KI ReproNET activities
KI ReproNET monthly organizes webinars and annual symposia. Additionally, this homepage serves as a platform for sharing information on open positions, relevant events, and news.
Webinar schedule for the spring:
Start time: 12:15 pm (online)
Format: 30 min talk + 10 min QA
Zoom link
Meeting ID: 688 0992 0689
Passcode: 021412
Tuesday the 11th of February
鈥淗uman embryonic genome activation in real life and in vitro鈥
Webinar chair and presentation summary: Nina Boskovic
Human Embryonic Genome Activation in real life and in vitro- by Prof. Juha Kere
The seminar discussed the early stages of human embryo development, focusing on the role of the DUX4 gene. DUX4 transcripts appear transiently in zygotes, and fourfold degradation of oocyte-specific mRNAs occurs until the 4-cell stage. Embryonic genome activation (EGA) begins at this stage with the transcription of 32 mRNAs, including several PRDL homeobox family transcription factors.
Recently, Prof. Juha Kere鈥檚 group, using whole-genome methods, showed that DUX4 has a major role in chromatin remodeling and enhancer activation, interacting with Mediator proteins. Downregulation of DUX4 in zygotes delays oocyte mRNA degradation but does not affect cell division. Interactions of 23 EGA-related transcription factors (TFs) with clusters of other TFs and chromatin modifier proteins form a network, helping to understand the regulation of EGA. To facilitate EGA research, 8-cell-like human cells were reprogrammed using a DUX4 expression pulse, providing a robust model for further studies.
Friday the 28th of March
鈥滵issecting the mammalian egg coat structure to unveil the block to polyspermy, understand infertility and developing non-hormonal contraception鈥
Chair of the webinar: Laia Torres Masd茅u.
The human zona pellucida (ZP) is made of proteins ZP1-4, which form heterofilaments that are essential for fertilisation. This talk introduced how ZP2 cleavage prevents polyspermy by altering the structure of the egg coat. Previously, ZP2 cleavage by ovastacin was thought to block sperm, but recent findings by Prof Luca Jovine鈥檚 group suggest it actually tightens and hardens the egg coat matrix, ensuring a permanent block to polyspermy. Structural studies conducted by Prof Jovine鈥檚 lab have revealed that the ZP filaments, thanks to the great abundance of cleaved ZP2, reorganise after fertilisation, compacting the ZP. Interestingly, mutations in ZP proteins have been related to infertility, and anti-ZP2 monoclonal antibodies have been seen to induce reversible infertility without disrupting the ovaries. These insights offer potential for non-hormonal birth control, as well as a better understanding of human infertility.
Tuesday the 22nd of April
鈥漈he Immunological Niche of the Intervillous Space in the Placenta鈥
Chair of the webinar: Sara Vikberg.
In this talk Docent Helen Kaipe discussed the interplay between the fetal placenta and the maternal immune system during pregnancy. Maternal blood flows through the intervillous space of the placenta from late first trimester to provide gas exchange, nutrients and antibodies to the fetus and to remove waste. The blood flows through the placenta in a shunted manner due to the tree-like structures of fetal placental tissue, leading to longer exposure of maternal circulating immune cells to the placental microenvironment. Helens group has shown that the immune cell composition in the blood that flows through the intervillous space of the placenta, intervillous blood, differs from that of the systemic circulation, with accumulation of certain immune cells. This suggests that the placenta creates a unique immunological niche. The group has also shown that the immune cell composition in the intervillous space is dynamic throughout gestation, adapting to the needs of different times of gestation and the growing fetus.
Thursday the 22nd of May
鈥滳ontraceptive use and abortions in Stockholm: trends and disparities鈥
Presenters: D茅siree Lichtenstein and Kyriaki Kosidou
Student Chair. Marika Rostvall
This presentation described findings from the VAL database, which includes healthcare data and linked registers. They examined contraception use and abortion trends from 2018鈥2022, focusing on sociodemographic differences. Each year during this period, 22-23% of women and girls collected contraceptives, with oral contraceptives being most common. Younger women and girls used less effective methods, despite having the highest use of contraception overall. Higher contraceptive use was seen among women and girls with higher income, education, and those born in Sweden. Abortion rates declined overall, especially among teenagers. However, rates remained highest in women aged 25鈥34 and were elevated in socioeconomically disadvantaged groups. Most abortions occurred before week 9 and often involved individuals not using contraception.
Tuesday the 10th of June
鈥漈issue-Specific Immune Dynamics in the Uterus: Insights from Endometrial NK Cells鈥
Student chair: Corinna Mayer
This presentation covered recent insights into uterine immune cell dynamics, with a focus on tissue-resident NK cells. The talk highlighted how endometrial regeneration drives IL-15鈥揹ependent NK cell differentiation and functional maturation. Data from monozygotic twins and uterus transplant recipients were presented to illustrate the influence of both genetic and environmental factors in shaping endometrial immunity. Findings from hematopoietic and solid organ transplantation showed full immune reconstitution within the uterus, emphasizing the organ鈥檚 capacity for immune integration. The seminar also explored NK cell recirculation patterns and mechanisms of tissue residency, offering new perspectives on immune regulation relevant to reproductive health and fertility.