EFFECT OF TROPHOBLAST CELL EXOSOMES ON HUMAN HOFBAUER CELLS PHENOTYPE AND FUNCTION

DANIEL PAPARINI; ESTEBAN GRASSO; BRENDA LARA; ANA SCHAFIR; VANESA HAUK; VOTA, DAIANA; SOLEDAD GORI; FATIMA MERECH; GUILLERMINA CALO; M AGUSTINA ARSLANIAN; J IGNACIO ABASOLO; GUSTAVO IZBIZKY; ROSANNA RAMHORST; CLAUDIA PÉREZ LEIRÓS

Mar del Plata

Congreso; REUNIÓN CONJUNTA SAIC SAI&FAIC SAFIS 2022; 2022

SAIC, SAIC, SAFIS

Hofbauer cells (HBC) are the only foetal immune cell population within the stroma of healthy placenta. However, the functional properties of these cells are poorly described. HBCs are transcriptionally similar to yolk sac macrophages. Trophoblast cells release exosomes (Ex) that regulate target cell function during pregnancy. Here we studied the profile of HBC modulated by trophoblast exosomes, physiological or pathological stimuli. Methodology: Trophoblast cell line (Swan 71-Tb) Ex were obtained by differential centrifugation and characterized. HBC were isolated from human term placentas (N= 25) by enzymatic digestion. They were cultured with 75-100 ng/ ml Tb-Ex for 18 h to assess phenotypic profile, glucose uptake and lipid droplets formation by flow cytometry. 100 nM vasoactive intestinal peptide (VIP) or 100 ng/ml E. coli lipopolysaccharide (LPS) were used as anti or proinflammatory stimuli. HBC supernatant was used to study endothelial cell (EC) migration by wound healing assay.Results: Tb-Ex increased antiinflammatory marker CD39 (*P<0.05 vs. basal), without changing IL-1β production in CD14+ HBC, like the effect of VIP. HBC stimulated with LPS increased CD11c, IL-1β and CD39 expression (*P<0.05 vs. basal). Only when HBC were cultured with Tb-Ex but not with VIP, EC migration was enhanced (45±3.6% vs. 35±4.5%, results are expressed as Mean ± SEM, *P<0.05). Interestingly, phenotypic differences were found between HBC from female (F-HBC) and male (M-HBC) new-born placentas as a higher % of CD14/CD163+ cells in F-HBC (*P<0.05) and lower secretion of IL-1β (*P<0.05) compared to M-HBC. Also, F-HBC displayed higher CD36 expression (*P<0.05) and lipid droplets accumulation than M-HBC without changes in glucose uptake suggesting different metabolic profiles. Conclusions: Trophoblast cell exosomes promote an M2-like phenotype on HBC and endothelial cell migration, consistent with a favouring role at placentation.