Prolactin receptor expression in human hematopoietic tissues analyzed by flow cytofluorometry.
PRL receptor (PRL-R) expression has been analyzed in human hematopoietic tissues using flow cytofluorometric analysis with a series of biotinylated monoclonal antibodies (mAbs) directed against the extracellular domain of the rat liver PRL-R. In the thymus, more than 75% of cells were labeled by the anti-PRL-R mAb. Regarding PRL-R expression in the four T-cell subsets defined by CD4/CD8 expression, the majority of cells expressed low receptor levels, whereas a minority of double negative (CD4-CD8-) and single positive CD4+ cells were strongly labeled by the anti-PRL-R mAb. In the peripheral blood, an average of 80% of lymphoid cells, comprising all B-cells, all monocytes, and 75% of T-cells, were consistently PRL-R positive. Regarding T-cell subsets, similar percentages of PRL-R+ cells were observed in CD4+ and CD8+ peripheral lymphocytes (70-75%), and the density of labeling per cell was significantly lower than that occurring in B-cells or monocytes. Interestingly, the intensity of labeling significantly increased in peripheral T-cells after T-cell activation. The ubiquitous distribution of PRL-R in bone marrow stem cells, B-cells, monocytes, and T-cells was confirmed by the positive staining obtained in a set of human lymphoid cell lines. These data along with those showing that the PRL gene is specifically expressed in human T-cells suggest that lymphocyte PRL may act in a paracrine or autocrine fashion in both central and peripheral lymphoid organs.
Dardenne
M
M
CNRS URA 1461, Hôpital Necker, Paris, France.
de Moraes
M do C
Mdo C
Kelly
P A
PA
Gagnerault
M C
MC
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D001853:Bone Marrow / Q000378:metabolism; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D005260:Female; D005434:Flow Cytometry; D006410:Hematopoiesis; D006801:Humans; D008213:Lymphocyte Activation; D008221:Lymphoid Tissue / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011981:Receptors, Prolactin / Q000378:metabolism*; D013602:T-Lymphocytes, Cytotoxic / Q000378:metabolism; D006377:T-Lymphocytes, Helper-Inducer / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism; D013950:Thymus Gland / Q000378:metabolism
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D016827:CD8 Antigens; D011981:Receptors, Prolactin