Macrophages are distinguished from circulating monocytes Biology essay
Macrophages are a type of white blood cells that play an integral role in the immune system and are involved in phagocytizing foreign antigens, such as bacteria. They are able to present these antigens to other immune cells, such as T cells, for further destruction. Macrophages also play a role in wound healing and tissue repair. Monocytes and macrophages play a central role in the initiation and resolution of inflammation, mainly through phagocytosis, the release of inflammatory cytokines, reactive oxygen species ROS and the activation of the acquired immune system. Monocytes and macrophages originate from a common myeloid precursor. Ly6C blood monocytes invade tissues and become macrophages, for example in the intestines, lungs and dermis, monocyte-derived macrophages or monocyte-derived tissue residents. A macrophage classification system. Monocytes that infiltrate tissues in response to infection or inflammation rapidly differentiate into macrophages that can exhibit a wide range of activation states. Using single-cell transcriptomics, Sanin et al. develop a framework for classifying macrophage activation states into Various Macrophages have long been considered terminally differentiated immune cells that develop from monocytes and are unable to enter the cell cycle 1 ,2,3. However, recent studies challenge this view and propose that macrophages can indeed enter the cell cycle and self-renew2,4. Furthermore, macrophages can develop from embryonic development. This resident macrophage lineage is genetically, developmentally, and functionally distinct from macrophages derived from hematopoietic stem cell HSCs and circulating, 9, 11, 12. Taken together, their findings suggest that circulating monocytes transition to interstitial macrophages and Mo-AMs. Monocytes contribute to both the adaptive and innate arms of the immune system. Although they can initiate inflammatory responses upon injury, they also participate in normal and abnormal repair processes of damaged tissue. Monocytes and macrophages are essential components of the innate immune system and play a multifaceted role in homeostasis and immunity. These phenotypically distinct mononuclear phagocytes play different roles at different stages and contribute to pathophysiology in different forms, making them a potentially attractive therapeutic agent. 1.1. Inflammatory monocytes and macrophages. Monocytes and macrophages are a central component of the innate immune system and exert an important function in orchestrating inflammation. They not only play a crucial role in the generation of inflammatory mediators and in the regulation of the innate and adaptive immune system. For decades it was believed that monocytes are simply circulating precursors of tissue-resident macrophages, but it is now understood that they have independent functions during the steady state. Monocytes are highly plastic innate immune cells that exhibit significant heterogeneity during homeostasis, inflammation, and tumorigenesis. Tumor-induced systemic and local microenvironmental changes influence monocyte phenotype, differentiation, and distribution. Meanwhile, monocytes and their related cell subsets, Metastasis, are responsible for most cancer-related deaths and proceed through multiple steps. Several lines of evidence have demonstrated an indispensable involvement of macrophages present at primary tumor sites at various steps of metastasis, from the growth of the primary tumor to the,