Changes of Soluble CD16 Levels in Serum of HIV-Infected Patients: Correlation with Clinical and Biologic Prognostic Factors

Abstract

The modulation of soluble CD16 titers in human immunodeficiency virus (HIV)-infected patients' serum, with an initial increase in Centers for Disease Control (CDC) clinical stage II and III patients followed by a dramatic drop in patients with AIDS (CDC clinical stage IV), is reported. These changes are statistically correlated with the CDC staging system, the number of CD4+ cells, the amount of p24 antigen in serum, and the anti-p24 antibody titers, indicating the potential value of soluble CD16 titer as an easily available serum marker of disease progression. To evaluate a possible link between this observation and the expression of membrane-associated CD16/FcRIII, flow cytometry immunofluorescence analysis was performed on peripheral blood lymphocytes from patients in three CDC stages; no specific changes in the number of natural killer cells expressing CD16+ antigens or in the total number of Leu19+ cells were found. However, there was a statistical correlation between the absolute number of T cells expressing CD16 antigens (CD3+/CD16+) and the modulated titers of soluble CD16 in HIV-infected serum.

Soluble CD16 Inhibits CR3 (CD11b/CD18)-Mediated Infection of Monocytes/Macrophages by Opsonized Primary R5 HIV-1

“…We found that sCD16 levels were greatly decreased in sera of patients as compared with healthy HIV-seronegative controls ( p ϭ 0.0001), confirming previous observations (33). The decrease in serum sCD16 levels was a surrogate marker for the progression of HIV disease.…”

“…Thus, it is conceivable that rsCD16, already proposed as a therapeutic agent for acute immune thrombocytopenic purpura (37) and multiple myeloma (33), may be introduced in the group of immunomodulatory drugs for HIV disease, through its ability to restrict the dissemination of HIV infection of CR3-expressing target cells.…”

Phenotypical and functional profiles of natural killer cells exhibiting matrix metalloproteinase-mediated CD16 cleavage after anti-HIV antibody-dependent activation

“…In addition to studies investigating alterations in NK cell phenotype during HIV infection, Fig. 4 soluble CD16 is detected in the sera of HIV-infected donors and correlates with disease progression [28]. This observation suggests that the activation-induced cleavage of CD16 may result in a serological marker that associates with HIV disease progression, further suggesting a linkage between chronic NK cell activation and HIV disease progression.…”

Ligand-engaged urokinase-type plasminogen activator receptor and activation of the CD11b/CD18 integrin inhibit late events of HIV expression in monocytic cells

“…[53][54][55] Of interest, another Mac-1 ligand, soluble CD16 (sCD16), was reported to be significantly decreased in HIV disease progression. 53,56 In addition, intercellular adhesion molecule-1, a ligand of Mac-1, is incorporated into the virion envelope. 57 A confounding aspect of the role of Mac-1 in HIV replication is the observation that ligation of the ␤ 2 integrin chain CD18 by immobilized Ab has been shown to increase HIV transcriptional activation in THP1 monocytic cells.…”