Development of a mucosal challenge test for leprosy using leprosin A.

P Ramaprasad; I A Cree; M Oluwole; P D Samson

doi:10.1016/0022-1759(95)00219-7

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Development of a mucosal challenge test for leprosy using leprosin A.

P Ramaprasad·I A Cree·M Oluwole·P D Samson

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Abstract

There is little information about the mucosal immune response in leprosy. We have developed a nasal provocation test with leprosin A which will be used to investigate mucosal immunity to Mycobacterium leprae. Initial studies were performed with increasing doses of leprosin A (1.0 pg/ml-10 micrograms/ml) to determine the optimal safe dose of leprosin A. Anti-M. leprae IgA antibody and normal IgA concentrations were measured in the saliva of leprosy contacts and controls before and after instillation of leprosin A. Nasal leprosin A was well tolerated up to a concentration of 10 micrograms/ml without side effects. None of the six subjects who had not been exposed to leprosy had salivary IgA against whole M. leprae, whereas IgA was detected from 64 h to 140 h following instillation of leprosin A in all of the leprosy hospital workers and in 15 out of 18 healthy household contacts tested. There was no correlation between serum and salivary anti-M. leprae IgA levels before and after testing. Salivary IgA anti-lipoarabinomannan responses were seen in 12 out of 20 household contacts. Normal salivary IgA concentrations varied from 8 to 240 mg/l. The leprosin A nasal provocation test appears to be a safe method for the investigation of the role of mucosal immunity in the pathogenesis of leprosy.

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Adolescent Adult Antigens, Bacterial Enzyme-Linked Immunosorbent Assay Female Humans Immunoglobulin A Immunoglobulin A, Secretory Leprosy Male Middle Aged Mycobacterium leprae Nasal Mucosa Nasal Provocation Tests Saliva Tuberculin Journal Article

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P Ramaprasad, I A Cree, M Oluwole, P D Samson. 1995-12-27. Development of a mucosal challenge test for leprosy using leprosin A.. https://doi.org/10.1016/0022-1759(95)00219-7

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