Immunology of pregnancy Flashcards
What two cells can be alloreactive in pregnancy? And differences?
t cells (clonally distributed receptor) somatic gene rearrangement. NK cells, polymorphic germ line encoded NK receptors, highly variable and inherited from parents.
What cells types are found within the dcidula mucosa
glands (secrete uterine milk), stromal cells and also many cells of the innate immune system.
70% are unique NK cells, others include macrophages, some DCs, and can be variable amounts of T cells and very few B cells.
What forms first? Placenta or embryo? Which is in contact with the mother and their immune system?
placental forms first and placenta, NOT foetus is in contact with the mother
What are the main cells of the placenta? What two types are there?
Placental trophoblasts are in contact with mother. Two types, the villous trophoblasts and extravillous trophoblasts.
Role of villous (synctiotrophoblast) trophoblasts?
help embed and form villi in the decidua mucosa. They are surrounded by maternal blood for transfer of nutrients and gases into the syncytium.
Produce hormones and proteins.
Barrier for microbes.
Role of extravillous torphoblasts.
Anchor placenta to uterus.
Invade deep into the decidua and as far as the myometrium, where they will destroy smooth muscle layer of arteries to transform spiral arteries.
This means these arteries can’t do vasoconstriction, which increases blood flow to the uterus and for baby.
Do all mammals have discoidal placentas?
No, only humans and primates (and rats) have discoidal placenta. Other mammals its different, makes it harder to study humnas.
when might you get exhcnage of foetal cells?
When foteal cells (blood cells) cross back into mother. Might have antiboides formed against baby rhesus antigen.
Do extravillous trophoblasts keep proliferating?
No. (unlike invading cancer cells).
What diesease are associated with the prohibited and reduced invasion of the extravillous cells?
Like pre-eclampsia (early and late onset) and recurrent miscarriages, not enough blood flow to the baby.
Fetal growth restriction and still birth.
What happens to blood flow and villi when trophoblast transformation of spiral arteries inhibited?
Short bursts of high blood flow, and villi don’t form properly.
What happens when trophoblast invasion doesn’t stop?
if it goes past myometrium and further (accreta, increta, percreta), the muscousal lining is absent .
After C-section, this can happen as myometrium which has become scar tissue. Or maybe its the lack of decidua that causes problems (like ectopic pregnancy)
What are the two funcitons of the decidua immune system?
To prevent t cell allogeneric rejection and regulate trohpoblast invasion.
What hints might indicate the immune system is important in pre-eclampsia?
70% of the time preeclampsia occurs in the first pregnancy, risk decreases after that. Risk is increased to that of first pregnancy with the change of partner?
surrogacy, the risk is higher, where the embryo is entirely non-self.
What structure is important for maintiaing the decidua and placental lining?
corpus luteum, which produces progesterone.
