Pneumonia Vaccine in Aging HIV Positive Individuals

The investigators hypothesized that vaccination with either the 23-valent pneumococcal polysaccharide vaccine (PPV23) alone or the 13-valent pneumococcal conjugate vaccine (PCV 13) followed by PPV23 results in similar antibody levels/functional activity and induce a similar pneumococcal polysaccharide (PPS)-specific B cell response in HIV-positive individuals \>50 years of age and HIV-negative persons\>50 years of age. The investigators immunized the study group HIV+ persons\>50 and controls (HIV negative \>50 years) with PCV13 followed by PPV23 and HIV+\>50 with PPV23 alone. The investigators examined immune responses to PPS23F and PPS14 on a quantitative and qualitative level using ELISA and opsonophagocytic assays (OPA). To test the hypothesis that the levels of antigen specific B cells identified with PPS were comparable between the PPV23 and PCV13 vaccine recipients. Pre- and post-immunization peripheral blood samples were obtained. Extensive B cell phenotype analysis using fluorescent antibodies was used to characterize PPS-labeled B cells. Specific phenotypes were correlated with antibody levels and OPA and compared to historic populations immunized with PPV.