The expression of a number of antigens was found to be significantly different between the groups. Relative expression refers to the difference in the average normalized intensities between the 2 groups. We observed no statistically significant differences between LTNP and first-line therapy and between LTNP and salvage therapy. For salvage therapy versus first-line treatment, CD135 was decreased in salvage therapy (relative expression - 1.3; P < .001). Other antigens, including some contained on this array, have been previously demonstrated (by flow cytometry) to be up- or down-regulated at different stages of infection, and we do not find statistical significance with many of these. While these data demonstrate discrepancies with such findings, we are performing statistical comparisons across 4 distinct infected groups. Further assays will involve a greater number of CD antigens and it is anticipated that the array itself could be subdivided into smaller subarrays such that linear antigen binding conditions and dynamics could be optimized for a greater number of CD antigens.