| First Author | Hanayama R | Year | 2004 |
| Journal | J Immunol | Volume | 172 |
| Issue | 6 | Pages | 3876-82 |
| PubMed ID | 15004195 | Mgi Jnum | J:88624 |
| Mgi Id | MGI:3036396 | Doi | 10.4049/jimmunol.172.6.3876 |
| Citation | Hanayama R, et al. (2004) Expression of developmental endothelial locus-1 in a subset of macrophages for engulfment of apoptotic cells. J Immunol 172(6):3876-82 |
| abstractText | A major function of macrophages is to engulf apoptotic cells to prevent them from releasing noxious materials as they die. Milk fat globule-EGF-factor 8 (MFG-E8) is a glycoprotein secreted by activated macrophages that works as a bridge between apoptotic cells and phagocytes by specifically recognizing phosphatidylserine exposed on apoptotic cells. In this study, we found that developmental endothelial locus-1 (Del-1), originally identified as an embryonic endothelial cell protein that binds alphavbeta3 integrin, is structurally and functionally homologous to MFG-E8. That is, both consist of a signal sequence, two epidermal growth factor domains and two factor VIII-homologous domains (C1 and C2). Del-1 bound to the apoptotic cells by recognizing phosphatidylserine via the factor VIII-homologous domains with an affinity similar to that of MFG-E8. The phagocytic activity of NIH 3T3 cells against apoptotic cells was enhanced by Del-1 through an interaction between the epidermal growth factor domain in Del-1 and alphavbeta3 integrin expressed in the NIH 3T3 cells. Screening of primary macrophages and macrophage cell lines for the expression of MFG-E8 and Del-1 indicated that MFG-E8 and Del-1 are expressed in different sets of macrophages. These results suggest the existence of macrophage subsets that use MFG-E8 or Del-1 differently to engulf apoptotic cells. |
