Format

Send to

Choose Destination
See comment in PubMed Commons below
Blood. 1992 Dec 1;80(11):2735-9.

Expression and activity of the multidrug resistance P-glycoprotein in human peripheral blood lymphocytes.

Author information

1
Department of Genetics, University of Illinois, Chicago 60612.

Abstract

P-glycoprotein (P-gp), the product of the MDR1 (multidrug resistance) gene, is a transmembrane efflux pump for different lipophilic compounds, including many anticancer drugs and fluorescent dyes. We have previously reported that the efflux of fluorescent dyes from lymphoid cells of human bone marrow was directly correlated with the cellular P-gp content. In the present study, we show that human peripheral blood lymphocytes (PBL) also express P-gp, and that P-gp expression correlates with the efflux of fluorescent dyes from PBL. This efflux was suppressed not only by chemical inhibitors of P-gp but also by a P-gp-specific monoclonal antibody UIC2, thus providing direct evidence that it was mediated by P-gp. We have also characterized dye efflux and UIC2 reactivity in specific PBL subsets. P-gp was expressed in the majority of CD56+, CD8+, and CD20+ lymphocytes, but in less than one half of CD4+ cells. P-gp-mediated dye efflux was highly heterogeneous relative to the expression of CD56RA, CD56RO, Leu-8, and HLA-DR antigens. No significant P-gp activity was detectable in CD14+ monocytes. MDR1 expression in normal lymphocytes may be a determinant of multidrug resistance in the corresponding malignancies.

PMID:
1360267
[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center