Prolactin Acts on Myeloid Progenitors to Modulate SMAD7 Expression and Enhance Hematopoietic Stem Cell Differentiation into the NK Cell Lineage.

ABSTRACT: Numerous cell types modulate hematopoiesis through soluble and membrane bound molecules. Whether developing hematopoietic progenitors of a particular lineage modulate the differentiation of other hematopoietic lineages is largely unknown. Here we aimed to investigate the influence of myeloid progenitors on CD34⁺ cell differentiation into CD56⁺ innate lymphocytes. Sorted CD34⁺ cells cultured in the presence of stem cell factor (SCF) and FMS-like tyrosine kinase 3 ligand (FLT3L) give rise to numerous cell types, including progenitors that expressed the prolactin receptor (PRLR). These CD34⁺PRLR⁺ myeloid-lineage progenitors were derived from granulocyte monocyte precursors (GMPs) and could develop into granulocytes in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) in vitro. Moreover, CD34⁺PRLR⁺ myeloid progenitors lacked lymphoid developmental potential, but when stimulated with prolactin (PRL) they increased the differentiation of other CD34⁺ cell populations into the NK lineage in a non-contact dependent manner. Both mRNA and protein analyses show that PRL increased mothers against decapentaplegic homolog 7 (SMAD7) in CD34⁺PRLR⁺ myeloid cells, which reduced the production of transforming growth factor beta 1 (TGF-?1), a cytokine known to inhibit CD56⁺ cell development. Thus, we uncover an axis whereby CD34⁺PRLR⁺ GMPs inhibit CD56⁺ lineage development through TGF-?1 production and PRL stimulation leads to SMAD7 activation, repression of TGF-?1, resulting in CD56⁺ cell development.

SUBMITTER: Tufa DM 

PROVIDER: S-EPMC7156717 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature