LACK OF T-LYMPHOCYTOSIS AND POOR INTERFERON-GAMMA PRODUCTION IN BAL FLUID FROM HIV-NEGATIVE IMMUNOCOMPETENT PATIENTS WITH PULMONARY NONTUBERCULOUS MYCOBACTERIOSIS

Very little is known about the pathogenesis of pulmonary non-tuberculo us mycobacteriosis in immunocompent individuals. Local inflammatory re sponse was assessed by examining bronchoalveolar lavage fluid from 13 HIV-negative patients (12 F) without known cell-mediated immunosuppres sion, aged 48-72 y (median age 60 y), with non-tuberculous lung mycoba cteriosis. Macrophages, lymphocytes, polymorphonuclear neutrophils and eosinophils in bronchoalveolar lavage fluid were analysed morphologic ally, and the subsets of T-lymphocytes (CD3(+), CD4(+), CD8(+)), HLA-D R+, B-lymphocytes (CD19(+)) and CD16(+)/CD56(+) cells (natural killer, NLC cells) were analysed by flow cytometry. Interleukin-l beta (IL-1 beta), IL-2, IL-4, IL-6, IL-8, IL-10 and interferon-gamma (IFN-gamma) levels were assessed by ELISA. The total number of cells/ml was signif icantly higher in BAL fluid from the patients (median value=880 x 10(3 )/ml) compared to six healthy controls (200 x 10(3)/ml). The polymorph onuclear neutrophil population was significantly increased in the pati ents both proportionally and in the count/ml. The proportion of macrop hages was significantly reduced in the patients but not the count/ml. The count of lymphocytes/ml was significantly higher in the patients b ut the proportion of lymphocytes was unchanged. No significant differe nce was seen in the relative proportion of NK cells, B- or T-lymphocyt es and HLA-DR+ compared to the healthy controls. The IL-1 beta and IL- 8 levels were significantly increased in the patients. No differences were seen between the patients and controls in the leukocyte or lympho cyte subsets in peripheral blood. The focal inflammatory response in B AL fluid from the studied patients was characterized by granulocytosis , and increase in the IL-1 beta and IL-8 levels. There was no specific T-cell response.