Studies on the immunology and serology of Leishmaniasis V. The use of particles as vehicles in passive agglutination tests

Abstract

Naked sheep erythrocytes, tanned sheep erythrocytes, tanned human erythrocytes of Group O, tanned and formolized sheep erythrocytes and latex particles were sensitized with antigens derived from 8 strains of Leishmania spp. and used in agglutination tests with various antisera and immune sera. Sensitized formolized erythrocytes were used in agglutination tests. Successful agglutination tests could be performed consistently with any of these particles provided formalin treatment was omitted. Prior treatment with formalin rendered erythrocytes difficult to sensitize. Formalin treatment of sensitized erythrocytes caused auto-agglutination. The tests with various sera and various absorbed sera revealed serological differences between the strains used. A strain of Leishmania from Panama quite distinct from L. mexicana of British Honduras and L. braziliensis of Brazil is distinct from 2 strains of Leighmania from Costa Rica. The 2 Costa Rican strains represented distinct serotypes. Serological differences were detected between L. donovani from India and L. donovani from Kenya. No serological difference was detected between L. donovani (post-kala-azar dermal leishmanoid) from India and L. tropica from Israel or between L. braziliensis of Brazil and 1 strain of L. pifanoi from Brazil.