Correlation of in vitro Fc receptor assay with in vivo mouse foot pad method

Resistant strains of M. leprae have been reported to the various antileprosy drugs. There is currently no accepted test to identify the susceptibility pattern of M. leprae to the drugs in a short period. The only accepted test is the mouse foot method which takes a long period to yield results. The Fc receptor assay using the ability of viable M. leprae to alter the membrane of the macrophage is well established. It takes only ten days and is inexpensive. In 6 cases of leprosy patients the susceptibility pattern was worked out both with the in vitro Fc receptor assay and the vivo in mouse foot method The results correlated very well leading to the fact that the assay system is reliable. Hence it can be used not only to study the status of a patient, but also to shortlist the number of compounds to be tested on the mouse foot pad as anti-leprosy drug candidates.