Uterine natural killer cells are targets for a trophoblast cell-specific cytokine, prolactin-like protein A.
PRL-like protein A (PLP-A) is a member of the PRL family expressed in trophoblast cells coincident with establishment of the chorioallantoic placenta. The purpose of this investigation was to identify targets for PLP-A. Using an alkaline phosphatase-tagging strategy, we show that PLP-A specifically interacts with a population of natural killer (NK) lymphocytes within the mesometrial compartment of decidua from pregnant and pseudopregnant rats. These observations are supported by the codistribution of PLP-A targets with cells expressing the rat NK cell surface marker, gp42, the absence of PLP-A binding in conceptuses from NK cell-deficient tg epsilon26 mice, and the specific interaction of PLP-A with a rat NK cell line, RNK-16. We have further demonstrated that PLP-A effectively suppresses RNK-16 cell cytolytic activities. Our results provide evidence for a new paradigm of embryonic-maternal communication involving a PLP-A signaling pathway between trophoblast cells and uterine NK lymphocytes.
Müller
H
H
Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City 66160, USA.
Liu
B
B
Croy
B A
BA
Head
J R
JR
Hunt
J S
JS
Dai
G
G
Soares
M J
MJ
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005260:Female; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism / Q000494:pharmacology; D014599:Uterus / Q000378:metabolism*
D011257:Pregnancy Proteins; C502143:Prl4a1 protein, rat; C502142:Prlpa protein, mouse; D011993:Recombinant Fusion Proteins; D000469:Alkaline Phosphatase