Serological diagnosis of feline immunodeficiency virus infection based on synthetic peptides from Env glycoproteins

doi:10.1016/S0923-2516(06)80031-2

Research in Virology

Volume 144, 1993, Pages 209-218

Research in Virology

https://doi.org/10.1016/S0923-2516(06)80031-2 Get rights and content

Summary

Feline immunodeficiency virus (FIV) is a lentivirus which infects domestic cats, causing an acquired immunodeficiency syndrome (AIDS). The aim of the present work was the development of an immunoassay for the diagnosis of FIV infection, using synthetic peptides from FIV envelope (Env) glycoproteins. Four peptides (8 to 11 amino acids long) corresponding to group-specific epitopes of FIV Env extracellular (SU) or transmembrane (TM) glycoproteins were synthesized. They were evaluated by enzyme-linked immunosorbent assay (ELISA) for immunoreactivity with sera from naturally or experimentally FIV-infected cats.

One of these, P237, corresponds to a conserved nonapeptide of FIV TM, folded as a loop between two cysteines. ELISA performed with P237 on 171 sera from FIV-infected cats and 46 sera from specific-pathogen-free cats showed no false positive cases and 100 % detection of infected cat sera. Moreover, 47 pet cat sera which were negative with a whole virus-based-ELISA were tested with the P237 ELISA: 2 out of 47 showed reactivity. FIV infection of these two cats was confirmed by radio-immunoprecipitation assay. Temporal studies performed on serial serum samples from experimentally infected cats detected antibodies to P237 three to five weeks after inoculation of virus. Thus, the P237 ELISA is a sensitive and specific immunoassay for early detection of antibodies to FIV. In addition, this synthetic nonapeptide is easier to produce and purify than virus preparations or recombinant proteins.

Le virus de l'immunodéficience féline (VIF) est un lentivirus qui infecte les chats domestiques, provoquant un syndrome d'immunodéficience acquise (SIDA). Ce travail avait comme objectif le développement d'un test sérologique pour le diagnostic de l'infection par le VIF en utilisant des peptides synthétiques issus de la glycoprotéine d'enveloppe du VIF. Quatre peptides (d'une taille variant de 8 à 11 acides aminés) correspondant à des épitopes spécifiques de groupe de la protéine extracellulaire (SU) ou de la protéine transmembranaire (TM) ont été synthétisés. La réactivité de ces peptides avec des sérums de chats naturellement ou expérimentalement infectés par le VIF a été évaluée par ELISA.

Le nonapeptide P237 correspond à une région conservée de la TM du VIF, qui forme une boucle entre deux cystéines. Les tests sérologiques effectués sur P237 avec 171 sérums de chats infectés par le VIF et 46 sérums de chats d'élevage non infectés SPF (specific-pathogen free), ont mis en évidence une réactivité de 100 % des sérums des chats infectés et n'ont révélé aucun faux positif pour les chats non infectés.

De plus, sur 47 sérums de chats domestiques qui étaient négatifs dans un test ELISA basé sur du virus entier purifié, 2 ont été positifs dans le test ELISA avec P237. L'infection par le VIF de ces deux chats a été confirmée par immunoprécipitation. Des études cinétiques réalisées avec des prélèvements successifs de sérums de chats expérimentalement infectés par le VIF ont permis de détecter la présence d'anticorps anti-P237 entre 3 et 5 semaines après l'inoculation du virus. L'ELISA basé sur l'utilisation du peptide P237 est donc un test d'immunodiagnostic spécifique et sensible pour la détection d'anticorps dirigés contre le VIF. De plus, ce nonapeptide est plus facile à produire et à purifier que des préparations virales ou des protéines recombinantes.

References (34)

AvrameasA. et al.
Localisation of three epitopes of the Env protein of feline immunodeficiency virus
Mol. Immunol.
(1992)
MorikawaS. et al.
Identification of conserved and variable regions in the envelope glycoprotein sequences of two feline immunodeficiency viruses isolated in Zürich, Switzerland
Virus Res.
(1991)
PancinoG.F. et al.
Structure and variations of feline immunodeficiency virus envelope glycoproteins
Virology
(1993)
AckleyC.D. et al.
Identification of a CD4 homologue in the cat
J. Virol.
(1990)
BaillouA. et al.
Fine serotyping of human immunodeficiency virus serotype 1 (HIV-1) and HIV-2 infections by using synthetic oligopeptides representing an immunodominant domain of HIV-1 and HIV-2/simian immunodeficiency virus
J. Clin. Microbiol.
(1991)
BarloughJ.E. et al.
Acquired immune dysfunction in cats with experimentally induced feline immunodeficiency virus infection: comparaison of short-term and long-term infections
J. Acquired Immune Defic. Syndr.
(1991)
ChongY.H. et al.
Analysis of equine humoral immune response to the transmembrane envelope glycoprotein (gp45) of equine infectious anemia virus
J. Virol.
(1991)
FontenotJ.D. et al.
Evaluation of feline immunodeficiency virus and feline leukemia virus transmembrane peptides for serological diagnosis
J. Clin. Microbiol.
(1992)
FuruyaT. et al.
Detection of anti-gag antibodies of feline immunodeficiency virus in cats by enzyme-linked immunosorbent assay
Arch. Virol.
(1992)
GallaherW.R. et al.
A general model for the transmembrane proteins of HIV and other retroviruses
AIDS Res. Human Retrov.
(1989)

GnannJ.W. et al.

Synthetic peptide immunoassay distinguishes HIV type 1 and HIV type 2 infections

Science

(1987)

GnannJ.W. et al.

Fine mapping of an immunodominant domain in the transmembrane glycoprotein of human immunodeficiency virus

J. Virol.

(1987)

HosieM.J. et al.

Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus in cats in the United Kingdom

Vet. Rec.

(1989)

HosieM.J. et al.

Serological responses of cats to feline immunodeficiency virus

AIDS

(1990)

HurtrelM. et al.

Comparison of early and late feline immunodeficiency virus encephalopathies

AIDS

(1992)

IshidaT. et al.

Feline immunodeficiency virus infection in cats of Japan

Amer. J. Vet. Med. Ass.

(1989)

KiyomasuT. et al.

Identification of feline immunodeficiency virus rev gene activity

J. Virol.

(1991)

Cited by (32)

Amino acid variations of the immuno-dominant domain of respiratory syncytial virus attachment glycoprotein (G) affect the antibody responses In BALB/c mice
2023, Journal of Virological Methods
Respiratory syncytial virus (RSV) is the leading cause of respiratory illness in ruminants and infants. The G glycoprotein of RSV serves as the viral attachment ligand. Despite currently available vaccines, RSV immunity is insufficient, and re-infections occur. Vaccine studies employing the G-protein's 174–187 amino acids, representing the immunodominant domain, have protected mice and calves against infections. To investigate the causes of vaccination failure, we designed four synthetic peptides for the ruminant RSV isolates (391–2, Maryland-BRSV, European-BRSV, and ORSV) using the immune-dominant sequence and vaccinated mice groups with them. The produced antibodies targeting each peptide were evaluated using ELISA and flow cytometry to determine their reactivity against the linear antigen and the native form of the G protein, respectively. Antibodies responded to homologous and heterologous peptides as determined by ELISA. Using flow cytometry-analysis targeting the natively folded protein, most generated antibodies reacted only with their homologous strain. However, antibodies raised to 391–2 peptide reacted with homologous and heterologous Maryland-BRSV viral epitopes. Accordingly, inadequate immunity and recurring RSV infections might be attributed to variations of antibodies targeting the immunodominant region of the G-protein.
Prime-boost vaccination using DNA and whole inactivated virus vaccines provides limited protection against virulent feline immunodeficiency virus
2006, Vaccine
Protection against feline immunodeficiency virus (FIV) has been achieved using a variety of vaccines notably whole inactivated virus (WIV) and DNA. However protection against more virulent isolates, typical of those encountered in natural infections, has been difficult to achieve. In an attempt to improve protection against virulent FIV_GL8, we combined both DNA and WIV vaccines in a “prime-boost” approach. Thirty cats were divided into four groups receiving vaccinations and one unvaccinated control group. Following viral challenge, two vaccinated animals, one receiving DNA alone and one the prime-boost vaccine remained free of viraemia, whilst all controls became viraemic. Animals vaccinated with WIV showed apparent early enhancement of infection at 2 weeks post challenge (pc) with higher plasma viral RNA loads than control animals or cats immunised with DNA alone. Despite this, animals vaccinated with WIV or DNA alone showed significantly lower proviral loads in peripheral blood mononuclear cells and mesenteric lymph node cells, whilst those receiving the DNA–WIV prime-boost vaccine showed significantly lower proviral loads in PBMC, than control animals, at 35 weeks pc. Therefore both DNA and WIV vaccines conferred limited protection against viral challenge but the combination of WIV and DNA in a prime-boost approach appeared to offer no significant advantage over either vaccine alone.
Development of recombinant capsid antigen/transmembrane epitope fusion proteins for serological diagnosis of animal lentivirus infections
2004, Journal of Virological Methods
Among animal lentiviruses, Feline immunodeficiency virus (FIV), Equine infectious anaemia virus (EIAV) and Small ruminant lentiviruses (SRLV) are important pathogens associated with a variety of clinical pictures including immunodeficiency, anaemia, arthritis, pneumonia. The detection of viral antibody response represents a practical diagnostic approach in all lentivirus infections since they remain detectable long life. Capsid antigen (CA) is the major viral core protein and specific antibodies against this antigen are usually first recognised in infected sheep, goat and horse, remaining detectable for long period. Transmembrane (TM) domain of envelope glycoprotein contains a well conserved motif known to form an immunodominant epitope in several lentiviruses. In this study a simple strategy was developed to express the entire CA and the TM epitope in a single fusion protein from equine, feline and small ruminant lentiviruses in prokaryotic system and evaluated the diagnostic utility of a purified preparation in an indirect ELISA for each of the three infections. Results demonstrate that, for FIV and SRLV infections, the combination of CA and TM fractions increases the sensitivity of diagnostic tests based only on CA. The corresponding CA/TM antigen from EIAV showed excellent agreement with Coggins test.
Dissection of seroreactivity against the tryptophan-rich motif of the feline immunodeficiency virus transmembrane glycoprotein
2004, Virology
Immunogenicity of the tryptophan-rich motif (TrpM) in the membrane-proximal ectodomain of the transmembrane (TM) glycoprotein of feline immunodeficiency virus (FIV) was investigated. Peptide 59, a peptide containing the TrpM of the TM of FIV, was covalently coupled to Qβ phage virus-like particles (Qβ-59) in the attempt to induce potent anti-TrpM B cell responses in cats. All Qβ-59 immunized cats, but not cats that received a mixture of uncoupled Qβ and peptide 59, developed antibodies that reacted with a same epitope in extensive binding and binding competition assays. The epitope recognized was composed of three amino acids, two of which are adjacent. However, Qβ-59-immune sera failed to recognize whole FIV in all binding and neutralization assays performed. Furthermore, no reactivity against the TrpM was detected by screening sera from FIV-infected cats that had reacted with TM peptides, confirming that this epitope does not seem to be serologically functional in the FIV virion. The data suggest that TrpM may not be a suitable target for antiviral vaccine design.
A multivariate statistical analysis to follow the course of disease after infection of cats with different strains of the feline immunodeficiency virus (FIV)
2002, Journal of Virological Methods
A descriptive multivariate assay is described which is suitable to analyze results of a biological experiment with small sample size but high qualitative and quantitative complexity of variables. This type of assay allows evaluation of multiple variables observed in the course of an experimental virus infection (e.g. viremia, nucleic acid detection, antibody titers, clinical parameters, anti-microbial treatments or vaccination) in a single graph. In our study, a multiple correspondence analysis (MCA) was used to correlate a total of 145 measurements from each of a dozen of variables measured in five groups of three cats infected by five isolates of feline immunodeficiency virus (FIV). Three groups of virus isolates with distinct virulence were defined and correlation between dynamics of lymphocyte subset counts and viral virulence was established. Comparison between the primary stages of illness and follow-up examinations were of prognostic value and are thus helpful for development and monitoring of therapeutic strategies.
Protection against feline immunodeficiency virus using replication defective proviral DNA vaccines with feline interleukin-12 and -18
2002, Vaccine
A molecular clone of the Glasgow-8 isolate of FIV (FIV_GL8) was rendered replication defective by an in-frame deletion in either reverse transcriptase (ΔRT) or integrase (ΔIN) genes for use as DNA vaccines. To test the ability of these multi-gene vaccines to protect against two feline immunodeficiency virus (FIV) isolates of differing virulence, cats were immunized using either DNA vaccine alone or co-administered with interleukin-12 (IL-12) and/or interleukin-18 (IL-18) cytokine DNA. Animals were challenged sequentially with FIV-Petaluma (FIV_PET) an FIV isolate of relatively low virulence and subsequently with the more virulent FIV_GL8. A proportion of vaccinates (5/18 ΔIN and 2/12 ΔRT) were protected against primary challenge with FIV_PET. Five of the vaccinated-protected cats were re-challenged with FIV_PET; four (all ΔIN) remained free of viraemia whilst all naive controls became viraemic. Following subsequent challenge with the more virulent FIV_GL8 these four vaccinated-protected animals all became viraemic but showed lower proviral loads than naive cats. This study suggests that while our current DNA vaccines may not produce sterilizing immunity against more virulent isolates of FIV, they may nevertheless significantly reduce the impact of infection.

View all citing articles on Scopus

View full text

Serological diagnosis of feline immunodeficiency virus infection based on synthetic peptides from Env glycoproteinsDiagnostic sérologique de l'infection par le virus de l'immunodéficience féline (VIF) à l'aide de peptides synthétiques issus de la glycoprotéine d'enveloppe

Summary

Mol. Immunol.

Virus Res.

Virology

Identification of a CD4 homologue in the cat

J. Virol.

Fine serotyping of human immunodeficiency virus serotype 1 (HIV-1) and HIV-2 infections by using synthetic oligopeptides representing an immunodominant domain of HIV-1 and HIV-2/simian immunodeficiency virus

J. Clin. Microbiol.

Acquired immune dysfunction in cats with experimentally induced feline immunodeficiency virus infection: comparaison of short-term and long-term infections

J. Acquired Immune Defic. Syndr.

Analysis of equine humoral immune response to the transmembrane envelope glycoprotein (gp45) of equine infectious anemia virus

J. Virol.

Evaluation of feline immunodeficiency virus and feline leukemia virus transmembrane peptides for serological diagnosis

J. Clin. Microbiol.

Detection of anti-gag antibodies of feline immunodeficiency virus in cats by enzyme-linked immunosorbent assay

Arch. Virol.

A general model for the transmembrane proteins of HIV and other retroviruses

AIDS Res. Human Retrov.

Synthetic peptide immunoassay distinguishes HIV type 1 and HIV type 2 infections

Science

Fine mapping of an immunodominant domain in the transmembrane glycoprotein of human immunodeficiency virus

J. Virol.

Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus in cats in the United Kingdom

Vet. Rec.

Serological responses of cats to feline immunodeficiency virus

AIDS

Comparison of early and late feline immunodeficiency virus encephalopathies

AIDS

Feline immunodeficiency virus infection in cats of Japan

Amer. J. Vet. Med. Ass.

Identification of feline immunodeficiency virus rev gene activity

J. Virol.