Assessment of Dharmendra antigen. II. Standardisation of the antigens

Dharmendra antigen with different bacterial counts (16, 12.5, 10, 7.5, 5 and 2.5 million/ml) have been utilized for determination of skin delayed hypersensitivity in leprosy patients. It has been noted that antigen with 10 million acid fast bacilli (AFB)/ml mounts a standard early (24 hrs) as well as late (3 weeks) reaction in patients. Lepromatous patients do not show any skin reaction with this dilution. Thus, a standard Dharmendra antigen has been prepared using a considerably smaller number of organisms as compared to the International standards for Mitsuda antigen.