Effect of Pregnancy Specific β1-Glycoprotein on the Replicative Potential of Naïve T Cells and Immune Memory T Cells

We studied the effects of pregnancy-specific β1-glycoprotein (PSG) on the replicative potential of naïve T cells (CD45RA⁺) and immune memory T cells (CD45R0⁺) in vitro by evaluating the expression of the hTERT gene in combination with the proliferative activity of cells. Human PSG was obtained by the author's patented method of immunopurification using a biospecific sorbent with subsequent removal of immunoglobulin contamination on a HiTrap Protein G HP column. We used monocultures of CD45RA⁺ and CD45R0⁺ lymphocytes isolated from peripheral blood mononuclear cells of reproductive-age women. It was found that PSG in physiological concentrations inhibited the expression of the hTERT gene mRNA in naïve T cells and immune memory T cells and simultaneously reduced the number of proliferating T cells estimated by the differential gating method. At the same time, PSG reduced CD71 expression only on naïve T cells without affecting this molecule on immune memory T cells. Thus, PSG decreased the replication potential and suppressed the proliferation of T cells and immune memory T cells, which in the context of pregnancy can contribute to the formation of immune tolerance to the semi-allogeneic embryo.