[HTML][HTML] HIV-infected individuals with low CD4/CD8 ratio despite effective antiretroviral therapy exhibit altered T cell subsets, heightened CD8+ T cell activation, and …

S Serrano-Villar, T Sainz, SA Lee, PW Hunt… - PLoS …, 2014 - journals.plos.org
S Serrano-Villar, T Sainz, SA Lee, PW Hunt, E Sinclair, BL Shacklett, AL Ferre, TL Hayes…
PLoS pathogens, 2014journals.plos.org
A low CD4/CD8 ratio in elderly HIV-uninfected adults is associated with increased morbidity
and mortality. A subset of HIV-infected adults receiving effective antiretroviral therapy (ART)
fails to normalize this ratio, even after they achieve normal CD4+ T cell counts. The
immunologic and clinical characteristics of this clinical phenotype remain undefined. Using
data from four distinct clinical cohorts and three clinical trials, we show that a low CD4/CD8
ratio in HIV-infected adults during otherwise effective ART (after CD4 count recovery above …
A low CD4/CD8 ratio in elderly HIV-uninfected adults is associated with increased morbidity and mortality. A subset of HIV-infected adults receiving effective antiretroviral therapy (ART) fails to normalize this ratio, even after they achieve normal CD4+ T cell counts. The immunologic and clinical characteristics of this clinical phenotype remain undefined. Using data from four distinct clinical cohorts and three clinical trials, we show that a low CD4/CD8 ratio in HIV-infected adults during otherwise effective ART (after CD4 count recovery above 500 cells/mm3) is associated with a number of immunological abnormalities, including a skewed T cell phenotype from naïve toward terminally differentiated CD8+ T cells, higher levels of CD8+ T cell activation (HLADR+CD38+) and senescence (CD28− and CD57+CD28−), and higher kynurenine/tryptophan ratio. Changes in the peripheral CD4/CD8 ratio are also reflective of changes in gut mucosa, but not in lymph nodes. In a longitudinal study, individuals who initiated ART within six months of infection had greater CD4/CD8 ratio increase compared to later initiators (>2 years). After controlling for age, gender, ART duration, nadir and CD4 count, the CD4/CD8 ratio predicted increased risk of morbidity and mortality. Hence, a persistently low CD4/CD8 ratio during otherwise effective ART is associated with increased innate and adaptive immune activation, an immunosenescent phenotype, and higher risk of morbidity/mortality. This ratio may prove useful in monitoring response to ART and could identify a unique subset of individuals needed of novel therapeutic interventions.
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