Immunology

Question 1

Immunology

Answer 1

The study of defence mechanisms of the organism

Question 2

Immunity

Answer 2

Protection from disease and specifically infectious disease

Question 3

What are the 5 distinct characteristics of inflammation

Answer 3

• Heat
• Pain
• Swelling
• Redness
• Loss of function of the part of the body infected

Question 4

What should the immune system be able to do?

Answer 4

• Discriminate between cells and pathogens, and harmful and harmless non-self entities
• Be flexible
• Manage infection - recognise the pathogen and provide protection against it
• Memory - produce antibodies which remain in the blood

Question 5

Chronic inflammation

Answer 5

Inflammation occurring even after elimination of the pathogen

Question 6

Autoimmune disease

Answer 6

immune system attacking non-harmful, self entities

Question 7

Immunodeficiency

Answer 7

immune system does not work at all and does not recognise harmful, non-self entities

Question 8

What are pattern recognition receptors?

Answer 8

Toll-like receptors that recognise PAMPs and DAMPs

Question 9

Describe the structure of TLR

Answer 9

• type I transmembrane proteins containing:
  ectodomain containing leucine repeats - mediate PAMP recognition
  transmembrane domain
  cytosolic TIR domains - activate downstream signalling pathways

Question 10

What are the membrane-bound PRRs?

Answer 10

Toll-like receptors

C-type lectin receptors (CLRs)

Question 11

What are the cytoplasmic PRRs?

Answer 11

NOD-like receptors (NLRs)

RIG-I-like receptors (RLRs)

Question 12

TLRs in the cell recognise….

Answer 12

nucleic acids from the bacteria or viruses that enter the host cell

Question 13

TLRs on the cell membrane recognise….

Answer 13

bacteria, fungi and yeast parts

Question 14

Which TLR works without MYD88 and which adaptor protein does it recruit?

Answer 14

TLR3

recruits TRIF

Question 15

Which TLR works with and without MYD88?

Answer 15

TLR4

Question 16

TLR expression in the FRT

Answer 16

TLRs are expressed in all epithelial cells of the FRT
Vaginal cells lack TLR4 expression because TLR4 recognises bacterial PAMPs. This prevents a constant immune response against the bacteria existing in the vagina.

Question 17

Which TLRs are not expressed in humans?

Answer 17

TLR11 and TLR10

Question 18

Which phase of the menstrual cycle is TLR expression the highest?

Answer 18

Secretory phase - FRT gets ready for the possibility of embryo implantation –> lining of the endometrium thickens

Question 19

How does progesterone regulate immunity in the FRT?

Answer 19

progesterone increases TLR expression on the epithelial cells, providing the tract for possible implantation

Question 20

Describe the immune system response during menstruation.

Answer 20

• Macrophages and neutrophils clear the disrupted endometrium and produce MMPs which break down the connective tissue of the endometrium
• TIMPs are also produced to regulate the action of MMPs, ensuring not too much is broken down

Question 21

Describe inflammation during implantation

Answer 21

Human decidua contains lots of macrophages, NK cells and regulatory T cells
Dendritic cells, NK cells and macrophages infiltrate the decidua and accumulate around the invading embryo

Question 22

Immune Tolerance

Answer 22

how the immune system reduces the negative impact of the pathogen on an individual without actually fighting pathogens