title: Intracellular localization of myeloperoxidase in murine peritoneal B-lymphocytes and macrophages.
abstract: Generation of hypochlorous acid (HOCl), an important microbicidal agent, is considered to be the main function of myeloperoxidase (MPO), an enzyme present in phagocytes. High amounts of MPO are present in neutrophil azurophilic granules, which are mobilized into the phagolysosome vacuole during phagocytosis. MPO is also present in monocytes and macrophages, although to a lesser degree than in neutrophils. In the present study, we investigated the distribution of MPO in murine peritoneal cells using flow cytometry, confocal microscopy (CM) and transmission electron microscopy (TEM). MPO was observed in macrophages, and surprisingly, we detected MPO in B lymphocytes, specifically in B1-a. MPO was present in cytoplasmic granules, vesicles, mitochondria and the nucleus of murine peritoneal cells. Together, these findings suggest that, in addition to its known microbicidal activity, MPO has a myriad of other unanticipated cellular functions.
authors: Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Alfenas, MG 37130, Brazil.
authors: Tomaz Henrique
authors: TH
authors: de Araujo
authors: Sabrina Sayori
authors: SS
authors: Okada
authors: Eliver Eid Bou
authors: EE
authors: Ghosn
authors: Noemi Nosomi
authors: NN
authors: Taniwaki
authors: Maria Rita
authors: MR
authors: Rodrigues
authors: Sandro Rogerio
authors: SR
authors: de Almeida
authors: Renato Arruda
authors: RA
authors: Mortara
authors: Momtchilo
authors: M
authors: Russo
authors: Ana
authors: A
authors: Campa
authors: Renata Chaves
authors: RC
authors: Albuquerque
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology*; D001402:B-Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D003594:Cytoplasmic Granules / Q000378:metabolism; D022162:Cytoplasmic Vesicles / Q000378:metabolism; D005434:Flow Cytometry; D006997:Hypochlorous Acid / Q000378:metabolism; D008264:Macrophages / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D051379:Mice; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000378:metabolism; D009504:Neutrophils / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D010529:Peritoneal Cavity / Q000166:cytology*; D009195:Peroxidase / Q000276:immunology / Q000378:metabolism*
chemical_list: D006997:Hypochlorous Acid; D009195:Peroxidase