Mucosal and systemic HIV-1-specific immunity in HIV-1-exposed but uninfected heterosexual men.
BACKGROUND
Despite multiple, repeated exposures to HIV-1, some individuals never seroconvert. Mucosal and systemic immune correlates of this condition have been analysed in HIV-1-exposed women but no data are available concerning mucosal immunity and HIV-1-specific immune responses in exposed but uninfected men.


METHODS
We analysed cellular and humoral immune parameters in peripheral lymphocytes, seminal fluid and urethral swabs of 14 recently HIV-1-exposed seonegative (ESN) heterosexual men, seven HIV-seropositive patients and seven healthy controls.


RESULTS
HIV-1-specific IgA were detected in urethral swabs of 11 out of 14 ESN and of six out of seven HIV-seropositive patients; Env- and Gag-specific IFNgamma-producing CD4 and CD8 peripheral lymphocytes were present in ESN and HIV-seropositive patients; seminal lymphocytes, but not peripheral blood lymphocytes, of ESN were enriched in activated populations (CD8CD38RO and CD4CD25). p24-specific cytotoxic T lymphocytes were correlated with the percentage of CD4 in the HIV-seropositive partners. High urethral concentrations of HIV-1-specific IgA were seen in those ESN with the most recent unprotected sexual episode.


CONCLUSIONS
This is the first report of HIV-specific mucosal immunity in ESN men. These data add to the body of knowledge of the immune correlates present in exposed, uninfected individuals and might be important in vaccine design.
Lo Caputo
Sergio
S
Unitá Operativa Malattie Infettive, Ospedale SM Annunziata, Firenze, Milano, Italy.
Trabattoni
Daria
D
Vichi
Francesca
F
Piconi
Stefania
S
Lopalco
Lucia
L
Villa
Maria Luisa
ML
Mazzotta
Francesco
F
Clerici
Mario
M
D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016022:Case-Control Studies; D015488:HIV Antigens / Q000494:pharmacology; D018023:HIV Seronegativity / Q000276:immunology*; D006679:HIV Seropositivity / Q000276:immunology; D015497:HIV-1; D020010:Heterosexuality; D006801:Humans; D018928:Immunity, Mucosal; D007070:Immunoglobulin A / Q000032:analysis*; D016130:Immunophenotyping; D007371:Interferon-gamma / Q000096:biosynthesis; D008297:Male; D012661:Semen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014521:Urethra / Q000276:immunology
D015488:HIV Antigens; D007070:Immunoglobulin A; D007371:Interferon-gamma