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PubMed · 1348432

Integrin expression profiles during erythroid differentiation.

T Papayannopoulou·M Brice
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Abstract

To study the expression of integrins at the erythroid progenitor level we isolated selected populations of cells from human fetal liver after immunoadherence to anti-beta 2 integrin (CD18) coated plates. These CD18 adherent cells (CD18-Ad), in contrast to CD18 nonadherent cells (CD18-NAd), have a blastlike cell morphology and are highly enriched in all progenitor types (14% to 37% progenitors). By several criteria progenitor cells present in CD18-Ad cells appear to have a higher proliferative potential and diversity than the ones found in CD18-NAd, which were mostly later erythroid progenitors. Positivity of CD18-Ad cells with the common beta 2 integrin (CD18) is largely attributable to expression of alpha L (CD11a) chain, rather than alpha M (CD11b). CD11a is present in all types of progenitors, but it is selectively lost at later stages of erythroid differentiation/maturation. By contrast, CD11b appears to be virtually absent from all progenitors but it has an enhanced expression during granulomonocytic differentiation/maturation. In addition to beta 2 integrins, CD18-Ad cells express several other cytoadhesion molecules (VLA-4, VLA-5, I-CAM, H-CAM) as well as other progenitor cell antigens (CD34, HLA-DR, CD38). Cells expressing all these antigens were selectively enriched in CD18-Ad cells. Our data add new information on the regulation of CD11a and CD11b molecules in hematopoiesis and on the composite profile of integrin expression at several stages of erythroid differentiation.

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Antigens, CDCD11 AntigensCD18 AntigensCell CountCell DifferentiationCell SeparationErythroid Precursor CellsHumansImmune Adherence ReactionIntegrinsLiverReceptors, Leukocyte-AdhesionJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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T Papayannopoulou, M Brice. 1992-04-01. Integrin expression profiles during erythroid differentiation.. https://pubmed.ncbi.nlm.nih.gov/1348432/

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