J Korean Soc Microbiol.  1997 Jun;32(3):357-368.

Requirements for the Differentiation of CD4+ Cytotoxic T cells Specific to Mycobacterial Antigens

• Cha CY
• Lim DG
• Kim JM
• Kwak SJ

Abstract

The cytolytic activity of CD4' T cells, both human and murine, has been clearly demonstrated in the immune response to mycobacterial infection and suggested to play a significant role in the protection and immunopathology. However, Uttle is known about the differentiation of CD4' CTL. In order to address this issue, we examined the influences of some factors on the generation of CD4' CTL specific to mycobacterial antigens. After 7 days' stimulation of PBMCs from healthy tuberculin reactors with mycobacterial antigens, the cytolytic activity of purised CD4' T cells toward autologous macrophages infected with mycobacteria was measured by Cr release assay. First, we found that both of live M. tubeiculosis and soluble antigens (ST-CF) induced the cytolytic activity of CD4' T cells, although the inducibility of the former was slightly greater than the latter. Second, the cytolytic activity was maximally induced at the relatively low antigen concentration (0.2:1 bacteria:monocyte ratio or 0.5 mg/ml of ST-CF). Finally, in the presence of increasing amounts of neutralizing anti-IL-12 or anti-IFN-r MoAb, the cytolytic activity of CD4+ T cells was decreased in a dose-dependent manner. These results suggest that low dose of antigen, its particulate type give mycobacteria), IL-12, and IFN-r give some positive signals for the generation of CD4+ CTL.

MeSH Terms

Humans
Interleukin-12
Macrophages
T-Lymphocytes*
Tuberculin
Interleukin-12
Tuberculin