The effect of chlamydia trachomatis and inflammatory leukocytes on hf/-1 replication in vitro

Objectives: Epidemiological studies have shown that Chlamydia trachomatis (CT) infection is a risk factor for HIV acquisition. Polymorphonuclear leukocytes (PMNs) and mononuclear cells (PBMCs) are found in the female genital tract in response to CT infection. We studied the effects of CT extracts and inflammatory leukocytes on HIV-1 replication in vitro. Study Design: Chronically HIV-1 infected monocytic cells (Ul) were incubated with CT (human E strain) extract, PMNs, or PBMCs. HIV replication was determined by p24 antigen measurement at 24, 48, 72. and 96 hours. Results: After 96 hours of incubation HIV replication was increased 25 fold with PBMC coincubation {p<0.01), 48 fold with PMN coincubation (p<0.01). 27 fold with CT extract and PBMC coincubation (p<O.OI), and 33 fold with CT extract and PMN coincubation. Table i shows data for 24, 48, 72, and 96 hours: Conclusion: Inflammatory cells found in the female genital tract, in association with CT infection, significantly enhance HIV replication in vitro. CT alone or in combination with inflammatory cells did not further enhance HIV replication. This data suggests that the inflammatory response to CT infection is in part responsible for increased risk of HIV acquisition. Further studies are needed to elucidate this complex interaction.