ENV-specific cytotoxic T lymphocyte responses in HIV seronegative health care workers occupationally exposed to HIV-contaminated body fluids

• Published in: The Journal of clinical investigation Vol. 96; no. 2; pp. 867 - 876
• Main Authors: Pinto, L A, Sullivan, J, Berzofsky, J A, Clerici, M, Kessler, H A, Landay, A L, Shearer, G M
• Format: Journal Article
• Language: English
• Published: United States 01.08.1995
• Subjects: Accidents, Occupational; Adult; Amino Acid Sequence; Blood Donors; Body Fluids - virology; Female; Follow-Up Studies; Gene Products, env - immunology; Health Personnel; HIV Infections - prevention & control; HIV Infections - transmission; HIV Seronegativity - immunology; HIV-1 - immunology; HIV-1 - isolation & purification; Humans; Male; Medical Waste; Molecular Sequence Data; Needlestick Injuries - drug therapy; Needlestick Injuries - immunology; Occupational Exposure; Prospective Studies; Proviruses - isolation & purification; T-Lymphocytes, Cytotoxic - immunology; Zidovudine - therapeutic use
• ISSN: 0021-9738
• DOI: 10.1172/JCI118133

Identification of the components of protective immunity are crucial for the development of effective prophylactic and therapeutic vaccine strategies. Analysis of HIV-specific responses in exposed but uninfected individuals might thus provide a unique resource to elucidate the components and correlates of protective immunity to HIV. In the present study we analyzed HIV-specific cytotoxic and helper T lymphocyte responses in health care workers (HCW) exposed to body fluids from HIV-positive individuals. HCW exposed to blood from HIV-negative individuals as well as healthy donors served as controls. Cytotoxic T lymphocyte (CTL) responses to HIV envelope (env) peptides were detected in 7/20 (35%) HCW exposed to HIV-positive blood and in none of the 20 health care workers exposed to uninfected blood or the seven healthy blood donors studied. HIV-specific CTL responses were detected only after in vitro stimulation, and were MHC class I restricted. No MHC class I restriction elements were uniformly identified among the different responders. 21/28 (75%) HCW exposed to contaminated blood responded to env as measured by IL-2 production to the peptides, in contrast to only 9/38 (24%) HCW exposed to HIV seronegative blood and 3/35 (9%) healthy blood donors. All the HIV exposed individuals were seronegative on repeated ELISA tests, and no evidence of infection was obtained by PCR analysis. These findings indicate that a single exposure to HIV can induce CTL immunity to HIV antigens, in the absence of other evidence of infection.