The CD8+ cell phenotype mediating antiviral activity in feline immunodeficiency virus-infected cats is characterized by reduced surface expression of the CD8 beta chain.
The acute stage of feline immunodeficiency virus (FIV) infection is characterized by a CD8+ anti-FIV response that parallels the appearance of a CD8+ subpopulation with reduced expression of the beta chain (CD8 alpha + beta lo). The relationship between the CD8 alpha + beta lo phenotype and CD8+ anti-FIV activity was examined. Flow cytometric analysis of peripheral blood mononuclear cells with anti-CD8 beta chain monoclonal antibody 117 revealed that the CD8 alpha + beta lo phenotype expanded throughout the asymptomatic infection, constituting 80%-90% of the CD8 beta + cells in long-term-infected cats. Purified CD8 alpha + beta hi and CD8 alpha + beta lo subpopulations were analyzed for anti-FIV activity in an acute infection assay. Anti-FIV activity resided principally in the CD8 alpha + beta lo population and was demonstrated in acute FIV infections, as well as in long-term asymptomatic infections. These data suggest that a unique CD8 alpha + beta lo anti-FIV phenotype arises early in infection and may play a major role in eliminating virus and maintaining the asymptomatic infection.
Bucci
J G
JG
College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
Gebhard
D H
DH
Childers
T A
TA
English
R V
RV
Tompkins
M B
MB
Tompkins
W A
WA
D000208:Acute Disease; D000818:Animals; D000918:Antibody Specificity; D016827:CD8 Antigens / Q000096:biosynthesis* / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002353:Carrier State; D002415:Cats; D015536:Down-Regulation; D016181:Feline Acquired Immunodeficiency Syndrome / Q000276:immunology*; D005434:Flow Cytometry; D007111:Immunity, Cellular; D016089:Immunodeficiency Virus, Feline / Q000302:isolation & purification; D010641:Phenotype
D016827:CD8 Antigens