ADHERENCE OF MYCOBACTERIUM-LEPRAE TO THE NASAL-MUCOSA IS INFLUENCED BY SURFACE INTEGRITY AND VIABILITY

The intranasal route is one of the main routes of Mycobacterium leprae infection and there is paucity of information regarding the mode of s pread of the pattern. The adherence of M. leprae to the nasal mucosa, its trapping within the sinuses of the head, and its fate after entry into the host was studied using mouse model. A comparison of the adher ence profile of M. leprae and Mycobacterium tuberculosis showed that w hile larger numbers of M. tuberculosis were demonstrated within lungs, greater numbers of M. leprae were present within the sinuses of the h ead. Adherence of M. leprae to the nasal mucosa was dependent on surfa ce integrity since opsonization and heat killing resulted in decreased numbers of M. leprae in the nasal sinuses and a greater amount enteri ng the lungs. The adherence appeared to the independent of the viabili ty of the bacilli, as similar numbers of formalin-fixed, rifampicin-tr eated and viable M, leprae entered the lungs in the initial stages. Ho wever the numbers of rifampicin-treated M. leprae in the nasal sinuses were 12-fold lower than the numbers of viable M. leprae. These result s indicated that both viability and surface integrity were important i n the entry of M. leprae and it's consequent dissemination.