Journal Article

Immunohistochemical characterization of the M4 macrophage population in leprosy skin lesions

Quaresma, Juarez Antonio Simões, de Sousa, Jorge Rodrigues, Lucena Neto, Francisco Dias, Sotto, Mirian Nacagami

2018

Overview

Background Since macrophages are one of the major cell types involved in the Mycobacterium leprae immune response, roles of the M1 and M2 macrophage subpopulations have been well defined. However, the role of M4 macrophages in leprosy or other infectious diseases caused by mycobacteria has not yet been clearly characterized. This study aimed to investigate the presence and potential role of M4 macrophages in the immunopathology of leprosy. Methods We analyzed the presence of M4 macrophage markers (CD68, MRP8, MMP7, IL-6, and TNF-α) in 33 leprosy skin lesion samples from 18 patients with tuberculoid leprosy and 15 with lepromatous leprosy by immunohistochemistry. Results The M4 phenotype was more strongly expressed in patients with the lepromatous form of the disease, indicating that this subpopulation is less effective in the elimination of the bacillus and consequently is associated with the evolution to one of the multibacillary clinical forms of infection. Conclusion M4 macrophages are one of the cell types involved in the microbial response to M. leprae and probably are less effective in controlling bacillus replication, contributing to the evolution to the lepromatous form of the disease.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adult / Atherosclerosis / Biomarkers - metabolism / Brazil / Cytokines / Disease / Evolution / Female / Growth factors / Humans / Immune response / Immune system / Immunohistochemistry / Immunology / Infections / Infectious Diseases / Interleukin 6 / Internal Medicine / Leprosy / Leprosy - immunology / Leprosy - metabolism / Leprosy - pathology / Leprosy, Lepromatous - immunology / Leprosy, Lepromatous - metabolism / Leprosy, Lepromatous - pathology / Leprosy, Tuberculoid - immunology / Leprosy, Tuberculoid - metabolism / Leprosy, Tuberculoid - pathology / Lesions / Lipids / Macrophage / Macrophages / Macrophages - immunology / Macrophages - metabolism / Macrophages - pathology / Male / Matrilysin / Medical Microbiology / Medicine / Medicine & Public Health / Microorganisms / Mycobacteria / Mycobacterium leprae - immunology / Parasitology / Patients / Phenotypes / Research Article / Skin - immunology / Skin - metabolism / Skin - pathology / Skin diseases / Skin Diseases - immunology / Skin Diseases - metabolism / Skin Diseases - microbiology / Skin Diseases - pathology / Subpopulations / Tropical Medicine / Tuberculosis and other mycobacterial diseases / Tumor necrosis factor-TNF / Tumor necrosis factor-α