Plasma levels of soluble CD27: a simple marker to monitor immune activation during potent antiretroviral therapy in HIV-1-infected subjects

Abstract

SUMMARYPlasma levels of soluble CD27 (sCD27) are elevated in diseases characterized by T cell activation and are used as a marker of immune activation. We assessed the usefulness of determining plasma sCD27 as a marker for monitoring immune activation in HIV-1-infected patients treated with highly active antiretroviral therapy (HAART). A first cross-sectional examination of 68 HIV-1-infected and 18 normal subjects showed high levels of sCD27 in HIV-1 infection; plasma sCD27 was correlated to HIV-1 viraemia and inversely correlated to CD4 + T cell count. Twenty-six HIV-1-infected patients undergoing HAART were studied at baseline and after 6, 12, 18 and 24 months of therapy. Seven additional patients under HAART were analysed at baseline, during and after interruption of therapy. In the total population, HAART induced a significant and progressive reduction, but not a normalization, of plasma levels of sCD27 after 24 months. A full normalization of plasma sCD27 was observed in the virological responders (undetectable HIV-1 RNA at months 18 and 24) and also in patients with moderate immunodeficiency at baseline (CD4 + T cell count >200 cells/mm 3 ). Changes in plasma neopterin paralleled the changes in sCD27 but only baseline sCD27 levels were predictive of a greater increase in CD4 + T cell count during the follow-up. Discontinuation of therapy resulted in a rapid increase of sCD27 plasma levels associated with viraemia rebound and drop in CD4 + T cell count. Our findings suggest that plasma sCD27 may represent an alternative and simple marker to monitor immune activation during potent antiretroviral therapy. HIV-1-induced immune activation can be normalized by HAART in successfully treated patients where the disease is not advanced.

CD27 Signaling Increases the Frequency of Regulatory T Cells and Promotes Tumor Growth

“…5E). This downregulation of CD27 may be due to shedding after ligation with CD70 (46). In accordance with this hypothesis, blocking CD70 in tumor-bearing BL/6 mice by FR70 resulted in an upregulation of CD27 expression on intratumoral CD25 þ Tregs, whereas the expression of CD27 on Tregs in the spleen remained unchanged ( Fig.…”

Dynamics of Memory B-Cell Populations in Blood, Lymph Nodes, and Bone Marrow during Antiretroviral Therapy and Envelope Boosting in Simian Immunodeficiency Virus SIVmac251-Infected Rhesus Macaques

“…Activated T, NK, and B cells all express cell surface CD27 (63), which can be proteolytically cleaved to produce a soluble form (sCD27). sCD27 levels are elevated in HIV-infected individuals (1,12,48) and correlate with plasma viremia (12) but can be decreased by successful HAART treatment over time. Further studies will be needed to determine the prevalence of CD27 Ϫ and CD27 ϩ PC/PB in healthy and immunodeficient hosts and whether they exhibit functional differences.…”

Altered expression of the receptor-ligand pair CXCR5/CXCL13 in B cells during chronic HIV-1 infection

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