Antibody response to reverse transcriptase in cats infected with feline immunodeficiency virus.
The antibody response in cats to feline immunodeficiency virus (FIV) reverse transcriptase (RT) was followed for 3 years. Eight of the nine cats used in this study produced reverse transcriptase-inhibiting (RTI) antibodies. Relative inhibitory means of 2.9%, 18.4%, 33%, and 47% were found 6, 12, 24, and 36 months, respectively, after infection with FIV. The enzyme activity was suppressed by greater than or equal to 78% with the use of 100 micrograms of FIV-associated IgG. The RTI antibodies were FIV-specific, as they did not inhibit other mammalian retroviral polymerases, including feline leukemia virus RT. An RT-inhibition assay with sera in the presence of protein A and immunoblot analysis showed that antibody binding to FIV RT protein p62 is independent of antibody ability to block enzyme activity. Viral RT released by detergent-treated virus was stable for more than 6 weeks at 4 degrees C, whereas its activity was reduced by 50% after 2 weeks at 37 degrees C. Because significant concentrations of RTI antibodies are detected only at 1 to 2 years after infection, they can be used to determine the approximate time of virus infection and as a marker for disease progression.
Fevereiro
M
M
Department of Veterinary Microbiology, Immunology and Parasitology, New York State College of Veterinary Medicine, Cornell University, Ithaca.
Roneker
C
C
de Noronha
F
F
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis*; D016516:CD4-CD8 Ratio; D002415:Cats; D016181:Feline Acquired Immunodeficiency Syndrome / Q000276:immunology*; D016089:Immunodeficiency Virus, Feline / Q000201:enzymology / Q000276:immunology*; D005256:Leukemia Virus, Feline / Q000201:enzymology / Q000276:immunology; D008979:Moloney murine leukemia virus / Q000201:enzymology; D012194:RNA-Directed DNA Polymerase / Q000276:immunology* / Q000302:isolation & purification; D012190:Retroviridae / Q000201:enzymology; D012191:Retroviridae Proteins / Q000037:antagonists & inhibitors / Q000276:immunology* / Q000302:isolation & purification; D018894:Reverse Transcriptase Inhibitors; D013047:Specific Pathogen-Free Organisms
D000914:Antibodies, Viral; D012191:Retroviridae Proteins; D018894:Reverse Transcriptase Inhibitors; D012194:RNA-Directed DNA Polymerase