Poor HIV control in HLA-B*27 and B*57/58 noncontrollers is associated with limited number of polyfunctional Gag p24-specific CD8+ T cells.
OBJECTIVE
Analysis of immune response in HIV controllers, a unique group of infected individuals who are able to control HIV naturally, has provided us a chance to investigate the roles of host immune responses in HIV control.


METHODS
In this study, the functional quality of HIV Gag p24-specific CD8 T-cell responses was assessed in two groups of clinically distinct, HLA-B*27, HLA-B*57/58-matched individuals, viremic controllers [plasma HIV load (pVL) ≤ 2000 copies/ml) and noncontrollers (pVL >2000 copies/ml) to determine its impacts on natural HIV clinical outcome.


METHODS
An ex-vivo interferon (IFN)-γ ELISpot assay was used to screen for each individual's HIV Gag p24-specific T-cell responses. Intracellular cytokine staining assay was used to determine their functional quality (as number of cytokine being produced).


RESULTS
We found that, in contrast to previous studies, all Thai volunteers with HLA-B*5801 were uniformly noncontrollers. Viremic controllers were observed with a significantly larger number of high functional quality p24-specific CD8 T cells than noncontrollers (P < 0.05). This superior quality of responses was observed at both total p24 and epitope-specific level. Moreover, the absolute number of high functional quality Gag p24-specific CD8 T cells was significantly in a negative correlation with pVL (r = -0.6984, P = 0.0006) and also in a positive correlation with CD4 T-cell count (r = 0.5648, P = 0.0095).


CONCLUSIONS
We concluded that an adequate number of high functional quality Gag p24-specific CD8 T cells is strongly associated with a natural HIV controller status.
Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Navapon
N
Techakriengkrai
Yada
Y
Tansiri
Pokrath
P
Hansasuta
D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D016655:HIV Core Protein p24 / Q000276:immunology*; D015658:HIV Infections / Q000235:genetics / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology* / Q000502:physiology; D015235:HLA-B Antigens / Q000378:metabolism; D015796:HLA-B27 Antigen / Q000378:metabolism; D054884:Host-Pathogen Interactions / Q000235:genetics / Q000276:immunology*; D006801:Humans; D018928:Immunity, Mucosal / Q000235:genetics / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D019562:Viral Load; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*
D016655:HIV Core Protein p24; D015235:HLA-B Antigens; D015796:HLA-B27 Antigen; C103707:HLA-B57 antigen; C041533:HLA-B58 antigen; D054301:gag Gene Products, Human Immunodeficiency Virus