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CD47 in Erythrocyte Ageing and Clearance - the Dutch Point of View.

ABSTRACT: Recently, an important role for CD47, a well-known 'don't eat me' signal, in the clearance of aged erythrocytes was revealed. Experimental data support the conversion of CD47 from a 'don't eat me' to an 'eat me' signal through a conformational change in CD47. Intriguingly, erythrocyte phagocytosis after this switch seems to be mediated by the same receptor that normally signals inhibition of phagocytosis, SIRP?. In this review, the possible molecular mechanisms leading to this conformational change in CD47 as well as the possible signal transduction events leading to phagocytosis after this switch are discussed. Lastly, the consequences of this newly identified mode of erythrocyte phagocytosis for the clearance of aged erythrocytes during normal turnover and after erythrocyte transfusion are addressed.

SUBMITTER: Burger P

PROVIDER: S-EPMC3678269 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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CD47 in Erythrocyte Ageing and Clearance - the Dutch Point of View.

Burger Patrick P de Korte Dirk D van den Berg Timo K TK van Bruggen Robin R

Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie 20120906 5

Recently, an important role for CD47, a well-known 'don't eat me' signal, in the clearance of aged erythrocytes was revealed. Experimental data support the conversion of CD47 from a 'don't eat me' to an 'eat me' signal through a conformational change in CD47. Intriguingly, erythrocyte phagocytosis after this switch seems to be mediated by the same receptor that normally signals inhibition of phagocytosis, SIRPα. In this review, the possible molecular mechanisms leading to this conformational cha ...[more]

PMID: 23801927

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