Intracellular cytokines in the acute response to highly active antiretroviral therapy

Objectives: Successful highly active antiretroviral therapy (HAART) is usua lly associated with a rapid decline in HIV plasma RNA levels and a gradual increase in CD4 T cells. We examined whether changes in cytokine production and profile precede other immunological changes and whether these might oc cur in temporal association with plasma HIV RNA changes. Design and methods: Eleven HIV-1-infected patients were enrolled into a pro spective cohort study; eight patients were naive to antiretroviral therapy. Blood samples were collected pre-therapy (week 0) and at 1, 2, and 3 weeks post-initiation of therapy. Results: All 11 patients enrolled remained on triple HAART for 1 week, eigh t for 2 weeks, and six for greater than or equal to 3 weeks. When compared to week 0, these patients had a greater than or equal to 2-log(10) decline in HIV plasma RNA levels and/or a decline to less than or equal to 400 copi es/ml by week 3 of therapy (p = 0.004). The numbers and percentages of CD4 and CD8 T cells, and the percentage of naive, memory, and activated T cells did not change significantly between weeks 0 and 1 or 0 and 3. Of all the immune parameters examined only: the percentage of CD4 T cells spontaneousl y producing tumor necrosis factor (TNF)-alpha (median, 2.4 versus 0.5% P = 0.025); the percentage of CD8 T cells spontaneously producing TNF-alpha (me dian, 0.6 versus 0.2% P = 0.037); and the percentage of CD3 T cells spontan eously producing interleukin-4 (median, 1.8 versus 0.8% P = 0.004) changed significantly between weeks 0 and 3. Conclusions: In these patients, decreases in the percentage of T cells spon taneously producing TNF-alpha or interleukin-4 preceded changes in CD4 T ce lls. If confirmed by others, these observations may be useful as early pred ictors of response to and early failure of HAART. (C) 2001 Lippincott Willi ams & Wilkins.