In situ and in vitro characterization of the cellular immune response in erythema nodosum leprosum

• Published in: The Journal of immunology (1950) Vol. 136; no. 3; pp. 883 - 886
• Main Authors: Modlin, RL, Mehra, V, Jordan, R, Bloom, BR, Rea, TH
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Assoc Immnol 01.02.1986; American Association of Immunologists
• Subjects: Antibodies, Monoclonal; Antigens, Differentiation, T-Lymphocyte; Antigens, Surface - analysis; Antigens, Surface - immunology; Bacterial diseases; Biological and medical sciences; Erythema Nodosum - immunology; Human bacterial diseases; Humans; Immunity, Cellular - drug effects; Immunoenzyme Techniques; Infectious diseases; Interleukin-2 - analysis; Interleukin-2 - immunology; Lepromin - immunology; Leprosy; Leprosy - immunology; Medical sciences; Staining and Labeling; T-Lymphocytes, Regulatory - immunology; Tropical bacterial diseases; Tropical medicine; Tumor Necrosis Factor Receptor Superfamily, Member 7; Human; Skin disease; Antigenic determinant; Leprosy; Identification; Cellular immunity; Mycobacterial infection; Monoclonal antibody; Concanavalin A; In vitro; Infection; Immunology; Interleukin 2; T-Lymphocyte; Bacteriosis; Erythema nodosum leprosum; Biological receptor
• DOI: 10.4049/jimmunol.136.3.883
• ISSN: 0022-1767

We sought to evaluate cell-mediated immune responses in erythema nodosum leprosum (ENL), a reactional state occurring in lepromatous leprosy. Skin biopsies from patients with leprosy were studied with monoclonal antibodies against T lymphocyte antigenic determinants, interleukin 2 (IL 2), and IL 2 receptors (Tac) by using immunoperoxidase staining of frozen sections. Peripheral blood lymphocytes from 18 ENL patients were tested in vitro for lepromin-induced suppression of Con A stimulation. Serial studies of seven lepromatous patients who developed ENL during the course of the study showed increases in both the Leu-3a:Leu-2a ratio and the number of IL 2-positive cells. IL 2-positive cells comprised 0.3% of the cells in all of the ENL lesions studied as compared with the 0.03% found in nonreactional lepromatous lesions (P less than 0.001). Lepromin-induced suppression of the Con A response, present in nonreactional lepromatous patients, significantly decreased in patients developing the ENL reaction, but returned after recovery from ENL. These changes in tissues and peripheral blood suggest that the pathogenesis of ENL is related to cell-mediated immune processes. Despite these immunologic changes, however, ENL patients do not recover antigen-specific skin tests or eliminate Mycobacterium leprae.