Growth of Mycobacterium leprae in a redox system: III. Evidence of growth at low temperature (psychrophilia) and, further refinement of growth medium.

Considerable growth enhancement, largely as non-acid fast, slender and long rods has been seen when incubated at 10 degrees C. Concentration of some of the media constituents have been reduced that has improved the quantum of growth. A remarkable proneness to physical disintegration of the grown bacilli has been seen and its significance discussed. Also, the possible immunogenic advantage of non-AF M. leprae has been discussed. The question of identification is still not solved, and work is in progress.

Growth of Mycobacterium leprae in a redox system: II. Further improvements in the system and growth efficiency.

Improvement of the Redox System for growth of M. leprae as brought about by modification in the concentration and mode of preparation of individual media constituents, and by addition of newer substances, is being reported. A structural modification in the construction of the Thunberg's tubes and flasks that are used as culture vessels, has been introduced for ease of handling. Vitamin E (alpha-tocopherol) has been found to be useful. Concentrations of Liposomes and Gelatin in the medium could be reduced by at least five folds, considerably easing thereby smearing and harvesting of cultures. Dimercaptopropanol British Anti-lewisite or BAL) has been used, but its usefulness or otherwise is yet to be determined conclusively. The basis of intracellular parasitism of M. leprae has been discussed.