Behaviour of macrophages to Mycobacterium leprae. A tissue culture study

Macrophage culture was performed on 45 healthy adults who were initially categorised on the basis of their Lepromin reactivity using Dharmendra antigen. There were 25 individuals in the Lepromin positive group and 20 in the Lepromin negative group. The cultures were challenged with M. leprae and the macrophages studied at varying time intervals of culture. No difference was evident in the behaviour of cultured macrophages to M. leprae in both the groups. The Lepra bacilli were phagocytosed by the macrophages and retained essentially intact till the termination of culture. The Lepromin reactivity of a healthy individual was not reflected on the macrophage function in vitro. The observations suggested against the possibility of an intrinsic genetically determined macrophage defect in dealing with M. leprae.