Abraham AG, et al. - In view of the observation that vitamin D has immunoregulatory functions, including inducing the development of T cells, researchers assessed if higher levels of vitamin D may improve CD4+ rebound among HIV-infected HAART initiators. They performed a longitudinal study of men from the Multicenter AIDS Cohort Study who were virally suppressed following HAART initiation and had pre-HAART and post-HAART 25(OH)D and 1,25(OH)2D measurements and repeated measures of CD4+. No evidence suggested the association of higher vitamin D metabolite levels pre-HAART or post-HAART with better CD4+ outcomes among these individuals.