Altered expression of CD88 and associated impairment of complement 5a-induced neutrophil responses in human immunodeficiency virus type 1-infected patients with and without pulmonary tuberculosis

The effect of infection with human immunodeficiency virus type 1 (HIV patient group), infection with Mycobacterium tuberculosis (TB patient group), and coinfection with both of these organisms (HIV/TB patient group) on the expression of CD88 on polymorphonuclear leukocytes (PMNL) was determined by using a receptor-specific monoclonal antibody and flow cytometry. A significant reduction in the fluorescence intensity of CD88 on PMNL was observed in the HIV and HIV/TB groups, compared with both the healthy donor (HD) and TB groups. Furthermore, when degranulation of PMNL was induced by ligation of CD88 by complement 5a (C5a), a large proportion of patients in the HIV and the HIV/TB groups was found to have reciprocal degranulation responses. Patients in the 2 HIV groups also were found to have significantly reduced C5a-induced chemotactic responses and significantly elevated peripheral levels of C5a des Arg, compared with the HD and TB groups. These differences may contribute to the increased susceptibility of HIV-1-infected individuals to secondary microbial infections.