Aim: 

Presence of carbohydrates in different cell types in human placenta suggests their major role in maternal-fetal exchanges, intercellular adhesion, cellular metabolism and villous vessels branching. Although studies on glycoconjugates distribution in human placenta have been already performed, their role in placenta development is still unclear. We investigated sugar chain expression and role of core-1 O- and N-glycans in human placenta.

Methods: 

paraffin sections from first trimester placenta were used for lectin histochemistry using Peanut agglutinin (PNA) directed to core-1 O-glycans and Concanavalin A (ConA) directed to pentasaccharidic core of N-glycans. HTR8 trophoblast cells were incubated under low (3%) or standard (20%) oxygen tension and levels of core-1 O- and N-glycans were measured by FACS. Cultures were exposed to PNA and ConA and assayed for viability and proliferation.

Results: 

ConA staining was widely distributed in all cellular elements of the villi, PNA staining was restricted to villous cytotrophoblast. Core-1 O-glycans expression level was significantly increased at 3% of oxygen, N-glycans expression was not influenced by oxygen tensions. Treatment of cell cultures with PNA resulted in significant increase of cell proliferation as compared to untreated or ConA- treated cultures.

Conclusions: 

post-translational modifications such as specific glycosylation are modulated by low oxygen tension and play a key role in determining trophoblast differentiation.