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PubMed · 10933602

Microenvironmental influences on human B-cell development.

F E Bertrand·C E Eckfeldt·J R Fink·A S Lysholm·J A Pribyl·N Shah·T W LeBien
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Abstract

Mammalian B-cell development can be viewed as a developmental performance with several acts. The acts are represented by checkpoints centered around commitment to the B-lineage and functional Ig gene rearrangement--culminating in expression of the pre-B-cell receptor (pre-BCR) and the BCR. Progression of cells through these checkpoints is profoundly influenced by the fetal liver and adult bone marrow (BM) stromal cell microenvironments. Our laboratory has developed a model of human B-cell development that utilizes freshly isolated/non-transformed human BM stromal cells as an in vitro microenvironment. Human CD34+ hematopoietic stem cells plated in this human BM stromal cell microenvironment commit to the B lineage and progress through the pre-BCR and BCR checkpoints. This human BM stromal cell microenvironment also provides survival signals that prevent apoptosis in human B-lineage cells. Human B-lineage cells exhibit differential expression of Notch receptors and human BM stromal cells express the Notch ligand Jagged-1. These results suggest a potential role for Notch in regulating B-lineage commitment and/or progression through the pre-BCR and BCR checkpoints.

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ApoptosisB-LymphocytesBone Marrow CellsCalcium-Binding ProteinsCell DifferentiationCell DivisionCell LineageCytokinesEmbryonic and Fetal DevelopmentHematopoietic Stem CellsHumansIntercellular Signaling Peptides and ProteinsInterleukin-7Jagged-1 ProteinMembrane ProteinsModels, BiologicalReceptors, NotchSerrate-Jagged ProteinsSignal TransductionStromal CellsThymic Stromal LymphopoietinJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.Review

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BibTeXRIS

F E Bertrand, C E Eckfeldt, J R Fink, A S Lysholm, J A Pribyl, N Shah, T W LeBien. 2000. Microenvironmental influences on human B-cell development.. https://pubmed.ncbi.nlm.nih.gov/10933602/

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