Progressive expansion of an L-selectin-negative CD8 cell with anti-feline immunodeficiency virus (FIV) suppressor function in the circulation of FIV-infected cats.
The acute stage of feline immunodeficiency virus (FIV) infection is characterized by the appearance of a major CD8 subpopulation with reduced expression of the CD8 beta chain (CD8alpha+betalo). CD8 antiviral activity was subsequently shown to be mediated by the CD8alpha+betalo phenotype, which is the dominant CD8 phenotype in long-term infected cats. Two- and three-color flow cytometric analysis demonstrated that the CD8alpha+betalo subset is L-selectin negative (CD62L-) and has increased expression of CD44, CD49d, and CD18, consistent with an activation phenotype. The CD8alpha+betaloCD62L- cells but not the CD8alpha+betahiCD62L+ cells demonstrated strong antiviral activity in the FIV acute-infection assay. The progressive expansion of the CD8alpha+betaloCD62L- effector subset cells in FIV-infected cats parallels that seen in human immunodeficiency virus (HIV)-infected patients, suggesting that failure in homeostatic mechanisms regulating lymphocyte activation or trafficking (or both) may be a consequence of both HIV and FIV infections.
Gebhard
D H
DH
Department of Microbiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA.
Dow
J L
JL
Childers
T A
TA
Alvelo
J I
JI
Tompkins
M B
MB
Tompkins
W A
WA
D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002415:Cats; D016181:Feline Acquired Immunodeficiency Syndrome / Q000276:immunology*; D016089:Immunodeficiency Virus, Feline / Q000276:immunology*; D016130:Immunophenotyping; D016023:Integrins / Q000378:metabolism; D019041:L-Selectin / Q000032:analysis*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008198:Lymph Nodes / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D016023:Integrins; D019041:L-Selectin