A Study on the Biochemical Characteristics of Lepromin Antigen / 대한피부과학회지

ABSTRACT

It is generally accepted that tbe lepromin test is of great value in the type classification and the evaluation of the prognosis of leprosy. But the nature of the antigenicity in lepromin reaction stiIl remains uncertain. The present study was carried out to investigate the antigenic characteriatics of the early(Fernandez) and the late (Mitsuda) reactions to Mitsuda lepromin antigen. Mycobacterium leprae was purified by trypsin digestion from human lepromas, and was broken down by passing 5 times through a French Pressor at 16, 000 p.s.i.. From the broken cell suspension, cell wall, cytoplasm, very low density lipoprotein (VLDL) and lipopolysaccharide (LPS) were prepared. IntradermaI skin tests were perforrned on 30 leprosy patients classified according to the Ridley-Jopling scale (4 TT, 6 BT, 2 BB, 7 BL and 11 LL), with 0. 1ml of the Mitsuda lepromin(intact cells) broken cells, cell wall, cytoplasm, VLDL and LPS antigens. Readings for the early and the late reactions were done 72 hours and 28 days, respectively, after itradermal injections of the above antigens. The results are summerized as follows 1, Early reactions were elicited by broken cells, cell wall and cytoplasm in all of the patients who could react to Mitsuda lepromin antigen. VLDL and LPS antigens could also elicit early reactions in 9(56)% and in 14(88%), respectively, of the 10 patients who showed positive reaction to Mitsuda lepromin antigen. These results mean that the early reaction may be due to multiple antigena, originated either from M. leprae or from contaminated human tissues. 2. Late reactions were elicited by broken cells and cell wall antigens, but not by cytoplasm antigen, in all of the patients who showed late reactions to Mitsuda lepromin antigen. These results mean that broken cells also produce a late reaction and the specific antigen(s) of the late reaction may reside in the cell wall fraction of the M. leprae.