Levels of Soluble CD8 Antigen and Circulating Immune Complexes in Intravenous Drug Abusers: Relationships to HIV Antibody Serology

Abstract

A total of 36 intravenous drug abusers (IVDA) were studied for circulating immune complexes (CIC) and serum soluble CD8 antigen (sCD8). None had symptoms or signs of AIDS-related complex or AIDS. sCD8 levels were significantly higher in 18 patients who had HIV antibody (Ab) compared with 18 patients who were HIV Ab negative (1640 +/- 578 virus 804 +/- 264 U/ml, p less than 0.0001). In HIV Ab+ patients but not in HIV Ab- patients, sCD8 levels significantly correlated with percentages and absolute numbers of activated CD3+DR+ peripheral blood mononuclear cells (p = 0.0024 and 0.0183, respectively). Also in HIV Ab+ patients, CIC levels were significantly greater for both anti-C3 binding (13.1 +/- 11.1 versus 2.9 +/- 3.4 micrograms/ml, p = 0.002) and C1q binding (23.5 +/- 20.2 versus 6.3 +/- 4.3 micrograms/ml, p = 0.001) CIC. Serum C4 concentrations were lower in the HIV Ab+ patient group (33.9 +/- 10.1 versus 41.6 +/- 12.4 mg/dL, p = 0.043). In the seropositive group, IgG levels were higher (2206 +/- 859 versus 1615 +/- 645 mg/dl) and total CD4 cell counts were lower (757 +/- 344 versus 1172 +/- 402 cells per mm3), but at a less significant level (p = 0.024 and 0.005, respectively), than that seen for sCD8 and C1q CIC differences. These results suggest that elevations of both the lymphocyte activation marker sCD8 and antigen nonspecific CIC characterize earlier stages of HIV infection in IVDA.

Immunologic significance of increased soluble CD8/CD4 molecules in patients with active systemic lupus erythematosus

“…Moreover, we found no significant correlation in patients with Sjogren's syndrome (18). There are many reports of increased sCD8 molecules in HIV infected populations (27)(28)(29). An increased level of sCD8 has also been detected in patients with measles (30) and in patients with infectious mononucleosis (3 1).…”

Close Relationships between Neopterin and Beta-2-Microglobulin Levels in Intravenous Drug Abusers

“…In addition, we report the relationships between these two parameters and various previously reported [3][4][5] immunophénotypes (including H LA-DR + CD3 + cells) and soluble CDS antigen concentrations. At the present time, it is not known whether certain immune activation markers related to clinical progression are independent or are interdependent.…”

“…Aliquots of serum stored at -70°C were used for all serological studies. Assessments of soluble CDS antigen ('Soluble T8'; T Cell Sciences, Cambridge, Mass., USA) and circu lating immune complex ('CIC' and 'Raji-CIC'; Cytotech, San Diego, Calif.) concentrations were performed using commercial enzyme-linked immunosorbent assay kits, and the results have been previously reported [4,5).…”

“…We have previously reported that the expression of DR on peripheral blood T lympho cytes is significantly higher in HIV antibody positive than in HIV antibody negative IVDA and that this difference of activated T cells is more significant than the difference in the helper cell concentrations in the two groups [3]. More recently, we reported the rela tionships between circulating soluble CD8 antigen concentrations and various immunophénotypes in this same population of IVDA [4,5].…”