Detection of HIV-1 provirus in bronchoalveolar lavage cells by polymerase chain reaction

This study was undertaken to evaluate whether HIV-seropositive individuals harbor HIV provirus in cells obtained by bronchoalveolar lavage (BAL). BAL cells were obtained from 14 HIV-positive patients undergoing bronchoscopy for evaluation of acute pulmonary symptoms. Cells were fractionated into macrophage-enriched and lymphocyte-enriched populations. The quantity of HIV-1 proviral DNA in the unfractionated BAL cells and in each population of fractionated cells was determined following polymerase chain reaction (PCR) amplification. Detectable quantities (3-90 copies/100,000 cells) of HIV-1 proviral DNA were found in unfractionated BAL cells in 12 of 14 patients. In the other two patients, provirus was detected after a sevenfold enrichment of lymphocytes. Provirus was also detected in BAL macrophages from 8/14 patients although proviral content was significantly higher in the lymphocyte fraction (133 +/- 72 vs. 35 +/- 22 proviral copies, p = 0.03). No correlation was seen with the ability to detect provirus in lymphocyte- or macrophage-enriched fractions and clinical diagnosis (e.g., Pneumocystis carinii pneumonia). The data suggest that lymphocytes are the predominant cells that contain provirus found in the lungs, although macrophages may be infected in some patients.