Molecular aspects of implantation Flashcards
Endometrium changes - proliferative stage (2)
Small glands with epithelial cells close together
Dense stroma
Endometrium changes - early secretory phase (2)
Glands expansing
Secretory vesicles at basal side of epithelial cells
Endometrium changes - mid secretory phase (3)
Further expansion of glands
Secretory vesicles at apical she of epithelial cells
Secreted material into lumen
Endometrium changes - late secretory phase (3)
Long extended glands
No secretory vesicles
Oedema in stroma
Where are steroid hormone receptors expressed?
Nuclei and storm of epithelial cells
When is oestrogen receptor maximum expression?
Late proliferative/early secretory phase
What is progesterone receptor maximum expression?
Early secretory phase
In which cells do progesterone receptors disease in first?
Epithelial before stroma
What type of leucocyte is not in the endometrial stroma?
B cells
What are two abnormalities of endometrial function?
RIF
Recurrent miscarriage
What is the window of implantation?
Endometrium receptive to embryo
Days 20-23
Give 2 moleculs involved in the control of implantation
Proteases
Adhesion molecules (integrins)
Cytokines
Give 3 types of trophoblast and their roles
Syncytiotrophoblast - formed inside blood vessles
Extra-villus - invasive, anchoring
Endovascular - invades blood vessels
What is decidualisation controlled by? (2)
cAMP
Progesterone
What is MMP enzyme activity controlled by? (2)
Expression of actual protein
Pro-MMP (trypsin and plasmin)
TIMPs inhibit
What is the production of MMPs controlled by? (3)
Progesterone (decreases)
IL-1, TNFα
hCG
What are the roles of proteases in endometrial function? (2)
Implantation - break down of ECM
Menstruation - break down of endometrial tissue
Which integrins are cyclically expressed in the endometrium?
αvβ3
α1
α4
Where are cytokines expressed? (2)
Pregnant - decidual and epithelial cells
Non-pregnant - epithelial cells
Which Th is pregnancy bias towards?
Th2
Which cytokines are important for implantation? (2)
IL-11
LIF
What are 2 molecular tools/technologies?
Endometrial transcriptomics
Endometrial receptivity array
Define recurrent implantation failure
No pregnancy after transfer of at least 3 good quality embryos
Which intern may be involved in attachment?
αvβ3
