Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
Prog Mol Subcell Biol. 2022;61:131-143. doi: 10.1007/978-3-031-01237-2_6.
Leukocytes are immune cells derived from hematopoietic stem cells of the bone marrow which play essential roles in inflammatory and immune responses. In contrast to anucleate platelets and erythrocytes, leukocytes are differentiated from other blood cells by the presence of a nucleus, and consist of monocytes, neutrophils, lymphocytes, basophils, and eosinophils. Factors released from platelets mediate immune responses in part by recruitment and regulation of leukocyte activity. Platelet dense granules contain the highly anionic polymer polyphosphate (polyP) with monomer chain lengths of approximately 60-100 phosphates long, which are released into the microenvironment upon platelet activation. Recent studies suggest that polyP released from platelets plays roles in leukocyte migration, recruitment, accumulation, differentiation, and activation. Furthermore, bacterial-derived polyphosphate, generally consisting of phosphate monomer lengths in the hundreds to thousands, appear to play a role in pathogenic evasion of the host immune response. This review will discuss the effects of host and pathogenic-derived polyphosphate on leukocyte function.
白细胞是源自骨髓造血干细胞的免疫细胞，在炎症和免疫反应中发挥着重要作用。与无核血小板和红细胞不同，白细胞通过存在核而从其他血细胞中分化出来，包括单核细胞、中性粒细胞、淋巴细胞、嗜碱性粒细胞和嗜酸性粒细胞。血小板释放的因子通过招募和调节白细胞的活性在部分免疫反应中发挥作用。血小板致密颗粒含有高度阴离子聚合物多聚磷酸盐（polyP），单体链长约 60-100 个磷酸，在血小板激活时释放到微环境中。最近的研究表明，血小板释放的多聚磷酸盐在白细胞迁移、募集、积累、分化和激活中发挥作用。此外，细菌来源的多聚磷酸盐通常由数百到数千个磷酸单体组成，似乎在病原体逃避宿主免疫反应中发挥作用。本综述将讨论宿主和病原体来源的多聚磷酸盐对白细胞功能的影响。
