IMPACT OF STREPTOCOCCUS-PNEUMONIAE BACTEREMIA AND HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 ON ORAL MUCOSAL IMMUNITY

To determine whether defects in mucosal immunity were associated with invasive disease caused by a mucosal pathogen, Streptococcus pneumonia e, levels of salivary immunoglobulins and nonspecific immune factors w ere compared in subjects with human immunodeficiency virus type 1 (HIV -1) infection and in HIV-1-seronegative subjects with and without pneu mococcal bacteremia. The IgA2 subclass may be of particular importance because S. pneumoniae produces IgA1 protease, which cleaves IgA1 but not IgA2. Levels (37-56 mu g/mL) and proportions (11%-17%) of IgA2 wer e similar among groups. Serotype-specific capsular salivary IgA was pr esent in a minority of patients with acute bacteremia. Levels of lacto ferrin were increased with bacteremia. Neither selective mucosal IgA2 deficiency nor impaired nonspecific upper respiratory mucosal response s were associated with invasive pneumococcal disease during HIV-1 infe ction; thus, other defects in mucosal cellular responses and systemic immunity may predispose HIV-1-infected patients to invasive pneumococc al disease.