Limited long-term naive CD4+ T cell reconstitution in patients experiencing viral load rebounds during HAART

Long-term (3.5 years) immune reconstitution in relation to viral load response was determined. Plasma HIV-1 RNA was suppressed in 40 patients (full responders) up to 42 months, and 17 patients achieved partial response. The measurements of CD4⁺ and CD8⁺ T lymphocyte subsets (CD45RA, CD45RACD62L, CD45RO, CD28, CD38) were carried out by flow cytometry. Full responders had a significant increase of CD4⁺ and all CD4⁺ T subsets both up to 6 and from 6 to 42 months, while the increase for partial responders was only up to 6 months. By 6 months, higher slopes were observed in full versus partial responders in the % of CD28 on CD4⁺ and the % of CD4⁺ memory subset and in both naïve and memory CD4⁺ subsets from 6 to 42 months. The percentage of CD8⁺ and its subsets was decreased significantly in full responders both up to 6 and from 6 to 42 months (except for an increase in the CD8⁺CD45RA⁺ CD62L⁺ cells), while in partial responders this decrease was only up to 6 months. Lower slopes were observed in full versus partial responders from 6 to 42 months in the percentages of CD8⁺, CD8⁺CD45RO⁺, CD8⁺CD28⁻, and CD8⁺CD38⁺ T cells. In conclusion, full responders have a stronger long-term naive CD4⁺ T cell subset reconstitution than partial responders. J. Med. Virol. 73:235–243, 2004. © 2004 Wiley-Liss, Inc.