RRC ID 44298
Author Miki Y, Oguri E, Hirano K, Beppu M.
Title Macrophage recognition of cells with elevated calcium is mediated by carbohydrate chains of CD43.
Journal Cell Struct Funct
Abstract Macrophages remove deteriorating cells (those undergoing apoptosis and oxidation) via poly-N-acetyllactosaminyl chains on CD43 caps, a major cell-surface glycoprotein. Unusually high intracellular calcium levels are also deteriorating for cells and tissue. Here we artificially elevated calcium levels in cells and examined the mechanism by which this elevation was resolved by macrophages. Results showed that treatment with the calcium ionophore A23187 and ionomycin induces capping of CD43 on Jurkat cells, which are subsequently recognized and phagocytosed by macrophages, indicating that macrophages regard cells with elevated calcium as targets for removal. Further tests showed that A23187- and ionomycin-treated Jurkat cells did not induce apoptotic changes such as DNA fragmentation or phosphatidylserine expression, indicating that these cells were removed despite still being viable. Jurkat cells pretreated with anti-CD43 antibody or those with poly-N-acetyllactosaminyl chains containing oligosaccharides inhibited macrophage binding, indicating that macrophages recognize the poly-N-acetyllactosaminyl chains on CD43. Binding was also inhibited by treating macrophages with anti-nucleolin antibody, indicating that recognition occurs through nucleolin, a cell-surface receptor. Further, nucleolin-transfected HEK293 cells bound A23187-treated cells, and this binding was inhibited by in the presence of oligosaccharides. Taken together, these results show that elevated calcium levels induce CD43 capping, and macrophages remove the cells if their nucleolin receptors can bind to the poly-N-acetyllactosaminyl chains of capped CD43.
Volume 38(1)
Pages 43-54
Published 2013-1-1
DOI 10.1247/csf.12024
PMID 23400223
MeSH Apoptosis* / drug effects Apoptosis* / genetics Calcimycin / pharmacology Calcium / metabolism Calcium / pharmacology* Carbohydrates / chemistry DNA Fragmentation / drug effects HEK293 Cells Humans Ionomycin / pharmacology Jurkat Cells Leukosialin / chemistry Leukosialin / metabolism* Macrophages / drug effects Macrophages / metabolism Oligosaccharides / metabolism Phosphoproteins / metabolism* Protein Binding / drug effects RNA-Binding Proteins / metabolism*
IF 2.429
Times Cited 5
Human and Animal Cells Jurkat