Loss of CD127 & increased immunosenescence of T cell subsets in HIV infected individuals.

Background & objectives: HIV infection is characterized by a perturbation in T cell homeostasis, leading to alteration in T cell subsets. In addition to alteration in differentiation, HIV infection also leads to change in T cell survival and regenerative capacity, as suggested by differential expression of CD127 and CD57. We evaluated the expression patterns of CD127 and CD57 on CD4 and CD8 effector, memory and naïve T cell subsets in HIV-infected and uninfected individuals. Methods: We characterized T cell subsets based on expression of these markers, and compared their expression pattern in HIV infected subjects and uninfected controls. We further assessed therapy generated changes in these subsets and expression of CD127 and CD57 on them. Results: There was a generalized decrease in naïve CD4 and CD8 T cells in HIV infected subjects. These changes in T cell subset distribution were related to antigen load. CD127 expression was significantly reduced in T cells from HIV infected subject. In association to this, HIV infected subjects had higher percentage of T cell subsets expressing CD57. Increased CD57 and reduced CD127 expression correlated with plasma viraemia and CD8 T cell activation state. Incomplete restoration of T cell subset proportions was observed, despite suppression of viral replication and increase in CD4 T cell counts. Further, the improvement was more pronounced in CD127 expression. Interpretation & conclusions: HIV infected subjects have reduced T cell regenerative capacity along with increased senescence, highlighting decreased proliferation and effector activities.

Usefulness of hemoglobin and albumin as prognostic markers for highly active antiretroviral therapy for HIV-1 infection.

Background: Usefulness of hemoglobin and albumin as prognostic markers for highly active anti-retroviral therapy for HIV-1 infection. Introduction: Anemia and hypoalbuminemia are common complications in human immunodeficiency virus (HIV) infection. We aimed to investigate the changes in hemoglobin and albumin levels in response to highly active antiretroviral therapy (HAART). Further, we evaluated the appropriateness of using hemoglobin and albumin as HIV disease progression markers. Materials and Methods: A prospective longitudinal study of 122 subjects was carried out. Pre-treatment, one year, and two year post-treatment hemoglobin, and albumin levels were correlated with respective CD4+ T cell counts. The sensitivity, specificity, and positive predictive value of each marker against CD4+ T cell counts were calculated in order to establish the appropriateness of use of these parameters as surrogate disease progression and prognostic markers. Results: Mean hemoglobin and albumin levels pre-, one, and two year post HAART were 9.7 g/dL, 12.1 g/dL, and 13.1 g/dL, respectively, P = 0.001; albumin: 3.7 gm%, 4.4 gm%, and 4.7 gm%, respectively, P = 0.001. There was a positive correlation between hemoglobin, albumin, and CD4+ T cell count at pre-treatment, one year, and two year post-treatment visit. Both albumin and hemoglobin had high sensitivity when compared to CD4+ T cell counts. Conclusions: Hemoglobin and albumin levels were found to increase after initiation of HAART. Hemoglobin and albumin were seen to be a strong prognostic marker of HIV disease progression at pre-, one, and two year post-treatment. Therefore, hemoglobin and albumin may be used together along with CD4 + T cell counts in HIV management, particularly in resource-poor settings.