Isolation and identification of a substance from serum of leprosy patients
To The Editor:
Sera from healthy persons and leprosy patients (5320 sera) who had various forms of the disease were examined using the reaction of Rubino (1-6). Sera from some patients which gave a positive reaction were selected and submitted to fractionation on a Sephadex column. A fraction containing agglutination activity for sheep erythrocytes was isolated. This activity was evident only after the fractionation procedure. The active fraction was immediately concentrated and lyophilized. In order to observe a positive reaction of agglutination, it was necessary to use recently prepared erythrocytes. The isolated substance had a molecular weight of 76 kDa (7), an isoelectric point (8) of 5.70, and has high activity in causing the agglutination of sheep erythrocytes. The chemical structure is being determined (9).
- E. Garcia Lima
Associate Professor of Immunology
- C. J. Laura
Associate Professor of Biochemistry
Faculdade de Medicina de Ribeirao Preto
Universidade de Sao Paulo
14.049 Ribeirão Preto, S.P., Brasil
REFERENCES
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