11.0 Immunology of Pregnancy

Question 1

What are Medwar’s ideas for why mother doesn’t ‘reject’ baby?

Answer 1

1) Immunological immaturity of fetus (not true)<br></br>2) Maternal immunosuppression (more like immunomodulation)<br></br>3) Placental barrier

Question 2

What are some pathogens that cross placenta?

Answer 2

<b>T</b>oxoplasmosis<br></br><b>O</b>thers = Listeria + Zika virus + Parvovirus<br></br><b>R</b>ubella<br></br><b>C</b>MV<br></br><b>H</b>IV/Hepatitis/Herpes<br></br><b>e</b><br></br><b>S</b>yphilis/Salmonella

Question 3

What percentage of embryos fail to implant?

Answer 3

70%

Question 4

What are the signs of pre-eclampsia?

Answer 4

1) HTN (170/110mmHg)<br></br>2) Proteinurea<br></br>3) Oedema

Question 5

What are the two sites of interaction between maternal immune cells and trophoblast:

Answer 5

<b>1) Maternal blood is in contact with syncytium (systemic immunity)</b><br></br>- Syncytiotrophoblast cells do not express MHC Class I or II (therefore evade immune recognition)<br></br><br></br><b>2) Invading trophoblast is in contact with immune cells (local immunity)</b><br></br>- Lymphocytes/Macrophages/Uterine NK cells

Question 6

What sequelae can occur if trophoblast invasion is not controlled?

Answer 6

1) Placenta accreta<br></br>2) Ectopic pregnancy

Question 7

What ligands are expressed on EVT?

Answer 7

HLA-C<br></br>- Polymorphic<br></br>- Varies from pregnancy to pregnancy<br></br><br></br><b>HLA-E</b> - monomorphic<br></br><b>HLA-G</b> - monomorphic

Question 8

What is the main leukocyte found in the decidua?

Answer 8

<b>NK cells</b><br></br>- They can mediate direct contact with EVT cells

Question 9

What receptors are found on NK cells?

Answer 9

<b>1) KIR</b><br></br>2) NKG2A/CD94<br></br>3) LILRB1

Question 10

What chromosome is the HLA-C locus found on?

Answer 10

Chromosome 6

Question 11

What are the two groups for HLA-C?

Answer 11

C1 - No problems<br></br><br></br>C2- can cause inhibition of NK cell function if interacts with KIR haplotype A

Question 12

What chromosome is the KIR locus found on?

Answer 12

Chromosome 19

Question 13

What are the two groups for KIR?

Answer 13

<b>Haplotype A</b><br></br>- Can only respond to HLA-C with inhibition<br></br>- Haplotype A + C2 = problems (PE/FGR/RM)<br></br><br></br><b>Haplotype B</b><br></br>- Protective when interacting with C2

Question 14

Draw a table of KIR- HLA-C interactions:

Answer 14

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