Molecular mechanisms of erythrophagocytosis. Characterization of the senescent erythrocytes that are phagocytized by macrophages

Autor: Françoise Russo-Marie, Jean Montreuil, Daniela Bratosin, Jean Marie Freyssinet, Joël Mazurier, David Aminoff, Jean Pierre Tissier, Jean Jacques Huart, Christian Slomianny, Jérôme Estaquier, Jean-Claude Ameisen
Rok vydání: 1997
Předmět:
Zdroj: Comptes Rendus de l'Académie des Sciences - Series III - Sciences de la Vie. 320:811-818
ISSN: 0764-4469
Popis: We have recently developed a flow cytometric assay for the quantitation of erythrophagocytosis, using PKH 26-labeled erythrocytes as the target cells. Using this assay we have shown that there is extensive phagocytosis of desialylated erythrocytes. Furthermore, we have demonstrated that it is the densest population of erythrocytes obtained on a self-forming gradient of Percoll that shows the greatest susceptibility to phagocytosis. We designate this population of erythrocytes as fraction X; it is even denser than the fraction 5 found previously. This population of erythrocytes corresponds to zone X previously seen in the dot-plot of the flow cytometric analyses of human erythrocytes. Further scrutiny of this fraction indicates that a) it shows the greatest reactivity with annexin V, which is specific for the detection of phosphatidylserine (PS) exposed on the outer leaflet of the erythrocyte membrane, b) it is the most susceptible to erythrophagocytosis by resident murine peritoneal macrophages, and c) this erythrophagocytosis of PKH 26-labeled erythrocytes can be inhibited by annexin V and by liposomes containing PS. Scanning electron microscopy of fraction X shows two populations of erythrocytes: (A) spheroechinocytes with filipodes and (B) echinocytes without filipods. After a 2-h period of phagocytosis, the cells remaining in fraction X show a decrease in population A, commensurate with a decrease in reactivity with FITC-labeled annexin V from 65.5 to 24%.
Databáze: OpenAIRE