Immunity of the placenta and newborns

This protocol will entail two different projects. The first project (1)
investigates the effects of immunosuppressive drugs on immune cells of the
placenta, cord blood, and peripheral maternal blood during pregnancy and
postnatally. The second project (2) investigates the innate immune response of
newborns.

1. Investigation of the effect of immunosuppressive drugs on placental derived
mononuclear cells, peripheral blood derived mononuclear cells during pregnancy
and postnatally, and cord blood derived mononuclear cells

It is now well accepted that the immune system plays an important role in the
implantation of the developing semi-allogeneic embryo into the wall of the
maternal uterus. The immune system has to balance the opposing needs of
maintaining robust immune reactivity to protect both mother and fetus from
invading pathogens, while at the same time tolerating highly immunogenic
paternal alloantigens in order to sustain fetal integrity. In fertile women the
endometrium prepares every month for potential pregnancy. In the final part of
the menstrual cycle there is a huge influx of maternal leucocytes, including a
high percentage of NK cells. These uterine NK cells (uNK) direct placentation by
controlling trophoblast invasion and regulatory T cells are responsible for the
establishment of tolerance by modulating the immune response. A variety of
other cell types, including decidual stromal cells, dendritic cells, and
immunomodulatory multipotent mesenchymal stromal cells, are found at the fetal*
maternal interface. These cells conspire to establish a suitable environment
for fetal development without compromising systemic immunity. Defects in any of
these components can lead to gestational failure despite successful
fertilization. Since immunosuppressive drugs can affect immune cells, they are
likely to affect immune cells at the fetal-maternal interface with subsequent
complications for pregnancy such as preeclampsia, preterm delivery and fetal
growth restriction.
These complications are commonly observed in renal transplant patients. Here we
will investigate the in vitro effect of different immunosuppressive drugs on
placental derived mononuclear cells from healthy pregnant women. The in vivo
effects of immunosuppressive medication will be studied by obtaining the
placenta of pregnant kidney transplant patients. Also, the effects of the use
of immunosuppressive drugs, such as calcineurin inhibitors and azathioprine, in
these pregnant patients may be visible in the peripheral blood compartment and
neonatal blood compartment. Therefore, we will also study the in vivo effect of
these drugs on maternal peripheral blood derived mononuclear cells taken at
each trimester during pregnancy (*8-13 weeks, *25 weeks of pregnancy, around
labor (*36-40 weeks), and 8-10 weeks postnatally) and on cord blood derived
mononuclear cells. The results will improve our insights on the risks of
immunosuppressive drugs on pregnancy in renal transplant patients and on their
offspring.

2. Investigation of the innate immune response of newborns:

The development of the immune system takes place in the first months of life
during which infants are particularly vulnerable to viral and bacterial
infectious diseases. The introduction of the national vaccination program
significantly reduced the burden of infectious diseases in the pediatric
population. However, young infants are still susceptible to infectious due to
the fact that most vaccines are administered after 2 months. Secondly, for many
pathogens there is currently a lack of (optimal) vaccines. A small percentage
of all infants develop a severe infection and require hospitalization and/or
mechanical ventilation. The exact mechanisms of the susceptibility to develop a
severe infection are yet to be elucidated. In this context, collection of cord
blood will allow investigation of the neonatal immune response. Better
understanding of the neonatal immune response will proof useful in elucidating
the pathogenesis of infectious diseases.

1. To investigate the influence of different immunosuppressive drugs on the
immune response of placental derived mononuclear cells, peripheral blood
derived mononuclear cells, and cord blood derived mononuclear cells.

2. To investigate the neonatal immune response against a variety of pathogens
and compare this with the adult immune response

This is an in vitro study to investigate (1) the effects of immunosuppressive
drugs on immune cells of the placenta, maternal peripheral blood, and cord
blood, and (2) the neonatal immune response against a variety of pathogens.
This study will be coordinated by the Laboratory of Pediatric Infectious
Diseases at the Department of Pediatrics of the Radboud University Medical
Center and the Laboratory of Medical Immunology at the Radboud University
Medical Center.

Pregnant women who attend the Department of Gynaecology and Obstetrics of the
Radboud University Medical Center will be included in the study. The physician
determines whether the pregnant women are eligible to be included in the study
and will inform the subjects about the study.
After informed consent, the placenta will be taken immediately after the
caesarean section. The amount of cord blood taken will usually vary between 10
en 200 ml of blood depending on the size of the placenta. The placenta will be
placed in a tray and 500 ml of cold PBS will be added for preservation.
For the renal transplant patients and some healthy controls, collection of
maternal blood in EDTA tubes (at gestational week 8-13, week 24, at term
pregnancy (*36-40 weeks), and 8-10 weeks postnatally) will be planned during
regular visits to the hospital and at delivery, and if possible with regular
patient care collection. A case record form is used to gather information about
medical history, gestational age and use of immunosuppressive medication.

In this study, peripheral blood, placenta tissue and blood from the placenta
will be used. There are no direct benefits of this study for the participating
subjects. The benefits may be related to the future understanding of effects of
immunosuppressive drugs on the maternal immune system and placenta and future
understanding neonatal immune responses. Because peripheral blood will be
collected during a regular visit to the clinic and only the placenta is used in
this process, there is no direct risk to the subject.