Current Concepts in the Immunology of Leprosy

This the nonleprologist with current immunologic concepts of leprosy and with the data that support these concepts. For further reading, the reviews by Rees,¹Wager,²Turk and Bryceson,³Bullock,⁴Skinsnes,⁵Convit and Ulrich,⁶and a memoranda sponsored by the World Health Organization⁷are recommended. CLASSIFICATION Rabello's polar concept of leprosy⁸,⁹and the studies of Ridley and co-workers,¹⁰⁻¹²which were based on clinical and histological observations, have been pivotal in the formation of current ideas concerning immunologic mechanisms in the pathogenesis of leprosy. Ridley and co-workers¹⁰⁻¹²have provided nomenclature, in the form of a system of diagnostic classification, that is fundamental to most current immunological investigations. For those readers who are not conversant with the classification of leprosy, two analogies may be helpful. Leprosy is likened to a salami that can be taken as a whole or sliced, either thickly or