Expression and modulation of prolactin receptor in immune cells: Induction of mRNA and proteins by dexamethasone

MORENO-SOSA, TAMARA; MARÍA B. SANCHEZ; FLAVIA J. NEIRA; MARTA SOAJE; ELISA O. PIETROBON; SUSANA R. VALDEZ; RIVERO V. E.; GRACIELA A. JAHN; MACKERN-OBERTI JP

Buenos Aires

Congreso; Reunión Anual de SOCIEDADES DE BIOCIENCIAS. SAIC. SAI. SAFIS; 2020

It is known that there is a relationship between hyperprolactinemia and autoimmunity. However, the role of prolactin receptor (PRL-R) in autoimmune development is still controversial. The aim of this work is to analyze the expression of PRL-R in murine immune cells, and determine whether PRL-R are modulated during stimulation with Concanavalin A (conA) and suppression with Dexamethasone (dexa) in healthy mice and three mice models for Lupus. For this end, splenocytes from C57BL/6 (C57), and lupic FcRIIb KO (RIIb), NZM, and MRL/MpJ-Faslpr (FAS) mice were stimulated with 1 µg/ml of conA or 1 µg/ml dexa and kept in culture for 24 hours. RNA from splenocytes was isolated using Trizol and retrotranscribed to cDNA to detect PRL-RL by qPCR. Protein determination was carried out by flow cytometry using Anti-CD4, Anti-CD19, and Anti-PRL-R. We found that splenocytes from RIIb mice have higher mRNA of PRL-RL expression than other strains. In CD4+ T cells from C57 mice PRL-R increased by suppression with dexa and did no changes when stimulated with conA. In contrast, in CD4+ T cells from FAS mice, PRL-R increased after conA and decreased with dexa, while the CD4+ T cells from RIIb and NZM mice displayed no changes. In CD19+ B cells from C57 and FAS mice, we observed an increase of total PRL-R when we stimulated with dexa and no changes with conA, while in CD19+ from RIIb and NZM mice, did not display changes. These results show a differential behavior of PRL-R expression in C57 mice compared with the lupic mice after stimulation with conA and dexa. The fact that C57 displayed low levels of PRL-R during activation but high in suppression gives us the notion that PRL-R may contribute to maintaining a cellular immune balance by limiting PRL trophic effects. By contrast, the high levels of PRL-R during activation in FAS mice suggest an exacerbated trophic effect of PRL. Our data show that differential PRL-R expression in immune cells may contribute to regulate the immune response.