Widespread use of BCG has not controlled tuberculosis, and more effective vaccines are clearly needed. Although chemotherapy will remain the mainstay of antituberculosis treatment, the use of adjunctive immunotherapeutic modalitites is attractive, par...
Widespread use of BCG has not controlled tuberculosis, and more effective vaccines are clearly needed. Although chemotherapy will remain the mainstay of antituberculosis treatment, the use of adjunctive immunotherapeutic modalitites is attractive, particularly in persons with drug-resistant tuberculosis. Administration of IL-2 or IFN-γto tuberculosis patients enhance bacillary elimination.
Cell-mediated immunity is the critical protective immune response in tuberculosis. Mycobacterial antigens are recognized by T cells and that elicit production of protective cytokines are potentially important vaccine antigens. The 30 kDa antigen is secreted in large quantities by growing mycobacteria. That antigen elicits greater proliferation in lymphocytes from healthy tuberculin reactors than healthy tuberculin nonreactors.
In this study, the T lymphocyte proliferative responses to 30 kDa antigen from Mycobactrium tuberculosis H37Rv were examined by using tonsilar and peripheral blood lymphocytes from PPD(+) and PPD(-) tonsilectomized persons. When cultured with 30 kD antigen, tonsilar mononuclear leukocytes and T cells of PPD(+) demonstrated more ^3H-thymidine incorporation than PPD(-) persons (stimulation index was 2.5 and 1.9, 0.8 and 1.0, repectively). Peripheral blood mononuclear cells (PBMC) and peripheral blood T lymphocytes were shown the similar responses to this antigen. The combination of IL-2 and 30 kDa antigen elicited a significant proliferative responsiveness in tonsilar mononuclear leukocytes and T cells of PPD(+) persons (SI was 20 and 14.1). PBMC and peripheral blood T cells of PPD(+) persons were also shown a significant responsiveness, but PPD(-) persons did not show.
These results demonstrate that the 30 kDa antigen and IL-2 have a synergistic stimulatory property in mycobacteria sensitizing lymphocytes.