IL-4 in TB

Dr. Huang-Pin WuDiv. Pul. Med., Dep. Int. Med., Chang

Gung Memorial Hospital, Keelung

CD 30 surface antigen

Distribution Macrophage Activated T, B, NK cells

Function T cell receptor-mediated cell death Activates NfB

Increased apoptotic cell % along with increased CD30+ cells

J Immunol 2001;167:1230

IL-4 might contribute to the apoptosis of M. tuberculosis–activated T lymphocyte

J Immunol 2001;167:1230

Anti-IL-4 inhibit elevation of CD30+ cell %

IL-4 enhanced macrophage endocytosis by activationof phosphatidylinositol 3-kinase

J Immunol 1999;162:4606.

IL-4 could inhibit the extracellular killing function of activated IFN-gamma induced macrophages.

J Immunol 1992;148:3578.

Conclusion

IL-4 was still important in macrophage function.

Patients with a high degree of IL-4 response might have attenuated macrophage activity, thus reducing their ability to fight M. tuberculosis.

IL-42

The second of the four exons in the alternative splice variant of IL-4 mRNA is omitted.

Regulation of human IL-4 activity

IL-42 IL-4

A higher ratio of IL-42 to IL-4 in latent tuberculosis patients compared with that in controls

Immunology 2004;112:669.

Tuberculosis patients expressed higher IL-42 mRNA than did controls

J Infect Dis 2000;181:385.

Patients with greater IL-42 expression had more extensive disease

J Infect Dis 2000;181:385.

Question

The capability for IL-4 and IL-42 production in T cells of tuberculosis patients ?

The relationship of chest radiographic patterns and IL-4 production capability ?

Conclusion The ratio of IL-42 to IL-4 was a key factor a

ssociated with disease severity in patients with active pulmonary tuberculosis.

The inefficient expression of IL-4 and IL-42 mRNA in stimulated PMBCs of patients with pulmonary infection.

IL-4 may play a similar role in pulmonary infection, either M. tuberculosis or nontubercular bacillus.