Changes in circulating levels of soluble cell adhesion molecules followinghighly active antiretroviral treatment of HIV-1-infected patients

Increased levels of soluble cell adhesion molecules (sCAM) have been report ed in HIV-1 infection and may possibly contribute to altering the adhesion mechanisms of phagocytic cells. We evaluated the effect of highly active an tiretroviral therapy (HAART) on plasma levels of sl-selectin, sE-selectin, intercellular cell adhesion molecule-1 (sICAM-1), sICAM-3, and vascular cel l adhesion molecule-1 (sVCAM-1). Study participants included 22 HIV-1-infec ted patients with a CD4(+) T-cell count/mu l below 500 who were started on a HAART regimen and followed up for 9 months. After the initiation of thera py, plasma sl-selectin concentrations progressively decreased to normal ran ges in the majority of our patients (P < 0.001), while no changes in sE-sel ectin were found. In all patients sICAM-1 remained relatively constant at s ignificantly elevated concentrations during the 9 months of therapy. A sign ificant reduction in plasma concentrations of both sICAM-3 and sVCAM-1 was found; however, the levels of these sCAM were not normalized by HAART and r emained significantly elevated throughout the study (P < 0.001). The reduce d release of sL-selectin could improve the ability of phagocitic cells to m igrate in response to chemotactic stimuli after starting HAART. On the othe r hand, the persistent elevation of sICAM-1, sICAM-3, and sVCAM-1 could ref lect continuous HIV-1-mediated immune activation, despite adequate control of plasma HIV-1 replication by therapy. (C) 2000 Academic Press.