Detection of microbial antigenic components of circulating immune complexes in HIV patients: Involvement in CD4 + T lymphocyte count depletion

Abstract

Objective To investigate the prevalence of microbial antigenic components of circulating immune complexes amongst grades of CD4 T lymphocyte counts in HIV sero positive and sero-negative participants. Methods Polyethelene glycol (PEG-600) and buffering methods of precipitation and dissociation of immune complexes was used to generate immune solution from sera of 100 HIV sero-positive and 100 HIV sero-negative participants. These were categorized into 3 grades based on CD4 count: > 500 cell/mm 3, 200-499 cell/mm 3 and <200 cell/mm 3. The immune solutions were assayed using membrane based immunoassay and antibody titration, along side its unprocessed serum for detection of various microbial antigens and or antibodies. CD4 T cell counts were estimated using Patec Cyflow SL-3 Germany. Results Antigenic component of immune complexes of various infectious agents was detected in 99 and 70 HIV sero-positive and HIV sero-negative participants, respectively. In group A, there were 10 HIV positive participants, including 4 (40.0%) had circulating immune complexes(CIC s) due to Salmonella species only; 1(10.0%) due to Salmonella-Plasmodium falciparum (P. falciparum), Salmonella-P. falciparum-HCV and P. falciparum antigens, respectively. In group B, 45(45.4%) HIV sero-positive participants with CIC s had CD4 T lymphocyte count between 200-499 cells/mm 3. Out of these, 20(44.4%) had CIC s due to Salmonella species only; 9(20%) due to Salmonella-P. falciparum. In group C, there were 44(44.4%) HIV sero-positive participants, including 3(6.8%) due to Salmonella species only; 24(54.4%) due to Salmonella-P. falciparum; 2(4.5%) due to P. falciparum only. Conclusions In HIV sero-positive participants, presence of heterogeneity of Salmonella species- P. falciparum antigens was highly incriminated in CD4 count depletion but not homogeneity of malaria parasites antigens. Malaria parasites antigens only were incriminated in CD4 + count depletion amongst HIV sero-negative participants. Before taking any decision on the management of HIV-1-positive individuals, their malaria and Salmonella paratyphi status should be assessed, but not malaria status alone.