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PubMed · 9129207

Monocytes from mobilized stem cells inhibit T cell function.

K Ino·R K Singh·J E Talmadge
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Abstract

Granulocyte-macrophage colony-stimulating factor, mobilized peripheral blood stem cell (PSC) products, and peripheral blood leukocytes posttransplantation contain cells that cause allogeneic and autologous T cell apoptosis. Isolation and characterization of these cells demonstrated that they were low-density (Percoll fractionation) CD14+ monocytes. T cells in PSC products have a depressed phytohemagglutinin (PHA) mitogenic response; however, purified CD4+ or CD8+ T cells exhibit a statistically normal mitogenic function. Furthermore, no T cell inhibitory activity was observed in CD14+, CD4+, and CD8+ cell-depleted fractions enriched in CD4- CD8- TCR alpha/beta+ T cells. Inhibition of T cell function by CD14+ monocytes required cell-cell contact, and the analyses of DNA fragmentation by Southern and TUNEL analysis demonstrates an activation-induced T cell apoptosis in the presence of CD14+ monocytes. Reverse-transcriptase polymerase chain reaction studies suggested that high levels of interleukin-10 or tumor necrosis factor gene transcripts in the PSC products may contribute to the inhibition of T cell function.

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ApoptosisCD8-Positive T-LymphocytesCell CommunicationCell MovementCytokinesFlow CytometryHematopoietic Stem CellsHumansLeukocytes, MononuclearLipopolysaccharide ReceptorsLymphocyte ActivationPhenotypePhytohemagglutininsT-LymphocytesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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K Ino, R K Singh, J E Talmadge. 1997. Monocytes from mobilized stem cells inhibit T cell function.. https://doi.org/10.1002/jlb.61.5.583

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