Transforming growth factor β and apoptosis in leprosy skin lesions: possible relationship with the control of the tissue immune response in the Mycobacterium leprae infection

The course of leprosy depends of the host immune response which ranges from the lepromatous pole (LL) to the tuberculoid pole (TT). A comparative study was conducted in 60 patients with the LL and TT. The results showed a mean expression of TGF-β of 339 ± 99.4 cells/field for TT and of 519.2 ± 68.2 cells/field for LL. Frequency of apoptosis was 6.3 ± 1.8 in TT and 14.0 ± 6.1 in LL. A correlation (p = 0.0251) between TGF-β and caspase-3 in the LL was found. This finding indicates a role of TGF-β and apoptosis in the immune response in leprosy.