ABSENCE OF A PROMINENT TH2 CYTOKINE RESPONSE IN HUMAN TUBERCULOSIS

Depressed Th1 responses are a prominent feature of human tuberculosis, but an enhanced Th2 response has not been detected in peripheral bloo d T cells stimulated in vitro with Mycobacterium tuberculosis. In dise ase due to Mycobacterium leprae, Th2 cells predominate in tissue lesio ns of patients with extensive disease but are absent from peripheral b lood, To determine if Th2 cells are present in tissue lesions of tuber culosis patients, we evaluated patterns of cytokine expression in lymp h nodes from tuberculosis patients with or without human immunodeficie ncy virus infection and in controls without tuberculosis, Gamma interf eron and interleukin-10 (IL-10) mRNA expression in tuberculosis patien ts with or without human immunodeficiency virus infection was high, wh ereas IL-4 expression in the same patients was low, Immunolabeling stu dies showed that macrophage production of IL-12 was increased in lymph nodes from tuberculosis patients, that gamma interferon was produced by T cells, and that IL-10 was produced by macrophages rather than Th2 cells, These results indicate that Th2 responses are not enhanced eit her systemically or at the site of disease in human tuberculosis.