Characterization of a circulating antigen involved in immune complexes in visceral leishmaniasis patients

• Published in: The American journal of tropical medicine and hygiene Vol. 49; no. 4; p. 492
• Main Authors: Mary, C, Ange, G, Dunan, S, Lamouroux, D, Quilici, M
• Format: Journal Article
• Language: English
• Published: United States 01.10.1993
• Subjects: Animals; Antibodies, Monoclonal - immunology; Antibody Specificity; Antigen-Antibody Complex - blood; Antigen-Antibody Complex - chemistry; Antigen-Antibody Complex - immunology; Antigens, Protozoan - biosynthesis; Antigens, Protozoan - blood; Antigens, Protozoan - chemistry; Antigens, Protozoan - immunology; Blotting, Western; Dogs; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Humans; Kinetics; Leishmania infantum - immunology; Leishmaniasis, Visceral - blood; Leishmaniasis, Visceral - immunology; Microscopy, Fluorescence; Molecular Weight
• ISSN: 0002-9637
• DOI: 10.4269/ajtmh.1993.49.492

Complications of visceral leishmaniasis are explained in part by immune complex pathology, particularly nephritis. Using the polyethylene glycol precipitation method, we identified among these complexes a Leishmania infantum circulating antigen by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. Monoclonal antibodies were produced to specifically detect this antigen. This protein (molecular weight 51 kD) is a cytoplasmic antigen of L. infantum and its synthesis by promastigotes is related to stationary-phase culture. It was present in sera from dogs whose leishmaniasis was associated with nephritis, and it was found in the sera of 30% of human patients with visceral leishmaniasis. It was also detected in the sera of patients with cutaneous leishmaniasis, and it persists in the sera of clinically cured subjects.