Leprosy-specific B-cells within cellular infiltrates in active leprosy lesions.
Leprosy is a spectral disease with polar lepromatous and tuberculoid forms correlating with enhanced humoral and cell-mediated immunity, respectively, against Mycobacterium leprae and the borderline forms, borderline lepromatous, midborderline, and borderline tuberculoid showing in-between clinical and immunological characteristics. Histopathologically, the cellular infiltrates of leprosy lesions show predominantly the presence of interacting T-cells and antigen presenting cells like macrophages, whereas the presence of B-cells has only been sporadically reported. The present study demonstrates by immunohistochemical techniques the presence of B-cells, including plasma cells, in active lesions from lepromatous leprosy, skin smear negative borderline lepromatous, and paucibacillary borderline tuberculoid leprosy. Furthermore, the study demonstrates the in situ production of M leprae-specific antibodies from BT lesions using an organotypic skin explant culture model. Finally, analysis of the cytokine release profile in supernatants of lesional organotypic skin cultures showed a microenvironment conducive to the differentiation and maturation of B-cells. The results demonstrate the presence of different functionally active B-cell stages within lesions of patients with leprosy, including borderline tuberculoid patients, which could secrete anti-M leprae-specific antibodies. However, their role in leprosy pathology remains to be elucidated.
Iyer
Anand M
AM
Department of Pathology, Academic Medical Center, Amsterdam 1105AZ, The Netherlands.
Mohanty
Keshar K
KK
Department of Immunology, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra 282001, India.
van Egmond
Danielle
D
Department of Pathology, Academic Medical Center, Amsterdam 1105AZ, The Netherlands.
Katoch
Kiran
K
Department of Internal Medicine, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra 282001, India.
Faber
William R
WR
Department of Dermatology, Academic Medical Center, 1105AZ Amsterdam, The Netherlands.
Das
Pranab K
PK
Department of Pathology, Academic Medical Center, Amsterdam 1105AZ, The Netherlands. Electronic address: p.k.das@amc.uva.nl.
Sengupta
Utpal
U
Department of Immunology, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra 282001, India.
D000907:Antibodies, Bacterial / Q000032:analysis; D000942:Antigens, Bacterial / Q000032:analysis; D015703:Antigens, CD / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D016207:Cytokines / Q000032:analysis; D006651:Histocytochemistry; D006801:Humans; D007918:Leprosy; D008264:Macrophages / Q000276:immunology; D009166:Mycobacterium leprae / Q000276:immunology; D012867:Skin / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D046509:Tissue Culture Techniques
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D015703:Antigens, CD; D016207:Cytokines