Preliminary immunological studies in search of correlates of protective immunity carried out on some Iranian leprosy patients and their families

Abstract

Multiple skin-testing, lymphocyte transformation tests and enzyme-linked immunosorbent assay of antibodies to mycobacterial antigens have been carried out on patients and their healthy children living in Baba Baghi Leprosy Sanatorium in Iran. The data reported shows a remarkable correlation between responses to Mycobacterium leprae and M. vaccae in all 3 test systems. The percentage of positive responders to skin tests with Leprosin A amongst the children is higher than has previously been found and BCG has been shown to enhance the capacity of the individual to recognize M. leprae in this way. Finally, the majority of a small number of children considered to be protected from leprosy have been shown to possess lymphocytes that transform in the presence of M. leprae and M. vaccae antigens, but little antibody to M. leprae by the enzyme-linked immunosorbent assay. Of the 3 types of test assessed here only skin-testing appears to be of any value as a measure of protection, but whether even this will prove useful at the individual level is far from certain.