21361A

21361A
Caption: Tissue macrophages, T lymphocytes (2) and human red blood cells from a leg wound. * Note in this image one monocyte (blue) that has migrated into the wound area, is still developing into a tissue macrophage. A tissue macrophage is a large, mature phagocyte that can ingest and destroy invading microbes, foreign particles, cancerous or diseased cells and cellular debris. A monocyte is a circulating phagocyte that ingests microbes, invading particles, and cellular debris. Monocytes leave the blood stream and usually mature into tissue macrophages. Monocytes and macrophages are both part of the reticuloendothelial system. Lymphocytes are involved in the specific immune response and are composed mainly of precursor T cells and B cells (pre-T cells and B cells). Pre-T cells and B cells are subsets of lymphocytes that originate in the red bone marrow from hematopoietic stem cells. Pre-T cells (also known as T lymphocytes) circulate in the blood before migrating to the thymus where they develop into specialized cells (helper T cells and killer T cells) that are able to identify antigens and infected tissue cells.
Magnification*: x800
Type: SEM
Copyright 2002 Dennis Kunkel Microscopy, Inc.
Keywords: 03.01.02,21361A,helper T cell,hematopoietic,histiocyte,immune response,killer T cell,leukocyte,macrophage,medical,monocyte,monohistiocytic series,phagocyte,phagocytic,phagocytosis,pre-T cell,red blood cells,reticuloendothelial system,T cell,T lymphocyte,tissue macrophage,white blood cell,white blood cells,wound,SEM