Induction and Expression of Intestinal Humoral Immunity in HIV-Infected Individuals: Prospects for Vaccination against Secondary Enteric Infections

In view of the high incidence and severity of AIDS-related mucosal complications and secondary mucosal infections, we have evaluated the impact of HIV infection on the mucosal humoral immune status. By measuring the number of total and specific antibody-secreting cells in duodenal biopsies, we could show that HIV infection induces a pronounced polyclonal B-cell activation already in the early stages of the disease. Furthermore, we could document normal mucosal B-cell responses following oral vaccination, also in the late stages of the disease, and despite a lack of concomitant systemic responses. The relevance of these observations will be discussed with respect to the possibility of vaccinating HIV-infected individuals against secondary opportunistic infections.