RT Book, Section A1 Douglas, Steven D. A1 Douglas, Anne G. A2 Kaushansky, Kenneth A2 Prchal, Josef T. A2 Burns, Linda J. A2 Lichtman, Marshall A. A2 Levi, Marcel A2 Linch, David C. SR Print(0) ID 1180445434 T1 Production, Distribution, and Activation of Monocytes and Macrophages T2 Williams Hematology, 10e YR 2021 FD 2021 PB McGraw-Hill Education PP New York, NY SN 9781260464122 LK accessmedicine.mhmedical.com/content.aspx?aid=1180445434 RD 2024/03/28 AB SUMMARYMonocytes and macrophages play important roles in human biology, both as components of the hematopoietic system and within the stroma and tissue microenvironment, where they contribute trophic and clearance functions. They constitute a widely dispersed cellular system throughout the body, interacting with host cells and foreign invaders through their versatile biosynthetic and secretory responses, all designed to maintain physiologic homeostasis. Included within the “family” of monocyte and macrophages are specialized migratory or sessile phagocytes, present within the circulation and extravascular tissue compartment, which contribute to diverse pathologic processes directly and through their production of bioactive products. Monocytes and macrophages display much heterogeneity and plasticity. The origin, lifespan, and functions of the monocyte are the focus of this chapter, including their relevance to health and disease in humans, based on current understanding of their properties. The relationship of monocytes and macrophages to dendritic cells and monocyte-derived cells with a specialized immunologic role in T-lymphocyte activation are described. Together, macrophages and dendritic cells are major antigen-presenting cells, contributing to host defense, innate and acquired immunity, and inflammation, as well as noninfectious disease processes, both within and outside the lymphohematopoietic organs.