Reproductive Immunology Research Group
Prof. Dr. Júlia Szekeres
Group activities
The group investigates factors that influence embryo implantation and the normal course of pregnancy.
1. We have previously developed a non-invasive, rapid method based on flow cytometry determination of the number of DNA-containing extracellular vesicles (EVs) released by the embryo into the culture fluid to identify embryos with the best chance of implantation in the receptive endometrium.
2. EVs also play a role in the dialogue between embryo and mother. EVs produced by the embryo deliver different molecules to the maternal side. One of these is progesterone-induced blocking factor (PIBF), which mediates the immunological effects of progesterone and is essential for both implantation and pregnancy maintenance. PIBF transported by embryo-derived EVs affects maternal lymphocyte IL- 10 production. In the absence of PIBF, fewer mouse embryos are implanted, which is associated with increased NK activity, Th1-directed T cell differentiation and other immunological changes.
3. EVs express immune checkpoint ligands that play a role in the regulation of the immune response. Expression of immune checkpoint molecules is reduced on the surface of EVs produced by embryos with a poor tendency to implant.
4. Progesterone is essential for implantation and maintenance of pregnancy. Progesterone treatment is often used to prevent habitual miscarriage, although we do not know what endometrial concentrations of progesterone increase in serum are associated with the effect of treatment. After treating mice with different doses of progesterone, we will compare the progesterone concentrations isolated from the endometrium with the corresponding serum concentrations to determine the optimal dose that most effectively promotes embryo implantation.
5. During the laboratory procedures of assisted reproduction, embryos are exposed to light. To investigate the potential negative effects of this, we found that illumination of mouse embryos with white light induces DNA fragmentation in the nuclei and reduces the implantation capacity of the embryos.
6. In addition to its role in calcium homeostasis, vitamin D also affects reproduction, but little is known about its effects at different stages of gestation. In a mouse model we investigate the effects of calcitriol treatment at different points in the peri-implantation period on ovulation, embryo development and implantation success.
