Honours Project Book - Faculty of Health Sciences - University of ...

will be analysed by computer-assisted histological
and morphometric analysis at key milestones in
development, and quantitative RT-PCR based
analysis of mRNA expression for placental genes
implicated in development and function. Fetal tissue
will be genotyped by diagnostic PCR and growth
and survival rates of progeny of different genotypes
will be determined. The potential contribution of
TGFβ1 in immune-mediated placental dysfunction will
be analysed by assessing Treg cells, which are
implicated in maternal immune tolerance of the
conceptus. The results will provide a better
understanding of the physiological role of TGFβ1 in
establishing and maintaining pregnancy, and will
inform upon the possible contribution of gene
polymorphisms in TGFβ1, or other environmental
perturbations in TGFβ1, in infertility and pathologies of
human pregnancy.
Keywords
Placenta / cytokines / TGFβ
PROJECT: (Basic) Can macrophages aid embryo
implantation for pregnancy success?
.R. O&G.
Supervisor
Professor Sarah Robertson
Introduction to the laboratory
To implant and establish the connections that are
vital for further development, the early embryo must
attach to and then breech the barrier posed by the
epithelium of the maternal reproductive tract (Figure
1).
Infertility, miscarriage, and other pathologies of
pregnancy stemming from ‘shallow’ placental
development are known to have their origins at the
time of embryo implantation into the uterus.
However the biological process of embryo
implantation is not understood.
While it is clear that precisely regulated changes in a
wide array of parameters including glycosylated
proteins are associated with achieving a receptive
state for embryo implantation (‘window of
implantation’), how these changes occur remains to
be clarified.
Macrophages are particularly prominent amongst
the large and dynamic population of inflammatory
cells that traffic through the uterus and are able to
secrete an array of potent regulatory molecules.
Figure 1. Epithelial cells stained with lectin in mouse
uterus (MJJ)
Their recruitment, differentiation and state of
activation fluctuate over the course of the oestrous
cycle and particularly during early pregnancy, under
the direction of potent local determinants including
cytokines and chemokines, and components of the
extracellular matrix (ECM). Amongst these regulators
of uterine macrophages, our interest has centred on
the role of seminal fluid, which acts at the time of
insemination to elicit a rapid and dramatic influx of
macrophages and other activated inflammatory
cells into the female reproductive tract (Figure 2).
The success and quality of pregnancy is
compromised if macrophage populations are
disrupted in females by preventing exposure to
seminal plasma. When the seminal vesicle is
surgically removed from rodents implantation rates
are reduced, and fetuses have a high incidence of
growth retardation secondary to changes in
placental development. We have postulated that
the inflammatory cells recruited during the response
to seminal plasma exposure might impact on uterine
receptivity, particularly the glycobiology of the
epithelium associated with pregnancy success.
The student will develop specialised knowledge of
the implantation process and early pregnancy. In
addition, they will develop skills in real-time RT-PCR,
immunohistochemistry and protein blotting.
Hypothesis
1. Successful embryo implantation is dependent on
communication between uterine macrophages and
luminal epithelial cells in the uterus during early
pregnancy.
2. Morphological and biochemical changes
associated with epithelial cell receptivity, including
their adhesive properties are regulated by paracrine
and juxacrine signals of macrophage origin.
3. Reduced abundance or altered functional
phenotype in endometrial macrophages during the
peri-implantation phase of pregnancy impairs
embryo implantation and placental morphogenesis,
with adverse consequences for fetal development
and health after birth.
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