Leptin promotes HLA-G expression on placental trophoblasts via the MEK/Erk and PI3K signaling pathways

Authors
Barrientos, Gabriela Laura; Toro, Ayelen Rayen; Monschanski, P; Cohen, M.; García, Mariana Gabriela; Rose, M.; Maskin, Bernardo; Sanchez Margalet, V.; Blois, Sandra M.; Varone, Cecilia Laura
Publication Year
2015
Language
English
Format
article
Status
Published version
Description
Introduction: The development of the human haemochorial placenta requires complex regulatory mechanisms to protect invasive trophoblast cells from cytotoxic responses elicited by maternal immune cells. Leptin, the adipocyte derived hormone encoded by the Lep gene, is synthesized by placental trophoblasts and exerts pleiotropic effects on the immune system, including the promotion of inflammation and the activation of T cell responses. Methods: To address its possible involvement in the modulation of maternal immune responses during pregnancy, we investigated the effect of leptin on the expression of the class Ib histocompatibility antigen HLA-G as one of the chief immunosuppressive strategies used by trophoblast cells. Results: In vitro incubation of the trophoblast derived Swan 71 and JEG-3 cell lines with 25-50 ng/ml recombinant leptin significantly boosted HLA-G mRNA and protein expression, and this effect was abrogated upon pharmacological inhibition of the PI3K-Akt and MEK-Erk signaling pathways. A similar stimulatory effect of leptin was observed in term placental tissue explants, though 10-fold higher doses were required for stimulation. Further, JEG-3 cells treated with a leptin antisense oligodeoxynucleotide displayed decreased HLA-G expression levels, which were partially recovered by addition of stimulating doses of exogenous hormone. Immunofluorescence and qPCR analysis confirmed leptin biosynthesis in placental tissue, further showing that invasive extravillous trophoblast cells were a main source of this hormone during the first trimester of normal pregnancies. Discussion: Taken together, our results show that leptin acts as an autocrine/paracrine signal promoting HLA-G expression in placental trophoblasts suggesting an important role in the regulation of immune evasion mechanisms at the fetal maternal interface.
Fil: Barrientos, Gabriela Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina
Fil: Toro, Ayelen Rayen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina
Fil: Monschanski, P. Medicine University Berlin; Alemania
Fil: Cohen, M.. Universidad de Ginebra; Suiza
Fil: García, Mariana Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral. Facultad de Ciencias Biomédicas. Laboratorio de Terapia Genética; Argentina
Fil: Rose, M.. Medicine University Berlin; Alemania
Fil: Maskin, Bernardo. Hospital Nacional Profesor A. Posadas; Argentina
Fil: Sanchez Margalet, V.. Universidad de Sevilla; España
Fil: Blois, Sandra M.. Medicine University Berlin; Alemania
Fil: Varone, Cecilia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina
Subject
HLA-G
LEPTIN
PLACENTA
SIGNAL TRANSDUCTION
Otras Ciencias Biológicas
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/46904