Induction of HIV-1-Specific Mucosal Immune Responses Following Intramuscular Recombinant Adenovirus Serotype 26 HIV-1 Vaccination of Humans
Year of Publication
Baden, L; Liu, J; Li, H; Johnson, J; Walsh, S; Kleinjan, J; Engelson, B; Peter, L; Abbink, P; Milner, Jr., D; Golden, K; Viani, K; Stachler, M; Chen, B; [...]; Wolff, M; Loblein, H; Seaman, M; Dolin, R; Barouch, D
J Infect Dis
adenovirus; HIV; mucosal immunity; vaccine
BACKGROUND: Defining mucosal immune responses and inflammation to candidate human immunodeficiency virus type 1 (HIV-1) vaccines represents a current research priority for the HIV-1 vaccine field. In particular, it is unclear whether intramuscular immunization can elicit immune responses at mucosal surfaces in humans. METHODS: In this double-blind, randomized, placebo-controlled clinical trial, we evaluated systemic and mucosal immune responses to a candidate adenovirus serotype 26 (Ad26) vectored HIV-1 envelop (Env) vaccine in baseline Ad26-seronegative and Ad26-seropositive healthy volunteers. Systematic mucosal sampling with rectal Weck-Cel sponges and rectal biopsies were performed. RESULTS: Intramuscular immunization elicited both systemic and mucosal Env-specific humoral and cellular immune responses in the majority of subjects. Individuals with preexisting Ad26-specific neutralizing antibodies had vaccine-elicited immune responses comparable to those of subjects who were Ad26 seronegative. We also observed no increase in activated total or vector-specific mucosal CD4(+) T lymphocytes following vaccination by either histopathology or flow cytometry. CONCLUSIONS: These data demonstrate that a single intramuscular administration of this Ad26-vectored HIV-1 Env vaccine elicited both systemic and mucosal immune responses in humans. Induction of antigen-specific humoral and cellular mucosal immunity was not accompanied by a detectable increase in mucosal inflammation.