Javma-journal of The American Veterinary Medical Association, Nov 14, 1991
Feline sera were submitted to the Cornell Feline Health Center (n = 497) or to the New York State... more Feline sera were submitted to the Cornell Feline Health Center (n = 497) or to the New York State Diagnostic Laboratory (n = 1,565) for feline immunodeficiency virus (FIV) testing. Some sera (n = 166) were submitted for confirmation of previous FIV-positive results; 151 of these sera had been tested at the referring veterinary practice or laboratory, using an in-house ELISA. Excluding the samples submitted for confirmation, a total of 173 samples (9.1%) were FIV-positive; 11.6% of the clinically ill or high-risk cats and 0.49% of the healthy, low risk cats were positive for FIV antibody. A commercially available ELISA for detection of antibody to FIV was evaluated in relation to the immunofluorescent antibody (IFA) test and the immunoblot assay. The ELISA was interpreted according to the manufacturer's instructions, with the ratio of sample optical density to positive control optical density (S/P) determining a positive or negative result. The ELISA results based on the S/P interpretation were compared with a kinetics-based (KELA) interpretation of the ELISA. The KELA values were reported as positive, negative, or equivocal. Using the immunoblot as the standard, ELISA (S/P interpretation) had sensitivity of 0.93 and specificity of 0.98, whereas the IFA test had sensitivity of 0.95 and specificity of 0.98. However, the sensitivity and specificity of the ELISA (S/P interpretation) were markedly reduced for sample results falling in the KELA equivocal range, indicating that equivocal results were valid interpretations for some sera. A high number (22.5%) of the samples submitted for confirmation of a positive result from use of the in-house ELISA were determined to be negative for FIV antibody.(ABSTRACT TRUNCATED AT 250 WORDS)
Drug abuse is a common method of human immunodeficiency virus type 1 transmission, but the role o... more Drug abuse is a common method of human immunodeficiency virus type 1 transmission, but the role of opiates on lentivirus disease progression is not well understood. The feline immunodeficiency virus (FIV)/cat system was used to model the weekend opiate abuser: the nondependent, nonaddicted, and nontolerant person. Sixteen cats were placed into 4 groups: FIV only, morphine only, morphine/FIV, and controls. Multiple acute morphine exposure did not increase the severity of early lentivirus infection. On the contrary, it delayed or moderated the FIV-induced disease progression. Although the animals were exposed to only 1 injection of morphine per day for 2 consecutive days per week, the morphine-treated FIV-infected animals had a delayed onset of the FIV-induced lymphadenopathy, did not develop or had a significant delay in the FIV-induced effects on brain stem auditory evoked potentials, and demonstrated a trend toward decreased virus load.
Drug abuse is an important route of exposure to human immunodeficiency virus-1 (HIV-1). However, ... more Drug abuse is an important route of exposure to human immunodeficiency virus-1 (HIV-1). However, the role that drugs of abuse play in lentivirus disease progression remains unclear. There is a pressing need for appropriate animal models to examine the role of drugs of abuse on lentivirus disease progression. The feline immunodeficiency virus (FIV)/cat model is a legitimate system for the
Feline immunodeficiency virus (FIV), a lentivirus, causes progressive immunosuppression and neuro... more Feline immunodeficiency virus (FIV), a lentivirus, causes progressive immunosuppression and neurologic dysfunction in cats. Glucocorticoids are common therapeutic agents that are also immunosuppressive, and their use might enhance the pathogenic effects of lentivirus infections. Methylprednisolone acetate, a long-acting glucocorticoid, was administered to cats before FIV inoculation, and the course of early infection was monitored. The humoral immune response to FIV was not affected by corticosteroid treatment, but CD8 + cell-mediated antiviral activity was poor in cultures from FIV-infected cats treated with methylprednisolone. Steroidtreated cats had higher plasma viral RNA levels than untreated cats during acute viremia. In contrast, FIV-associated changes in brain stem auditory-evoked potentials were slow to develop in the methylprednisolone-treated cats. Methylprednisolone treatment of cats with established FIV infections appeared to reverse these neurophysiologic changes. These results emphasize the complexity of host-lentivirus interactions and suggest potential advantages and drawbacks of using glucocorticoids in lentivirus infections. Feline immunodeficiency virus (FIV), a lentivirus of cats that causes a disease similar to human AIDS [1], has been developed as a naturally occurring small animal model for human immunodeficiency virus (HIV) infection and disease [2-5]. Cats infected with FIV progress from acute to asymptomatic infection, followed by increasing immune system dysfunction and finally AIDS. As with HIV infection, the course of disease development is prolonged, taking several years in most cats to reach the AIDS stage. During that time, CD4 ϩ cells decline, cytokine profiles change, and macrophage functions are disrupted [5-8]. The virus also perturbs neurologic function, with changes in sleep patterns, brain stem auditory-evoked potentials (BAEPs), and spinal cord-evoked potentials occurring early in the acute and asymptomatic phases of infection [4, 9-11]. Glucocorticoid response elements are present in the promoters of several mammalian retroviruses, including 3 potential regions in the HIV-1 long terminal repeat (LTR) [12]. Another
Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direc... more Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direct effects of opiates on HIV infection are difficult to determine epidemiologically, animal models of lentivirus infection are relied upon to study the effects of opiates in the absence of confounding factors. Morphine, the predominant metabolite of heroin, is used in most experimental systems examining heroin abuse. In this study, morphine treatment of feline immunodeficiency virus (FIV)-infected cats modeled a typical pattern of escalating drug use interspersed with withdrawals. Plasma cortisol levels were measured for evidence of stress associated with morphine withdrawal. In the morphine-treated cats, cortisol levels peaked at time points corresponding to morphine withdrawal and returned to baseline levels during treatment and several weeks after the final withdrawal. Morphine-treated cats displayed clear behavioral and physical signs of opiate exposure and evidence of withdrawal when the drug was stopped. Morphine-exposed cats did not experience enhanced severity of FIV-related disease; in fact, morphine demonstrated a protective effect on FIV-associated changes in brainstem auditory evoked potentials. Our research suggests that opiate exposure is unlikely to adversely affect the progression of acute lentivirus infection and might be beneficial in controlling associated neurological disease.
Use of methamphetamine is increasingly a significant factor for the spread of human immunodeficie... more Use of methamphetamine is increasingly a significant factor for the spread of human immunodeficiency virus type 1, for in certain populations, there is a convergence of methamphetamine abuse with human immunodeficiency virus type 1 infection. Methamphetamine and human immunodeficiency virus type 1 are both individually neuropathogenic, and the neuropathology caused by these two agents occurs in overlapping brain regions. However, the biological interaction of methamphetamine with lentiviruses remains unknown. Here, we investigate the effects of simultaneous exposure of these two agents on disease progression using the feline immunodeficiency virus model. The study models the bingeing methamphetamine user with sequential and repeatedepisodes of use, which were interrupted by periods of abstinence. Methamphetamine exposure significantly accelerated and enhanced the severity of the feline immunodeficiency virus model-induced central nervous system functional pathology, as measured in delays in brainstem auditory evoked potentials. Reciprocally, feline immunodeficiency virus enhanced the severity of the methamphetamine-induced effects on brain monoamine neurotransmitter and dopamine transporter levels. The results of this study indicate that a dual potentiation occurred. That is, methamphetamine enhanced feline immunodeficiency virus model-induced central nervous system disease and feline immunodeficiency virus model enhanced the toxic effects of methamphetamine, heralding a significant concern for those individuals that are exposed to both agents.
Journal of the American Veterinary Medical Association, Jan 15, 1993
The course of naturally acquired infection with feline immunodeficiency virus was monitored in a ... more The course of naturally acquired infection with feline immunodeficiency virus was monitored in a cat over an 18-month period after diagnosis. The cat was admitted with diarrhea, poor body condition, a bite wound abscess, gingivitis, chronic fever, and splenomegaly. The cat's condition improved after splenectomy and remained stable for approximately 15 months, then began to deteriorate, as gingivitis, polyuria, polydipsia, pyrexia, multiple cutaneous masses, and hind limb paresis developed. The in vitro response of the cat's lymphocytes to mitogens was suppressed, and absolute lymphocyte counts were low. Spinal lymphosarcoma, disseminated mastocytoma, and presumptive diabetes mellitus were diagnosed after euthanasia. Decreased immune surveillance associated with feline immunodeficiency virus-related immunosuppression possibly played a role in the development of neoplastic disease in this cat.
Lymphocytes from normal cats or cats experimentally infected with feline immunodeficiency virus (... more Lymphocytes from normal cats or cats experimentally infected with feline immunodeficiency virus (FIV) were stimulated with phytohemagglutinin, pokeweed mitogen, or concanavalin A. Lymphocytes from infected cats had lower responses than those from uninfected cats. These results support the hypothesis that FIV induces immunosuppression.
A total of 878 samples from the New York State Diagnostic Laboratory (NYSDL), dating from January... more A total of 878 samples from the New York State Diagnostic Laboratory (NYSDL), dating from January 1984 to May 1987, were examined to detect antibodies to feline immunodeficiency virus (FIV). We used 2 screening methods; an indirect immunofluorescence assay (IFA) and an enzyme-linked immunosorbent assay (ELISA). Of these, 211 samples were from cats that tested negative for feline leukemia virus (FeLV) and exhibited disease signs consistent with immunodeficiency disease; 19 (9.0%) serum samples were determined to be positive. An additional 508 samples were from cats that tested FeLV-negative and were asymptomatic; 6 (1.2%) sera were determined to be positive. The final 159 samples were from FeLV-positive cats and included symptomatic and asymptomatic animals; this population of cats produced 6 (3.8%) positives. Additionally, 521 samples from the Cornell Feline Health Center (CFHC) serum bank, dating back to 1966, were tested to determine the earliest sample in which FIV antibodies cou...
Despite its fundamental importance, the educational mission of most schools of veterinary medicin... more Despite its fundamental importance, the educational mission of most schools of veterinary medicine receives far less recognition and support than the missions of research and discovery. This disparity is evident in promotion and tenure processes. Despite the frequent assertion that education is every college’s core mission, there is a broad consensus that faculty are promoted primarily on the basis of meeting expectations relative to publications and grant funding. This expectation is evident in the promotion packets faculty are expected to produce and the criteria by which those packets are reviewed. Among the outcomes is increasing difficulty in hiring and retaining faculty, including young clinicians and basic scientists who are drawn to academic institutions because of the opportunity to teach. The Regional Teaching Academy (RTA) of the West Region Consortium of Colleges of Veterinary Medicine initiated an inter-institutional collaboration to address the most important obstacles...
Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direc... more Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direct effects of opiates on HIV infection are difficult to determine epidemiologically, animal models of lentivirus infection are relied upon to study the effects of opiates in the absence of confounding factors. Morphine, the predominant metabolite of heroin, is used in most experimental systems examining heroin abuse. In this study, morphine treatment of feline immunodeficiency virus (FIV)-infected cats modeled a typical pattern of escalating drug use interspersed with withdrawals. Plasma cortisol levels were measured for evidence of stress associated with morphine withdrawal. In the morphine-treated cats, cortisol levels peaked at time points corresponding to morphine withdrawal and returned to baseline levels during treatment and several weeks after the final withdrawal. Morphine-treated cats displayed clear behavioral and physical signs of opiate exposure and evidence of withdrawal when the drug was stopped. Morphine-exposed cats did not experience enhanced severity of FIV-related disease; in fact, morphine demonstrated a protective effect on FIV-associated changes in brainstem auditory evoked potentials. Our research suggests that opiate exposure is unlikely to adversely affect the progression of acute lentivirus infection and might be beneficial in controlling associated neurological disease.
How are cats infected with FPV? FPV can survive in the environment for up to a year and a special... more How are cats infected with FPV? FPV can survive in the environment for up to a year and a specialised disinfectant is required to kill it. Most cats contract FPV from a contaminated environment via infected faeces rather than from direct contact with infected cats.
A feline immunodeficiency virus-like virus (FIV-Oma) isolated from a Pallas' cat (Otocolobus manu... more A feline immunodeficiency virus-like virus (FIV-Oma) isolated from a Pallas' cat (Otocolobus manul) is highly cytopathic in CrFK cells, in contrast to the chronic, noncytolytic infection established by an FIV isolate from a domestic cat (FIV-Fca). The virions have typical lentivirus morphology, density, and magnesium-dependent reverse transcriptase activity. The major core protein is antigenically cross-reactive with that of FIV-Fca; however, FIV-Oma transcripts do not cross-hybridize with FIV-Fca. A conserved region of the FIV-Oma pol gene has 76 to 80% nucleic acid identity with the corresponding pol regions of other feline lentiviruses and 64 to 69% identity with those of human, ovine, and equine lentiviruses.
Background: Papillomaviruses (PVs) are a group of small, non-encapsulated, species-specific DNA v... more Background: Papillomaviruses (PVs) are a group of small, non-encapsulated, species-specific DNA viruses that have been detected in a variety of mammalian and avian species including humans, canines and felines. PVs cause lesions in the skin and mucous membranes of the host and after persistent infection, a subset of PVs can cause tumors such as cervical malignancies and head and neck squamous cell carcinoma in humans. PVs from several species have been isolated and their genomes have been sequenced, thereby increasing our understanding of the mechanism of viral oncogenesis and allowing for the development of molecular assays for the detection of PV infection. In humans, molecular testing for PV DNA is used to identify patients with persistent infections at risk for developing cervical cancer. In felids, PVs have been isolated and sequenced from oral papillomatous lesions of several wild species including bobcats, Asian lions and snow leopards. Since a number of wild felids are endan...
The nucleotide sequence and genomic organization have been determined for a highly cytopathic fel... more The nucleotide sequence and genomic organization have been determined for a highly cytopathic feline immunodeficiency virus (FIV) isolated from a Pallas ’ cat. The 9747-bp provirus of this virus, FIV-Oma, has typical lentivirus organization with LTRs, gag, pol, and env open reading frames (ORFs), putative vif and rev ORFs, and an ORF similar to ORF2/ORFA of domestic cat FIV isolates. Although the FIV-Oma provirus is 300 to 600 bp longer than other FIV proviruses, these additional bases are distributed throughout the genome. Phylogenetic analysis of a conserved region of the pol gene suggests that FIV-Oma is more closely related to some of the puma and lion lentiviruses than it is to domestic cat FIV isolates; however, many regions of the genome exhibit extensive nucleotide sequence divergence. None of the eight molecular proviral clones isolated from a genomic library are infectious, but we have constructed an infectious, cytopathic clone of FIV-Oma from subcloned and PCR-amplified ...
C on d en sed from "Feline Viral D iseases," T extbook o f V eterinary Internal M ed icin e, 4th ... more C on d en sed from "Feline Viral D iseases," T extbook o f V eterinary Internal M ed icin e, 4th E dition, 1994 Feline leukem ia virus (FeLV) and felin e im m u n o d eficien cy viru s (FIV) are retroviruses w h ich infect dom estic cats and produce disease, u su ally fo llo w in g an asym ptom atic period of m onths to years. The retrovirus fam ily (the Retroviridae) uses reverse transcriptase, an R N A-depend en t D N A p olym erase' (po I), to produce a d ou b le-stran d ed D N A copy o f the virion R N A. T he nam e retrovirus is d eriv ed from this "backwards" flo w of inform ation from R N A to D N A. The D N A copy, called a provirus, integrates into the host cell chrom asom es and thus can replicate along w ith the infected host cell. R etroviru ses are d iv id e d in to three su b fa m ilie s, the Spumuvirinae, the Oncornavirinae, and the Lentivirinae, based on shared p h ysical and b ioch em ical prop erties. Cats are su scep tib le to in fe c tio n by v ir u se s from ea ch o f th ese subfam ilies. Feline syn cytiu m-fo rm in g viru s (FeSFV), a sp u m a v iru s or "foamy virus," has b e e n iso la te d from both h ea lth y and d ise a se d cats. In so m e cat pop u lation s, the in fection rate in older cats m ay be 70% or greater. In general, FeSFV is considered to have little or no p athogenicity in dom estic cats. C hronic progressive polyarthritis has been linked w ith FeSFV infection but the d isea se has not been reproduced by experim ental FeSFV infection. M any o n c o g e n ic a n im a l retro v ir u se s, in c lu d in g FeLV, b e lo n g to th e oncovirus subfam ily. Three types of feline oncoviruses have been described: (1) the en d ogen ou s oncoviruses, such as RD114, w hich are present in all felin e cells but do not replicate or cause disease; (2) the exogen ou s, replication-com petent oncovirus, FeLV; and (3) the exogen ou s, rep lication-d efective on coviruses, in c lu d in g felin e sarcom a virus (FeSV), w h ich rapidly in d u ces fibrosarcom as. Infection w ith FeLV and its a ssociated viru ses is a sign ifican t cause o f m orb id ity and m ortality in dom estic cats. J F e lin e im m u n o d e fic ie n c y v ir u s b e lo n g s to th e le n tiv ir u s su b fa m ily L entiviruses infect a broad range of m am m als and in clu d e hum an (HIV), sim ian S t a w 3 7 m e (BIV) Lmmunodeficiency viruses, equine in fectiou s anem ia virus S m^d i-v i s n a virus (M W) o f sheep, and caprine arthritis-encephalitis virus (CAEV). The im m unod efien cy disease resulting from FIV infection in dom estic cats is sim ila r to h u m an acquired im m u n e d eficien cy syn d rom e (A ID S) a n d thus p rovides a useful anim al m od el for HIV infection and AIDS, i , C linically, FeLV and FIV infection s in cats h ave very sim ilar p resentations although there are som e distinct differences. The follow in g discussion w ill com pare and contrast these 2 im portant feline retroviruses. FELINE LEUKEMIA VIRUS Feline leukem ia virus is associated w ith both neoplastic and non n eop lastic (im m u n osu p p ressive) d iseases in the cat. Isolates of FeLV can be d iv id e d in to 3 subgroups (A, B, and C) according to in vitro host-range characteristics. Subgroup A
Javma-journal of The American Veterinary Medical Association, Nov 14, 1991
Feline sera were submitted to the Cornell Feline Health Center (n = 497) or to the New York State... more Feline sera were submitted to the Cornell Feline Health Center (n = 497) or to the New York State Diagnostic Laboratory (n = 1,565) for feline immunodeficiency virus (FIV) testing. Some sera (n = 166) were submitted for confirmation of previous FIV-positive results; 151 of these sera had been tested at the referring veterinary practice or laboratory, using an in-house ELISA. Excluding the samples submitted for confirmation, a total of 173 samples (9.1%) were FIV-positive; 11.6% of the clinically ill or high-risk cats and 0.49% of the healthy, low risk cats were positive for FIV antibody. A commercially available ELISA for detection of antibody to FIV was evaluated in relation to the immunofluorescent antibody (IFA) test and the immunoblot assay. The ELISA was interpreted according to the manufacturer's instructions, with the ratio of sample optical density to positive control optical density (S/P) determining a positive or negative result. The ELISA results based on the S/P interpretation were compared with a kinetics-based (KELA) interpretation of the ELISA. The KELA values were reported as positive, negative, or equivocal. Using the immunoblot as the standard, ELISA (S/P interpretation) had sensitivity of 0.93 and specificity of 0.98, whereas the IFA test had sensitivity of 0.95 and specificity of 0.98. However, the sensitivity and specificity of the ELISA (S/P interpretation) were markedly reduced for sample results falling in the KELA equivocal range, indicating that equivocal results were valid interpretations for some sera. A high number (22.5%) of the samples submitted for confirmation of a positive result from use of the in-house ELISA were determined to be negative for FIV antibody.(ABSTRACT TRUNCATED AT 250 WORDS)
Drug abuse is a common method of human immunodeficiency virus type 1 transmission, but the role o... more Drug abuse is a common method of human immunodeficiency virus type 1 transmission, but the role of opiates on lentivirus disease progression is not well understood. The feline immunodeficiency virus (FIV)/cat system was used to model the weekend opiate abuser: the nondependent, nonaddicted, and nontolerant person. Sixteen cats were placed into 4 groups: FIV only, morphine only, morphine/FIV, and controls. Multiple acute morphine exposure did not increase the severity of early lentivirus infection. On the contrary, it delayed or moderated the FIV-induced disease progression. Although the animals were exposed to only 1 injection of morphine per day for 2 consecutive days per week, the morphine-treated FIV-infected animals had a delayed onset of the FIV-induced lymphadenopathy, did not develop or had a significant delay in the FIV-induced effects on brain stem auditory evoked potentials, and demonstrated a trend toward decreased virus load.
Drug abuse is an important route of exposure to human immunodeficiency virus-1 (HIV-1). However, ... more Drug abuse is an important route of exposure to human immunodeficiency virus-1 (HIV-1). However, the role that drugs of abuse play in lentivirus disease progression remains unclear. There is a pressing need for appropriate animal models to examine the role of drugs of abuse on lentivirus disease progression. The feline immunodeficiency virus (FIV)/cat model is a legitimate system for the
Feline immunodeficiency virus (FIV), a lentivirus, causes progressive immunosuppression and neuro... more Feline immunodeficiency virus (FIV), a lentivirus, causes progressive immunosuppression and neurologic dysfunction in cats. Glucocorticoids are common therapeutic agents that are also immunosuppressive, and their use might enhance the pathogenic effects of lentivirus infections. Methylprednisolone acetate, a long-acting glucocorticoid, was administered to cats before FIV inoculation, and the course of early infection was monitored. The humoral immune response to FIV was not affected by corticosteroid treatment, but CD8 + cell-mediated antiviral activity was poor in cultures from FIV-infected cats treated with methylprednisolone. Steroidtreated cats had higher plasma viral RNA levels than untreated cats during acute viremia. In contrast, FIV-associated changes in brain stem auditory-evoked potentials were slow to develop in the methylprednisolone-treated cats. Methylprednisolone treatment of cats with established FIV infections appeared to reverse these neurophysiologic changes. These results emphasize the complexity of host-lentivirus interactions and suggest potential advantages and drawbacks of using glucocorticoids in lentivirus infections. Feline immunodeficiency virus (FIV), a lentivirus of cats that causes a disease similar to human AIDS [1], has been developed as a naturally occurring small animal model for human immunodeficiency virus (HIV) infection and disease [2-5]. Cats infected with FIV progress from acute to asymptomatic infection, followed by increasing immune system dysfunction and finally AIDS. As with HIV infection, the course of disease development is prolonged, taking several years in most cats to reach the AIDS stage. During that time, CD4 ϩ cells decline, cytokine profiles change, and macrophage functions are disrupted [5-8]. The virus also perturbs neurologic function, with changes in sleep patterns, brain stem auditory-evoked potentials (BAEPs), and spinal cord-evoked potentials occurring early in the acute and asymptomatic phases of infection [4, 9-11]. Glucocorticoid response elements are present in the promoters of several mammalian retroviruses, including 3 potential regions in the HIV-1 long terminal repeat (LTR) [12]. Another
Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direc... more Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direct effects of opiates on HIV infection are difficult to determine epidemiologically, animal models of lentivirus infection are relied upon to study the effects of opiates in the absence of confounding factors. Morphine, the predominant metabolite of heroin, is used in most experimental systems examining heroin abuse. In this study, morphine treatment of feline immunodeficiency virus (FIV)-infected cats modeled a typical pattern of escalating drug use interspersed with withdrawals. Plasma cortisol levels were measured for evidence of stress associated with morphine withdrawal. In the morphine-treated cats, cortisol levels peaked at time points corresponding to morphine withdrawal and returned to baseline levels during treatment and several weeks after the final withdrawal. Morphine-treated cats displayed clear behavioral and physical signs of opiate exposure and evidence of withdrawal when the drug was stopped. Morphine-exposed cats did not experience enhanced severity of FIV-related disease; in fact, morphine demonstrated a protective effect on FIV-associated changes in brainstem auditory evoked potentials. Our research suggests that opiate exposure is unlikely to adversely affect the progression of acute lentivirus infection and might be beneficial in controlling associated neurological disease.
Use of methamphetamine is increasingly a significant factor for the spread of human immunodeficie... more Use of methamphetamine is increasingly a significant factor for the spread of human immunodeficiency virus type 1, for in certain populations, there is a convergence of methamphetamine abuse with human immunodeficiency virus type 1 infection. Methamphetamine and human immunodeficiency virus type 1 are both individually neuropathogenic, and the neuropathology caused by these two agents occurs in overlapping brain regions. However, the biological interaction of methamphetamine with lentiviruses remains unknown. Here, we investigate the effects of simultaneous exposure of these two agents on disease progression using the feline immunodeficiency virus model. The study models the bingeing methamphetamine user with sequential and repeatedepisodes of use, which were interrupted by periods of abstinence. Methamphetamine exposure significantly accelerated and enhanced the severity of the feline immunodeficiency virus model-induced central nervous system functional pathology, as measured in delays in brainstem auditory evoked potentials. Reciprocally, feline immunodeficiency virus enhanced the severity of the methamphetamine-induced effects on brain monoamine neurotransmitter and dopamine transporter levels. The results of this study indicate that a dual potentiation occurred. That is, methamphetamine enhanced feline immunodeficiency virus model-induced central nervous system disease and feline immunodeficiency virus model enhanced the toxic effects of methamphetamine, heralding a significant concern for those individuals that are exposed to both agents.
Journal of the American Veterinary Medical Association, Jan 15, 1993
The course of naturally acquired infection with feline immunodeficiency virus was monitored in a ... more The course of naturally acquired infection with feline immunodeficiency virus was monitored in a cat over an 18-month period after diagnosis. The cat was admitted with diarrhea, poor body condition, a bite wound abscess, gingivitis, chronic fever, and splenomegaly. The cat's condition improved after splenectomy and remained stable for approximately 15 months, then began to deteriorate, as gingivitis, polyuria, polydipsia, pyrexia, multiple cutaneous masses, and hind limb paresis developed. The in vitro response of the cat's lymphocytes to mitogens was suppressed, and absolute lymphocyte counts were low. Spinal lymphosarcoma, disseminated mastocytoma, and presumptive diabetes mellitus were diagnosed after euthanasia. Decreased immune surveillance associated with feline immunodeficiency virus-related immunosuppression possibly played a role in the development of neoplastic disease in this cat.
Lymphocytes from normal cats or cats experimentally infected with feline immunodeficiency virus (... more Lymphocytes from normal cats or cats experimentally infected with feline immunodeficiency virus (FIV) were stimulated with phytohemagglutinin, pokeweed mitogen, or concanavalin A. Lymphocytes from infected cats had lower responses than those from uninfected cats. These results support the hypothesis that FIV induces immunosuppression.
A total of 878 samples from the New York State Diagnostic Laboratory (NYSDL), dating from January... more A total of 878 samples from the New York State Diagnostic Laboratory (NYSDL), dating from January 1984 to May 1987, were examined to detect antibodies to feline immunodeficiency virus (FIV). We used 2 screening methods; an indirect immunofluorescence assay (IFA) and an enzyme-linked immunosorbent assay (ELISA). Of these, 211 samples were from cats that tested negative for feline leukemia virus (FeLV) and exhibited disease signs consistent with immunodeficiency disease; 19 (9.0%) serum samples were determined to be positive. An additional 508 samples were from cats that tested FeLV-negative and were asymptomatic; 6 (1.2%) sera were determined to be positive. The final 159 samples were from FeLV-positive cats and included symptomatic and asymptomatic animals; this population of cats produced 6 (3.8%) positives. Additionally, 521 samples from the Cornell Feline Health Center (CFHC) serum bank, dating back to 1966, were tested to determine the earliest sample in which FIV antibodies cou...
Despite its fundamental importance, the educational mission of most schools of veterinary medicin... more Despite its fundamental importance, the educational mission of most schools of veterinary medicine receives far less recognition and support than the missions of research and discovery. This disparity is evident in promotion and tenure processes. Despite the frequent assertion that education is every college’s core mission, there is a broad consensus that faculty are promoted primarily on the basis of meeting expectations relative to publications and grant funding. This expectation is evident in the promotion packets faculty are expected to produce and the criteria by which those packets are reviewed. Among the outcomes is increasing difficulty in hiring and retaining faculty, including young clinicians and basic scientists who are drawn to academic institutions because of the opportunity to teach. The Regional Teaching Academy (RTA) of the West Region Consortium of Colleges of Veterinary Medicine initiated an inter-institutional collaboration to address the most important obstacles...
Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direc... more Opiate abuse is a risk factor for human immunodeficiency virus (HIV) infection. Because the direct effects of opiates on HIV infection are difficult to determine epidemiologically, animal models of lentivirus infection are relied upon to study the effects of opiates in the absence of confounding factors. Morphine, the predominant metabolite of heroin, is used in most experimental systems examining heroin abuse. In this study, morphine treatment of feline immunodeficiency virus (FIV)-infected cats modeled a typical pattern of escalating drug use interspersed with withdrawals. Plasma cortisol levels were measured for evidence of stress associated with morphine withdrawal. In the morphine-treated cats, cortisol levels peaked at time points corresponding to morphine withdrawal and returned to baseline levels during treatment and several weeks after the final withdrawal. Morphine-treated cats displayed clear behavioral and physical signs of opiate exposure and evidence of withdrawal when the drug was stopped. Morphine-exposed cats did not experience enhanced severity of FIV-related disease; in fact, morphine demonstrated a protective effect on FIV-associated changes in brainstem auditory evoked potentials. Our research suggests that opiate exposure is unlikely to adversely affect the progression of acute lentivirus infection and might be beneficial in controlling associated neurological disease.
How are cats infected with FPV? FPV can survive in the environment for up to a year and a special... more How are cats infected with FPV? FPV can survive in the environment for up to a year and a specialised disinfectant is required to kill it. Most cats contract FPV from a contaminated environment via infected faeces rather than from direct contact with infected cats.
A feline immunodeficiency virus-like virus (FIV-Oma) isolated from a Pallas' cat (Otocolobus manu... more A feline immunodeficiency virus-like virus (FIV-Oma) isolated from a Pallas' cat (Otocolobus manul) is highly cytopathic in CrFK cells, in contrast to the chronic, noncytolytic infection established by an FIV isolate from a domestic cat (FIV-Fca). The virions have typical lentivirus morphology, density, and magnesium-dependent reverse transcriptase activity. The major core protein is antigenically cross-reactive with that of FIV-Fca; however, FIV-Oma transcripts do not cross-hybridize with FIV-Fca. A conserved region of the FIV-Oma pol gene has 76 to 80% nucleic acid identity with the corresponding pol regions of other feline lentiviruses and 64 to 69% identity with those of human, ovine, and equine lentiviruses.
Background: Papillomaviruses (PVs) are a group of small, non-encapsulated, species-specific DNA v... more Background: Papillomaviruses (PVs) are a group of small, non-encapsulated, species-specific DNA viruses that have been detected in a variety of mammalian and avian species including humans, canines and felines. PVs cause lesions in the skin and mucous membranes of the host and after persistent infection, a subset of PVs can cause tumors such as cervical malignancies and head and neck squamous cell carcinoma in humans. PVs from several species have been isolated and their genomes have been sequenced, thereby increasing our understanding of the mechanism of viral oncogenesis and allowing for the development of molecular assays for the detection of PV infection. In humans, molecular testing for PV DNA is used to identify patients with persistent infections at risk for developing cervical cancer. In felids, PVs have been isolated and sequenced from oral papillomatous lesions of several wild species including bobcats, Asian lions and snow leopards. Since a number of wild felids are endan...
The nucleotide sequence and genomic organization have been determined for a highly cytopathic fel... more The nucleotide sequence and genomic organization have been determined for a highly cytopathic feline immunodeficiency virus (FIV) isolated from a Pallas ’ cat. The 9747-bp provirus of this virus, FIV-Oma, has typical lentivirus organization with LTRs, gag, pol, and env open reading frames (ORFs), putative vif and rev ORFs, and an ORF similar to ORF2/ORFA of domestic cat FIV isolates. Although the FIV-Oma provirus is 300 to 600 bp longer than other FIV proviruses, these additional bases are distributed throughout the genome. Phylogenetic analysis of a conserved region of the pol gene suggests that FIV-Oma is more closely related to some of the puma and lion lentiviruses than it is to domestic cat FIV isolates; however, many regions of the genome exhibit extensive nucleotide sequence divergence. None of the eight molecular proviral clones isolated from a genomic library are infectious, but we have constructed an infectious, cytopathic clone of FIV-Oma from subcloned and PCR-amplified ...
C on d en sed from "Feline Viral D iseases," T extbook o f V eterinary Internal M ed icin e, 4th ... more C on d en sed from "Feline Viral D iseases," T extbook o f V eterinary Internal M ed icin e, 4th E dition, 1994 Feline leukem ia virus (FeLV) and felin e im m u n o d eficien cy viru s (FIV) are retroviruses w h ich infect dom estic cats and produce disease, u su ally fo llo w in g an asym ptom atic period of m onths to years. The retrovirus fam ily (the Retroviridae) uses reverse transcriptase, an R N A-depend en t D N A p olym erase' (po I), to produce a d ou b le-stran d ed D N A copy o f the virion R N A. T he nam e retrovirus is d eriv ed from this "backwards" flo w of inform ation from R N A to D N A. The D N A copy, called a provirus, integrates into the host cell chrom asom es and thus can replicate along w ith the infected host cell. R etroviru ses are d iv id e d in to three su b fa m ilie s, the Spumuvirinae, the Oncornavirinae, and the Lentivirinae, based on shared p h ysical and b ioch em ical prop erties. Cats are su scep tib le to in fe c tio n by v ir u se s from ea ch o f th ese subfam ilies. Feline syn cytiu m-fo rm in g viru s (FeSFV), a sp u m a v iru s or "foamy virus," has b e e n iso la te d from both h ea lth y and d ise a se d cats. In so m e cat pop u lation s, the in fection rate in older cats m ay be 70% or greater. In general, FeSFV is considered to have little or no p athogenicity in dom estic cats. C hronic progressive polyarthritis has been linked w ith FeSFV infection but the d isea se has not been reproduced by experim ental FeSFV infection. M any o n c o g e n ic a n im a l retro v ir u se s, in c lu d in g FeLV, b e lo n g to th e oncovirus subfam ily. Three types of feline oncoviruses have been described: (1) the en d ogen ou s oncoviruses, such as RD114, w hich are present in all felin e cells but do not replicate or cause disease; (2) the exogen ou s, replication-com petent oncovirus, FeLV; and (3) the exogen ou s, rep lication-d efective on coviruses, in c lu d in g felin e sarcom a virus (FeSV), w h ich rapidly in d u ces fibrosarcom as. Infection w ith FeLV and its a ssociated viru ses is a sign ifican t cause o f m orb id ity and m ortality in dom estic cats. J F e lin e im m u n o d e fic ie n c y v ir u s b e lo n g s to th e le n tiv ir u s su b fa m ily L entiviruses infect a broad range of m am m als and in clu d e hum an (HIV), sim ian S t a w 3 7 m e (BIV) Lmmunodeficiency viruses, equine in fectiou s anem ia virus S m^d i-v i s n a virus (M W) o f sheep, and caprine arthritis-encephalitis virus (CAEV). The im m unod efien cy disease resulting from FIV infection in dom estic cats is sim ila r to h u m an acquired im m u n e d eficien cy syn d rom e (A ID S) a n d thus p rovides a useful anim al m od el for HIV infection and AIDS, i , C linically, FeLV and FIV infection s in cats h ave very sim ilar p resentations although there are som e distinct differences. The follow in g discussion w ill com pare and contrast these 2 im portant feline retroviruses. FELINE LEUKEMIA VIRUS Feline leukem ia virus is associated w ith both neoplastic and non n eop lastic (im m u n osu p p ressive) d iseases in the cat. Isolates of FeLV can be d iv id e d in to 3 subgroups (A, B, and C) according to in vitro host-range characteristics. Subgroup A
Uploads
Papers by Margaret Barr