{"title":"人吞噬细胞的粘附导致独特的f -肌动蛋白池的特征性重组和重新分配。","authors":"R G Watts","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>The F-actin based microfilamentous cytoskeleton (MFC) provides mobility for phagocytic immune cells including polymorphonuclear leukocytes (PMNs) and macrophages (MOs). In PMNs in suspension, the MFC is organized into two distinct F-actin pools [Triton Insoluble F-actin-(TIF), which form the sub-membranous, 3D actin meshwork and Triton Soluble F-actin (TSF), which exists as short oligomers] in equilibrium with G-actin. The structure of F-actin pools in adherent cells is unknown despite the fact that phagocytes are adherent in tissues in vivo. In order to determine the structure of F-actin pools in adherent phagocytes, human PMNs were isolated and allowed to adhere to plastic for 1 hour at 37 degrees C. Adherent cells were collected, actin pools separated and quantified by SDS-PAGE and compared to nonadherent PMNs in suspension. Likewise, the nonadherent human myeloid cell line U937 was induced to MO morphology and adherence by exposure to TPA (10(-6) M x 3 days) and similarly evaluated. Adherence of PMNs to plastic resulted in 75 +/- 15% adherence (n = 3). TPA differentiation of U937 cells resulted in 81 +/- 15% adherence (n = 10). In both cells, adherence resulted in a statistically significant increase in TIF, a decrease in TSF, and little to no change in G-actin. Basal, nonadherent PMNs in suspension contain TIF 40 +/- 0%, TSF 20 +/- 4%, and G-actin 40 +/- 4%, n = 3, whereas adherent PMNs contain TIF 61 +/- 3%, TSF 5 +/- 5%, G-actin 34 +/- 1%, n = 3. Basal U937 contain TIF 41 +/- 9%, TSF 17 +/- 6%, and G-actin 42 +/- 13%, n = 7. Adherent MO-like U937 contain TIF 53 +/- 4%, TSF 9 +/- 5%, and G-actin 38 +/- 4%. The results show that phagocyte adherence leads to a characteristic reorganization of actin pool structure that is remarkably quantitatively similar to, yet mechanistically distinct from, reorganization by chemotactic factor activation in suspension. Adherence-induced TIF-actin growth results exclusively from conversion of TSF-actin to TIF-actin.</p>","PeriodicalId":79440,"journal":{"name":"Hematopathology and molecular hematology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Adherence of human phagocytes results in characteristic reorganization and redistribution of distinct F-actin pools.\",\"authors\":\"R G Watts\",\"doi\":\"\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>The F-actin based microfilamentous cytoskeleton (MFC) provides mobility for phagocytic immune cells including polymorphonuclear leukocytes (PMNs) and macrophages (MOs). In PMNs in suspension, the MFC is organized into two distinct F-actin pools [Triton Insoluble F-actin-(TIF), which form the sub-membranous, 3D actin meshwork and Triton Soluble F-actin (TSF), which exists as short oligomers] in equilibrium with G-actin. The structure of F-actin pools in adherent cells is unknown despite the fact that phagocytes are adherent in tissues in vivo. In order to determine the structure of F-actin pools in adherent phagocytes, human PMNs were isolated and allowed to adhere to plastic for 1 hour at 37 degrees C. Adherent cells were collected, actin pools separated and quantified by SDS-PAGE and compared to nonadherent PMNs in suspension. Likewise, the nonadherent human myeloid cell line U937 was induced to MO morphology and adherence by exposure to TPA (10(-6) M x 3 days) and similarly evaluated. Adherence of PMNs to plastic resulted in 75 +/- 15% adherence (n = 3). TPA differentiation of U937 cells resulted in 81 +/- 15% adherence (n = 10). In both cells, adherence resulted in a statistically significant increase in TIF, a decrease in TSF, and little to no change in G-actin. Basal, nonadherent PMNs in suspension contain TIF 40 +/- 0%, TSF 20 +/- 4%, and G-actin 40 +/- 4%, n = 3, whereas adherent PMNs contain TIF 61 +/- 3%, TSF 5 +/- 5%, G-actin 34 +/- 1%, n = 3. Basal U937 contain TIF 41 +/- 9%, TSF 17 +/- 6%, and G-actin 42 +/- 13%, n = 7. Adherent MO-like U937 contain TIF 53 +/- 4%, TSF 9 +/- 5%, and G-actin 38 +/- 4%. The results show that phagocyte adherence leads to a characteristic reorganization of actin pool structure that is remarkably quantitatively similar to, yet mechanistically distinct from, reorganization by chemotactic factor activation in suspension. Adherence-induced TIF-actin growth results exclusively from conversion of TSF-actin to TIF-actin.</p>\",\"PeriodicalId\":79440,\"journal\":{\"name\":\"Hematopathology and molecular hematology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1996-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Hematopathology and molecular hematology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Hematopathology and molecular hematology","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Adherence of human phagocytes results in characteristic reorganization and redistribution of distinct F-actin pools.
The F-actin based microfilamentous cytoskeleton (MFC) provides mobility for phagocytic immune cells including polymorphonuclear leukocytes (PMNs) and macrophages (MOs). In PMNs in suspension, the MFC is organized into two distinct F-actin pools [Triton Insoluble F-actin-(TIF), which form the sub-membranous, 3D actin meshwork and Triton Soluble F-actin (TSF), which exists as short oligomers] in equilibrium with G-actin. The structure of F-actin pools in adherent cells is unknown despite the fact that phagocytes are adherent in tissues in vivo. In order to determine the structure of F-actin pools in adherent phagocytes, human PMNs were isolated and allowed to adhere to plastic for 1 hour at 37 degrees C. Adherent cells were collected, actin pools separated and quantified by SDS-PAGE and compared to nonadherent PMNs in suspension. Likewise, the nonadherent human myeloid cell line U937 was induced to MO morphology and adherence by exposure to TPA (10(-6) M x 3 days) and similarly evaluated. Adherence of PMNs to plastic resulted in 75 +/- 15% adherence (n = 3). TPA differentiation of U937 cells resulted in 81 +/- 15% adherence (n = 10). In both cells, adherence resulted in a statistically significant increase in TIF, a decrease in TSF, and little to no change in G-actin. Basal, nonadherent PMNs in suspension contain TIF 40 +/- 0%, TSF 20 +/- 4%, and G-actin 40 +/- 4%, n = 3, whereas adherent PMNs contain TIF 61 +/- 3%, TSF 5 +/- 5%, G-actin 34 +/- 1%, n = 3. Basal U937 contain TIF 41 +/- 9%, TSF 17 +/- 6%, and G-actin 42 +/- 13%, n = 7. Adherent MO-like U937 contain TIF 53 +/- 4%, TSF 9 +/- 5%, and G-actin 38 +/- 4%. The results show that phagocyte adherence leads to a characteristic reorganization of actin pool structure that is remarkably quantitatively similar to, yet mechanistically distinct from, reorganization by chemotactic factor activation in suspension. Adherence-induced TIF-actin growth results exclusively from conversion of TSF-actin to TIF-actin.