25 Of the many pneumococcal

secreted or surface-expressed proteins, including LytC, PcsB, that have been identified as potential vaccine antigens, 26, 27, 28 and 29 work described here was limited to only 4 antigens due to sample constraints. These protein antigens were chosen because they are well characterized as playing a role in the pathogenesis of pneumococcal disease and demonstrated to be protective against carriage and/or invasive disease in humans and/or animal models. 30, 31, 32 and 33 Knowledge gained from these 4 protein antigens may be applicable to other novel protein vaccine candidates, as most of these protein antigens are fairly conserved among all pneumococcal isolates. A cocktail of 10 ug/ml tuberculin purified protein derivative (PPD; Statens Serum Ins.), 5 ug/ml purified tetanus toxoid (Merck Biosciences) and 1 ug/ml inactivated split virion influenza vaccine (Flu; Aventis Target Selective Inhibitor Library screening Pasteur MSD) was used as a positive control and PBS alone as a negative control. As PBS generated very few spots, background was not subtracted. As the total number of cells recovered from each blood sample varied, it was not always possible to include selleck kinase inhibitor all antigens in every assay. ASC were detected by incubation with IgG secondary antibody (Sigma) conjugated to alkaline phosphatase for

at least 6 h prior to development with an alkaline phosphatase substrate kit (Bio-Rad). ASC were counted using an AID ELISPOT reader and analysis software version 4.0 (AID Strasburg, Germany). Data were expressed as medians and interquartile ranges (IQR). Comparisons were made Immune system using Friedman’s test to evaluate the effect of ART across all time points (i.e. at baseline and all 3 follow-up times). Statistical analysis and graphical presentations were done using Stata 10 and GraphPad Prism software (version 4.0). Differences after comparisons were considered statistically significant if P < 0.05. Of the 45 children recruited, 2 died, 1 moved away from

Blantyre and 1 withdrew from the study. These 4 children were excluded from subsequent analysis and 41 HIV-infected children with median age 92 months at recruitment (IQR, 63–132 months) were included. None of these 41 children was malaria parasitemic at enrollment, all received cotrimoxazole prophylaxis and none were febrile at any of the follow-up visits. 18/41 (44%) were females and 23/40 (58%) had S. pneumoniae detected by culture of a nasopharyngeal swab obtained at enrollment. Pneumococcal carriage rates varied between 58 and 92% throughout the course of the study and the rate was 83% after 12 months of ART. The carriage rate in healthy controls with median age 92 months (IQR, 54–132 months) was 46%. 10 As expected, both absolute and percentage CD4+ T cell counts rose significantly (P < 0.