Recommended safety requirements for the preparation of lepromin: a WHO Memorandum

The need for standardizing the preparation of lepromin and establishing safety requirements for it was recognized by the Scientific Working Group on the Immunology of Leprosy (IMMLEP) and its Steering Committee in 1978. It has now recommended the preparation of standard integral (Mitsuda-type) lepromin and, in collaboration with the WHO Biologicals unit, has drafted requirements for its preparation and testing. These direct that the source material should be Mycobacterium leprae from biopsy specimens of skin obtained from human (lepromatous) tissues or from the tissues of armadillos infected with M. leprae. The procedures to be followed for processing and testing the source material and for the preparation of lepromin from it are described. Requirements are laid down for the safety testing and labelling of the final product. In future, IMMLEP will consider supporting only those projects involving the use of lepromin prepared in accordance with these regulations.