of starvation-induced autophagy. Furthermore, restoration of autophagy using rapamycin partially protected against starvation-induced cardiomyocyte contractile defects. In our in vitro model of starvation, neonatal mouse cardiomyocytes from WT and MIF 2/2 mice and H9C2 cells were treated with serum free-glucose free DMEM for 2 h. MIF depletion dramatically attenuated starvation-induced autophagic vacuole formation in neonatal mouse cardiomyocytes and exacerbated starvation-induced cell death in H9C2 cells. Conclusion In summary, these results indicate that MIF plays a permissive role in the maintenance of cardiac contractile function under starvation by regulation of autophagy.
Objectives-Macrophage migration inhibitory factor (MIF) facilitates multiple aspects of inflammat... more Objectives-Macrophage migration inhibitory factor (MIF) facilitates multiple aspects of inflammatory arthritis, the pathogenesis of which is significantly contributed to by neutrophils. The effects of MIF on neutrophil recruitment are unknown. We investigated the contribution of MIF to the regulation of neutrophil chemotactic responses. Methods-K/BxN serum transfer arthritis was induced in wild-type (WT), MIF-/-, and MCP1 (CCL2)-deficient mice, and in WT mice treated with anti-KC (CXCL1) mAb. In vivo leukocyte trafficking was examined using intravital microscopy, and in vitro neutrophil function was examined using migration chambers and MAP kinase activation. Results-K/BxN serum transfer arthritis was markedly attenuated in MIF-/mice, with reductions in clinical and histological severity as well as synovial expression of KC and IL-1. Arthritis was also reduced by anti-KC antibody treatment, but not in MCP-1-deficient mice. In vivo neutrophil recruitment responses to KC were reduced in MIF-/mice. Similarly, MIF-/neutrophils exhibited reduced in vitro chemotactic responses to KC, despite unaltered chemokine receptor expression. Reduced chemotactic responses in MIF-/neutrophils were associated with reduced phosphorylation of p38 and ERK MAP kinases. Conclusion-These data suggest MIF promotes neutrophil trafficking in inflammatory arthritis via facilitation of chemokine-induced migratory responses and MAP kinase activation. Therapeutic MIF inhibition could limit synovial neutrophil recruitment. Neutrophils constitute the predominant leukocyte class in the synovial fluid of patients with inflammatory arthritides such as rheumatoid arthritis (RA). Human RA synovial fluid contains numerous active neutrophil chemoattractants, including chemokines such as GROalpha (CXCL1), that are likely to have key roles in pathological neutrophil recruitment
Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine whose involvement in t... more Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine whose involvement in tumor necrosis factor ␣ (TNF␣) synthesis and T cell activation suggests a role in the pathogenesis of rheumatoid arthritis (RA). Antagonism of MIF is associated with marked inhibition of animal models of RA. Uniquely, MIF is inducible by low concentrations of glucocorticoids. We sought to investigate the expression of MIF in RA synovial tissue. Methods. MIF was demonstrated in human RA synovium by immunohistochemistry, flow cytometry, enzyme-linked immunosorbent assay (ELISA), and reverse transcription-polymerase chain reaction (RT-PCR). Regulation of MIF expression was investigated by treatment of cultured fibroblast-like synoviocytes (FLS) with interleukin-1 (IL-1), TNF␣, or interferon-␥ (IFN␥), and dexamethasone (DEX). Mononuclear cell TNF␣ release after exposure to FLS-conditioned medium was measured by ELISA. Results. MIF was present in RA synovial lining CD14؉ macrophages and FLS. Constitutive MIF messenger RNA (mRNA) expression was demonstrated by RT-PCR of RNA from unstimulated cultured RA FLS, which also released abundant MIF. Serum, synovial fluid, and FLS intracellular MIF were significantly higher in RA patients than in controls. Synoviocyte MIF was not increased by IL-1, TNF␣, or IFN␥. In contrast, DEX 10 ؊7 M significantly reduced synoviocyte MIF, while DEX 10 ؊10-10 ؊12 M induced a significant increase in MIF and MIF mRNA. Peripheral blood mononuclear cell TNF␣ release was induced by culture in RA FLSconditioned medium, and this induction was significantly abrogated by monoclonal anti-MIF antibody, suggesting that MIF is an upstream regulator of TNF␣ release. Conclusion. These data represent the first demonstration of the cytokine MIF in human autoimmune disease and suggest MIF as a potential therapeutic target in RA. Macrophage migration inhibitory factor (MIF) is increasingly recognized as an important regulator of immune and inflammatory responses. It is released by activated T lymphocytes and macrophages and upregulates the proinflammatory activity of these cells (1-4). While its original description focused on its ability to prevent the random migration of macrophages in culture, evidence of a broad range of proinflammatory actions continues to emerge. Of note, MIF induces macrophage secretion of tumor necrosis factor ␣ (TNF␣) and promotes interferon-␥ (IFN␥)-induced production of nitric oxide by mouse macrophages (5-7). Macrophage intracellular killing and phagocytic function is up-regulated in the presence of MIF (8,9). MIF has also been demonstrated to be a crucial cofactor in T cell activation (2). Recently, MIF release by immune cells has been shown to be biphasically regulated by
Arteriosclerosis, Thrombosis, and Vascular Biology, 2004
Objective— Inflammation plays an essential role in atherosclerosis and restenosis. Macrophage mig... more Objective— Inflammation plays an essential role in atherosclerosis and restenosis. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that is widely expressed in vascular cells. However, there is no in vivo evidence that MIF participates directly in vascular injury and repair. Therefore, we investigated the effect of MIF blockade on the response to experimental angioplasty in atherosclerosis-susceptible mice. Methods and Results— Carotid artery dilation (2.5 atm) and complete endothelial denudation were performed in male C57BL/6J LDL receptor-deficient mice treated with a neutralizing anti-MIF or isotype control monoclonal antibody. After 7 days and 28 days, intimal and medial sizes were measured and intima/media area ratio (I/M) was calculated. Intimal thickening and I/M were reduced significantly by anti-MIF compared with control antibody. Vascular injury was accompanied by progressive vessel enlargement or “positive remodeling” that was comparable in both ...
Macrophage migration inhibitory factor (MIF) is an upstream regulator of immune and inflammatory ... more Macrophage migration inhibitory factor (MIF) is an upstream regulator of immune and inflammatory responses; however, its role in Helicobacter pylori (HP)-associated gastritis remains unknown. We infected MIF knockout (KO) and wild-type mice with SS1 HP and found that 2 weeks after infection, MIF and its receptor CD74 were markedly up-regulated in wild-type mice. This up-regulation preceded the upregulation of both tumor necrosis factor-␣ and intercellular adhesion molecule-1, as well as the development of moderate gastritis at 8 weeks, as determined by a significant infiltration of neutrophils, T cells, and macrophages. In contrast, KO mice were protected against HP-induced gastritis by preventing the up-regulation of CD74 and Th1-mediated immune injury, including a reduction in the Th1 transcriptional factor T-bet and the expression of interferon-␥. Additionally, inhibition of skin delayed type hypersensitivity reactions to HP antigens in KO mice also suggested a critical role for MIF in cell-mediated injury. A regulatory role for MIF in Th1-immune responses was further demonstrated by the finding that antigenprimed CD4 ؉ T cells lacking MIF failed to differentiate into the Th1 phenotype; these cells were instead promoted to Th2 differentiation after challenge with HP antigen in vitro. Results from this study indicated that inhibition of HP-induced innate immune responses and Th1-mediated immune injury may be the key mechanisms by which KO mice failed to develop gastritis after HP infection.
Macrophage migration inhibitory factor (MIF) accounts for one of the first cytokine activities to... more Macrophage migration inhibitory factor (MIF) accounts for one of the first cytokine activities to have been described, and it has emerged recently to be an important regulator of innate and adaptive immunity. MIF is an upstream activator of monocytes/macrophages, and it is centrally involved in the pathogenesis of septic shock, arthritis, and other inflammatory conditions. The protein is encoded by a unique but highly conserved gene, and X-ray crystallography studies have shown MIF to define a new protein fold and structural superfamily. Although recent work has begun to illuminate the signal transduction pathways activated by MIF, the nature of its membrane receptor has not been known. Using expression cloning and functional analysis, we report herein that CD74, a Type II transmembrane protein, is a high-affinity binding protein for MIF. MIF binds to the extracellular domain of CD74, and CD74 is required for MIF-induced activation of the extracellular signal–regulated kinase–1/2 MA...
Macrophage migration inhibitory factor (MIF) is an immunoregulatory cytokine that has been extens... more Macrophage migration inhibitory factor (MIF) is an immunoregulatory cytokine that has been extensively characterized in human disease and in mouse models. Its pro-inflammatory functions in mammals includes the retention of tissue macrophages and a unique ability to counteract the immunosuppressive activity of glucocorticoids. MIF also acts as a survival factor by preventing activation-induced apoptosis and by promoting sustained expression of inflammatory factors such as TNF-α and nitric oxide. The pro-inflammatory activity of MIF has been shown to be protective against Leishmania major infection in mouse models of cutaneous disease, however the precise role of this cytokine in human infections is less clear. Moreover, various species of Leishmania produce their own MIF orthologs, and there is evidence that these may drive an inflammatory environment that is detrimental to the host response. Herein the immune response to Leishmania in mouse models and humans will be reviewed, and th...
Plasmodium species produce an ortholog of the cytokine macrophage migration inhibitory factor, PM... more Plasmodium species produce an ortholog of the cytokine macrophage migration inhibitory factor, PMIF, which modulates the host inflammatory response to malaria. Using a novel RNA replicon-based vaccine, we show the impact of PMIF immunoneutralization on the host response and observed improved control of liver and blood-stage Plasmodium infection, and complete protection from re-infection. Vaccination against PMIF delayed blood-stage patency after sporozoite infection, reduced the expression of the Th1-associated inflammatory markers TNF-α, IL-12, and IFN-γ during blood-stage infection, augmented Tfh cell and germinal center responses, increased anti-Plasmodium antibody titers, and enhanced the differentiation of antigen-experienced memory CD4 T cells and liver-resident CD8 T cells. Protection from re-infection was recapitulated by the adoptive transfer of CD8 or CD4 T cells from PMIF RNA immunized hosts. Parasite MIF inhibition may be a useful approach to promote immunity to Plasmodi...
Human genetic polymorphisms associated with decreased expression of macrophage migration inhibito... more Human genetic polymorphisms associated with decreased expression of macrophage migration inhibitory factor (MIF) have been linked to the risk of community-acquired pneumonia. Because Streptococcus pneumoniae is the leading cause of communityacquired pneumonia and nasal carriage is a precursor to invasive disease, we explored the role of MIF in the clearance of pneumococcal colonization in a mouse model. MIF-deficient mice (Mif 2/2) showed prolonged colonization with both avirulent (23F) and virulent (6A) pneumococcal serotypes compared with wild-type animals. Pneumococcal carriage led to both local upregulation of MIF expression and systemic increase of the cytokine. Delayed clearance in the Mif 2/2 mice was correlated with reduced numbers of macrophages in upper respiratory tract lavages as well as impaired upregulation of MCP-1/CCL2. We found that primary human monocyte-derived macrophages as well as THP-1 macrophages produced MIF upon pneumococcal infection in a pneumolysin-dependent manner. Pneumolysin-induced MIF production required its pore-forming activity and phosphorylation of p38-MAPK in macrophages, with sustained p38-MAPK phosphorylation abrogated in the setting of MIF deficiency. Challenge with pneumolysin-deficient bacteria demonstrated reduced MIF upregulation, decreased numbers of macrophages in the nasopharynx, and less effective clearance. Mif 2/2 mice also showed reduced Ab response to pneumococcal colonization and impaired ability to clear secondary carriage. Finally, local administration of MIF was able to restore bacterial clearance and macrophage accumulation in Mif 2/2 mice. Our work suggests that MIF is important for innate and adaptive immunity to pneumococcal colonization and could be a contributing factor in genetic differences in pneumococcal disease susceptibility.
The Journal of clinical investigation, Jan 11, 2016
The immunoregulatory cytokine macrophage migration inhibitory factor (MIF) is encoded in a functi... more The immunoregulatory cytokine macrophage migration inhibitory factor (MIF) is encoded in a functionally polymorphic locus that is linked to the susceptibility of autoimmune and infectious diseases. The MIF promoter contains a 4-nucleotide microsatellite polymorphism (-794 CATT) that repeats 5 to 8 times in the locus, with greater numbers of repeats associated with higher mRNA levels. Because there is no information about the transcriptional regulation of these common alleles, we used oligonucleotide affinity chromatography and liquid chromatography-mass spectrometry to identify nuclear proteins that interact with the -794 CATT5-8 site. An analysis of monocyte nuclear lysates revealed that the transcription factor ICBP90 (also known as UHRF1) is the major protein interacting with the MIF microsatellite. We found that ICBP90 is essential for MIF transcription from monocytes/macrophages, B and T lymphocytes, and synovial fibroblasts, and TLR-induced MIF transcription is regulated in an...
FASEB journal : official publication of the Federation of American Societies for Experimental Biology, Jan 25, 2018
Sepsis-leading to septic shock-is the leading cause of death in intensive care units. The systemi... more Sepsis-leading to septic shock-is the leading cause of death in intensive care units. The systemic inflammatory response to infection, which is initiated by activated myeloid cells, plays a key role in the lethal outcome. Macrophage migration inhibitory factor (MIF) is an upstream immunoregulatory mediator, released by myeloid cells, that underlies a common genetic susceptibility to different infections and septic shock. Accordingly, strategies that are aimed at inhibiting the action of MIF have therapeutic potential. Here, we report the isolation and characterization of tailorable, small, affinity-matured nanobodies (Nbs; single-domain antigen-binding fragments derived from camelid heavy-chain Abs) directed against MIF. Of importance, these bioengineered Nbs bind both human and mouse MIFs with nanomolar affinity. NbE5 and NbE10 inhibit key MIF functions that can exacerbate septic shock, such as the tautomerase activity of MIF (by blocking catalytic pocket residues that are critical...
Proceedings of the National Academy of Sciences, 2017
Significance The biological processes that are involved in the progression of multiple sclerosis ... more Significance The biological processes that are involved in the progression of multiple sclerosis (MS) are far from complete. Macrophage migration inhibitory factor (MIF) and its homolog, D-dopachrome tautomerase (D-DT), are immunoregulatory cytokines known to be involved in the worsening of various autoimmune disorders. We demonstrate that genetically controlled high MIF expression (and D-DT) promotes MS progression in males, suggesting that these two factors are sex-specific disease modifiers. In addition, we show that MIF or D-DT deficiency ameliorates the disease severity of the murine model of MS. Our data suggest that targeting CD74, the common receptor for MIF and D-DT, with therapies such as partial MHC class II constructs could be therapeutically beneficial for inhibiting MS clinical progression in selected patients.
Macrophage migration inhibitory factor (MIF) was first described as a cytokine 50 years ago, and ... more Macrophage migration inhibitory factor (MIF) was first described as a cytokine 50 years ago, and emerged in mammals as a pleiotropic protein with pro-inflammatory, chemotactic, and growthpromoting activities. In addition, MIF has gained substantial attention as a pivotal upstream mediator of innate and adaptive immune responses and with pathologic roles in several diseases. Of less importance in mammals is an intrinsic but non-physiologic enzymatic activity that points to MIF's evolution from an ancient defense molecule. Therefore, it is not surprising that mif-like genes also have been found across a range of different organisms including bacteria, plants, protozoa, helminths, molluscs, arthropods, fish, amphibians and birds. While Genebank analysis identifying mif-like genes across species is extensive, contained herein is an overview of the nonmammalian MIF-like proteins that have been most well studied experimentally. For many of these organisms, MIF contributes to an innate defense system or plays a role in development. For parasitic organisms however, MIF appears to function as a virulence factor aiding in the establishment or persistence of infection by modulating the host immune response. Consequently, a combined targeting of both parasitic and host MIF could lead to more effective treatment strategies for parasitic diseases of socioeconomic importance.
Chronic helminth infections are associated with modulation of host cellular immune responses, pre... more Chronic helminth infections are associated with modulation of host cellular immune responses, presumably to prolong parasite survival within the mammalian host. This phenomenon is attributed, at least in part, to the elaboration of parasite molecules, including orthologs of host cytokines and receptors, at the host-parasite interface. This review describes recent progress in the characterization of macrophage migration inhibitory factor (MIF) orthologs from parasitic nematodes. The roles of these molecules in parasite developmental biology and pathogenesis are discussed. Further knowledge of the species-specific activities and three-dimensional structures of human and parasitic nematode MIF molecules should make them ideal targets for drug-and/or vaccine-based strategies aimed at nematode disease control. Helminth immunomodulation At the host-parasite interface parasitic nematodes produce a panoply of molecules, both on the cuticular surface and/or released in excretory-secretory (ES) products, which mediate their ability to survive for long periods of time despite the actions of the host immune system [1]. These parasite mediators drive potentially immune-evasive processes that allow for the parasites' prolonged survival within their hosts [2]. There is functional diversity in these parasite-derived immune modulators that presumably reflects a long-standing coevolutionary relationship between nematode parasites and their respective hosts. Putative nematode virulence factors that might subvert host immune responses effectively include proteases, protease inhibitors, antioxidant proteins and orthologs of mammalian cytokines and their receptors [3]. Studies by several investigators have provided evidence of the elaboration by parasitic nematodes of macrophage migration inhibitory factor (MIF) orthologs, which modulate the taxis of immune cells, altering their gene expression and the subsequent production of cytokines.
Proceedings of the National Academy of Sciences, 2011
Macrophage migration inhibitory factor (MIF) is a pivotal regulator of the immune response. Neutr... more Macrophage migration inhibitory factor (MIF) is a pivotal regulator of the immune response. Neutralization or genetic deletion of MIF does not completely abrogate activation responses, however, and deletion of the MIF receptor, CD74, produces a more pronounced phenotype than MIF deficiency. We hypothesized that these observations may be explained by a second MIF-like ligand, and we considered a probable candidate to be the protein encoded by the homologous, D -dopachrome tautomerase (D-DT) gene. We show that recombinant D-DT protein binds CD74 with high affinity, leading to activation of ERK1/2 MAP kinase and downstream proinflammatory pathways. Circulating D-DT levels correlate with disease severity in sepsis or malignancy, and the specific immunoneutralization of D-DT protects mice from lethal endotoxemia by reducing the expression of downstream effector cytokines. These data indicate that D-DT is a MIF-like cytokine with an overlapping spectrum of activities that are important fo...
Autoimmunity leads to the activation of innate effector pathways, proinflammatory cytokine produc... more Autoimmunity leads to the activation of innate effector pathways, proinflammatory cytokine production, and end-organ injury. Macrophage migration inhibitory factor (MIF) is an upstream activator of the innate response that mediates the recruitment and retention of monocytes via CD74 and associated chemokine receptors, and it has a role in the maintenance of B lymphocytes. High-expression MIF alleles also are associated with end-organ damage in different autoimmune diseases. We assessed the therapeutic efficacy of (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester (ISO-1), an orally bioavailable MIF antagonist, in two distinct models of systemic lupus erythematosus: the NZB/NZW F1 and the MRL/lpr mouse strains. ISO-1, like anti-MIF, inhibited the interaction between MIF and its receptor, CD74, and in each model of disease, it reduced functional and histological indices of glomerulonephritis, CD74+ and CXCR4+ leukocyte recruitment, and proinflammatory cytokine ...
Macrophage migration inhibitory factor (MIF) is an innate cytokine whose main actions include cou... more Macrophage migration inhibitory factor (MIF) is an innate cytokine whose main actions include counter-regulating the immunosuppressive action of glucocorticoids and inhibiting activationinduced apoptosis. MIF is encoded in a functionally polymorphic locus and human genetic studies have shown significant relationships between high-expression MIF alleles, host inflammatory responses, and improved clinical outcome from infections. A recently completed candidate gene association study in the autoimmune disease systemic lupus erythematosus (SLE) indicates that individuals with a high-expression MIF allele have reduced incidence of SLE. Among patients with established disease however, those with end-organ complications have increased frequency of high-expression MIF alleles. Plasma MIF levels and Toll-like receptor (TLR) stimulated MIF production also reflect the underlying MIF genotype. These data suggest that MIF exerts a dual influence on the immunopathogenesis of SLE: high-expression MIF alleles are associated with a reduced susceptibility to SLE, perhaps by enhancing clearance of autoimmunogenic pathogens; once SLE develops however, low-expression MIF alleles protect from ensuing inflammatory endorgan damage. These data thus provide an example of the potential evolutionary advantage of maintaining an autoimmunity susceptibility gene in the population in that high-expression MIF alleles may allow for a maximal anti-infective response despite risk of autoimmunity. These results also support the clinical feasibility of pharmacologic MIF antagonism as such therapies may be most effectively applied in those individuals who, on the basis of their genotype, manifest a MIF dependent form of autoimmunity.
D-dopachrome tautomerase (D-DT) is a newly described cytokine and a member of the macrophage migr... more D-dopachrome tautomerase (D-DT) is a newly described cytokine and a member of the macrophage migration inhibitory factor (MIF) protein superfamily. MIF is a broadly expressed pro-inflammatory cytokine that regulates both the innate and the adaptive immune response. MIF activates the MAP kinase cascade, modulates cell migration, and counteracts the immunosuppressive effects of glucocorticoids. For many cell types, MIF also acts as an important survival or anti-apoptotic factor. Circulating MIF levels are elevated in the serum in different infectious and autoimmune diseases, and neutralization of the MIF protein via antibodies or small molecule antagonists improves the outcome in numerous animal models of human disease. Recently, a detailed investigation of the biological role of the closely homologous protein D-DT, which is encoded by a gene adjacent to MIF, revealed an overlapping functional spectrum with MIF. The D-DT protein also is present in most tissues and circulates in serum at similar concentrations as MIF. D-DT binds the MIF cell surface receptor complex, CD74/CD44, with high affinity and induces similar cell signaling and effector functions. Furthermore, an analysis of the signaling properties of the two proteins showed that they work cooperatively, and that neutralization of D-DT in vivo significantly decreases inflammation. In this review, we highlight the similarities and differences between MIF and D-DT, which we propose to designate "MIF-2" and discuss the implication of D-DT/MIF-2 expression in MIF-based therapies.
The cytokine macrophage migration inhibitory factor (MIF) protects the heart through AMPK activat... more The cytokine macrophage migration inhibitory factor (MIF) protects the heart through AMPK activation. Autophagy, a conserved pathway for bulk degradation of intracellular proteins and organelles, helps preserve and recycle energy and nutrients for cells to survive under starvation. This study was designed to examine the role of MIF in cardiac homeostasis and autophagy regulation following an acute starvation challenge. Methods and results Wild-type (WT) and MIF knockout mice were starved for 48 h. Echocardiographic data revealed little effect of starvation on cardiac geometry, contractile and intracellular Ca 2+ properties. MIF deficiency unmasked an increase in left ventricular end-systolic diameter, a drop in fractional shortening associated with cardiomyocyte contractile and intracellular Ca 2+ anomalies following starvation. Interestingly, the unfavourable effect of MIF deficiency was associated with interruption of starvation-induced autophagy. Furthermore, restoration of autophagy using rapamycin partially protected against starvation-induced cardiomyocyte contractile defects. In our in vitro model of starvation, neonatal mouse cardiomyocytes from WT and MIF 2/2 mice and H9C2 cells were treated with serum free-glucose free DMEM for 2 h. MIF depletion dramatically attenuated starvation-induced autophagic vacuole formation in neonatal mouse cardiomyocytes and exacerbated starvation-induced cell death in H9C2 cells. Conclusion In summary, these results indicate that MIF plays a permissive role in the maintenance of cardiac contractile function under starvation by regulation of autophagy.
Objectives-Macrophage migration inhibitory factor (MIF) facilitates multiple aspects of inflammat... more Objectives-Macrophage migration inhibitory factor (MIF) facilitates multiple aspects of inflammatory arthritis, the pathogenesis of which is significantly contributed to by neutrophils. The effects of MIF on neutrophil recruitment are unknown. We investigated the contribution of MIF to the regulation of neutrophil chemotactic responses. Methods-K/BxN serum transfer arthritis was induced in wild-type (WT), MIF-/-, and MCP1 (CCL2)-deficient mice, and in WT mice treated with anti-KC (CXCL1) mAb. In vivo leukocyte trafficking was examined using intravital microscopy, and in vitro neutrophil function was examined using migration chambers and MAP kinase activation. Results-K/BxN serum transfer arthritis was markedly attenuated in MIF-/mice, with reductions in clinical and histological severity as well as synovial expression of KC and IL-1. Arthritis was also reduced by anti-KC antibody treatment, but not in MCP-1-deficient mice. In vivo neutrophil recruitment responses to KC were reduced in MIF-/mice. Similarly, MIF-/neutrophils exhibited reduced in vitro chemotactic responses to KC, despite unaltered chemokine receptor expression. Reduced chemotactic responses in MIF-/neutrophils were associated with reduced phosphorylation of p38 and ERK MAP kinases. Conclusion-These data suggest MIF promotes neutrophil trafficking in inflammatory arthritis via facilitation of chemokine-induced migratory responses and MAP kinase activation. Therapeutic MIF inhibition could limit synovial neutrophil recruitment. Neutrophils constitute the predominant leukocyte class in the synovial fluid of patients with inflammatory arthritides such as rheumatoid arthritis (RA). Human RA synovial fluid contains numerous active neutrophil chemoattractants, including chemokines such as GROalpha (CXCL1), that are likely to have key roles in pathological neutrophil recruitment
Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine whose involvement in t... more Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine whose involvement in tumor necrosis factor ␣ (TNF␣) synthesis and T cell activation suggests a role in the pathogenesis of rheumatoid arthritis (RA). Antagonism of MIF is associated with marked inhibition of animal models of RA. Uniquely, MIF is inducible by low concentrations of glucocorticoids. We sought to investigate the expression of MIF in RA synovial tissue. Methods. MIF was demonstrated in human RA synovium by immunohistochemistry, flow cytometry, enzyme-linked immunosorbent assay (ELISA), and reverse transcription-polymerase chain reaction (RT-PCR). Regulation of MIF expression was investigated by treatment of cultured fibroblast-like synoviocytes (FLS) with interleukin-1 (IL-1), TNF␣, or interferon-␥ (IFN␥), and dexamethasone (DEX). Mononuclear cell TNF␣ release after exposure to FLS-conditioned medium was measured by ELISA. Results. MIF was present in RA synovial lining CD14؉ macrophages and FLS. Constitutive MIF messenger RNA (mRNA) expression was demonstrated by RT-PCR of RNA from unstimulated cultured RA FLS, which also released abundant MIF. Serum, synovial fluid, and FLS intracellular MIF were significantly higher in RA patients than in controls. Synoviocyte MIF was not increased by IL-1, TNF␣, or IFN␥. In contrast, DEX 10 ؊7 M significantly reduced synoviocyte MIF, while DEX 10 ؊10-10 ؊12 M induced a significant increase in MIF and MIF mRNA. Peripheral blood mononuclear cell TNF␣ release was induced by culture in RA FLSconditioned medium, and this induction was significantly abrogated by monoclonal anti-MIF antibody, suggesting that MIF is an upstream regulator of TNF␣ release. Conclusion. These data represent the first demonstration of the cytokine MIF in human autoimmune disease and suggest MIF as a potential therapeutic target in RA. Macrophage migration inhibitory factor (MIF) is increasingly recognized as an important regulator of immune and inflammatory responses. It is released by activated T lymphocytes and macrophages and upregulates the proinflammatory activity of these cells (1-4). While its original description focused on its ability to prevent the random migration of macrophages in culture, evidence of a broad range of proinflammatory actions continues to emerge. Of note, MIF induces macrophage secretion of tumor necrosis factor ␣ (TNF␣) and promotes interferon-␥ (IFN␥)-induced production of nitric oxide by mouse macrophages (5-7). Macrophage intracellular killing and phagocytic function is up-regulated in the presence of MIF (8,9). MIF has also been demonstrated to be a crucial cofactor in T cell activation (2). Recently, MIF release by immune cells has been shown to be biphasically regulated by
Arteriosclerosis, Thrombosis, and Vascular Biology, 2004
Objective— Inflammation plays an essential role in atherosclerosis and restenosis. Macrophage mig... more Objective— Inflammation plays an essential role in atherosclerosis and restenosis. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that is widely expressed in vascular cells. However, there is no in vivo evidence that MIF participates directly in vascular injury and repair. Therefore, we investigated the effect of MIF blockade on the response to experimental angioplasty in atherosclerosis-susceptible mice. Methods and Results— Carotid artery dilation (2.5 atm) and complete endothelial denudation were performed in male C57BL/6J LDL receptor-deficient mice treated with a neutralizing anti-MIF or isotype control monoclonal antibody. After 7 days and 28 days, intimal and medial sizes were measured and intima/media area ratio (I/M) was calculated. Intimal thickening and I/M were reduced significantly by anti-MIF compared with control antibody. Vascular injury was accompanied by progressive vessel enlargement or “positive remodeling” that was comparable in both ...
Macrophage migration inhibitory factor (MIF) is an upstream regulator of immune and inflammatory ... more Macrophage migration inhibitory factor (MIF) is an upstream regulator of immune and inflammatory responses; however, its role in Helicobacter pylori (HP)-associated gastritis remains unknown. We infected MIF knockout (KO) and wild-type mice with SS1 HP and found that 2 weeks after infection, MIF and its receptor CD74 were markedly up-regulated in wild-type mice. This up-regulation preceded the upregulation of both tumor necrosis factor-␣ and intercellular adhesion molecule-1, as well as the development of moderate gastritis at 8 weeks, as determined by a significant infiltration of neutrophils, T cells, and macrophages. In contrast, KO mice were protected against HP-induced gastritis by preventing the up-regulation of CD74 and Th1-mediated immune injury, including a reduction in the Th1 transcriptional factor T-bet and the expression of interferon-␥. Additionally, inhibition of skin delayed type hypersensitivity reactions to HP antigens in KO mice also suggested a critical role for MIF in cell-mediated injury. A regulatory role for MIF in Th1-immune responses was further demonstrated by the finding that antigenprimed CD4 ؉ T cells lacking MIF failed to differentiate into the Th1 phenotype; these cells were instead promoted to Th2 differentiation after challenge with HP antigen in vitro. Results from this study indicated that inhibition of HP-induced innate immune responses and Th1-mediated immune injury may be the key mechanisms by which KO mice failed to develop gastritis after HP infection.
Macrophage migration inhibitory factor (MIF) accounts for one of the first cytokine activities to... more Macrophage migration inhibitory factor (MIF) accounts for one of the first cytokine activities to have been described, and it has emerged recently to be an important regulator of innate and adaptive immunity. MIF is an upstream activator of monocytes/macrophages, and it is centrally involved in the pathogenesis of septic shock, arthritis, and other inflammatory conditions. The protein is encoded by a unique but highly conserved gene, and X-ray crystallography studies have shown MIF to define a new protein fold and structural superfamily. Although recent work has begun to illuminate the signal transduction pathways activated by MIF, the nature of its membrane receptor has not been known. Using expression cloning and functional analysis, we report herein that CD74, a Type II transmembrane protein, is a high-affinity binding protein for MIF. MIF binds to the extracellular domain of CD74, and CD74 is required for MIF-induced activation of the extracellular signal–regulated kinase–1/2 MA...
Macrophage migration inhibitory factor (MIF) is an immunoregulatory cytokine that has been extens... more Macrophage migration inhibitory factor (MIF) is an immunoregulatory cytokine that has been extensively characterized in human disease and in mouse models. Its pro-inflammatory functions in mammals includes the retention of tissue macrophages and a unique ability to counteract the immunosuppressive activity of glucocorticoids. MIF also acts as a survival factor by preventing activation-induced apoptosis and by promoting sustained expression of inflammatory factors such as TNF-α and nitric oxide. The pro-inflammatory activity of MIF has been shown to be protective against Leishmania major infection in mouse models of cutaneous disease, however the precise role of this cytokine in human infections is less clear. Moreover, various species of Leishmania produce their own MIF orthologs, and there is evidence that these may drive an inflammatory environment that is detrimental to the host response. Herein the immune response to Leishmania in mouse models and humans will be reviewed, and th...
Plasmodium species produce an ortholog of the cytokine macrophage migration inhibitory factor, PM... more Plasmodium species produce an ortholog of the cytokine macrophage migration inhibitory factor, PMIF, which modulates the host inflammatory response to malaria. Using a novel RNA replicon-based vaccine, we show the impact of PMIF immunoneutralization on the host response and observed improved control of liver and blood-stage Plasmodium infection, and complete protection from re-infection. Vaccination against PMIF delayed blood-stage patency after sporozoite infection, reduced the expression of the Th1-associated inflammatory markers TNF-α, IL-12, and IFN-γ during blood-stage infection, augmented Tfh cell and germinal center responses, increased anti-Plasmodium antibody titers, and enhanced the differentiation of antigen-experienced memory CD4 T cells and liver-resident CD8 T cells. Protection from re-infection was recapitulated by the adoptive transfer of CD8 or CD4 T cells from PMIF RNA immunized hosts. Parasite MIF inhibition may be a useful approach to promote immunity to Plasmodi...
Human genetic polymorphisms associated with decreased expression of macrophage migration inhibito... more Human genetic polymorphisms associated with decreased expression of macrophage migration inhibitory factor (MIF) have been linked to the risk of community-acquired pneumonia. Because Streptococcus pneumoniae is the leading cause of communityacquired pneumonia and nasal carriage is a precursor to invasive disease, we explored the role of MIF in the clearance of pneumococcal colonization in a mouse model. MIF-deficient mice (Mif 2/2) showed prolonged colonization with both avirulent (23F) and virulent (6A) pneumococcal serotypes compared with wild-type animals. Pneumococcal carriage led to both local upregulation of MIF expression and systemic increase of the cytokine. Delayed clearance in the Mif 2/2 mice was correlated with reduced numbers of macrophages in upper respiratory tract lavages as well as impaired upregulation of MCP-1/CCL2. We found that primary human monocyte-derived macrophages as well as THP-1 macrophages produced MIF upon pneumococcal infection in a pneumolysin-dependent manner. Pneumolysin-induced MIF production required its pore-forming activity and phosphorylation of p38-MAPK in macrophages, with sustained p38-MAPK phosphorylation abrogated in the setting of MIF deficiency. Challenge with pneumolysin-deficient bacteria demonstrated reduced MIF upregulation, decreased numbers of macrophages in the nasopharynx, and less effective clearance. Mif 2/2 mice also showed reduced Ab response to pneumococcal colonization and impaired ability to clear secondary carriage. Finally, local administration of MIF was able to restore bacterial clearance and macrophage accumulation in Mif 2/2 mice. Our work suggests that MIF is important for innate and adaptive immunity to pneumococcal colonization and could be a contributing factor in genetic differences in pneumococcal disease susceptibility.
The Journal of clinical investigation, Jan 11, 2016
The immunoregulatory cytokine macrophage migration inhibitory factor (MIF) is encoded in a functi... more The immunoregulatory cytokine macrophage migration inhibitory factor (MIF) is encoded in a functionally polymorphic locus that is linked to the susceptibility of autoimmune and infectious diseases. The MIF promoter contains a 4-nucleotide microsatellite polymorphism (-794 CATT) that repeats 5 to 8 times in the locus, with greater numbers of repeats associated with higher mRNA levels. Because there is no information about the transcriptional regulation of these common alleles, we used oligonucleotide affinity chromatography and liquid chromatography-mass spectrometry to identify nuclear proteins that interact with the -794 CATT5-8 site. An analysis of monocyte nuclear lysates revealed that the transcription factor ICBP90 (also known as UHRF1) is the major protein interacting with the MIF microsatellite. We found that ICBP90 is essential for MIF transcription from monocytes/macrophages, B and T lymphocytes, and synovial fibroblasts, and TLR-induced MIF transcription is regulated in an...
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Papers by Richard Bucala