Immune responses

Question 1

Innate responses

Answer 1

• Means ‘Born with’ or stays the same

Question 2

Immune system cells and functions

Hematopoietic stem cells

Answer 2

An immature cell that can develop into all types of blood cells, including white blood cells, red blood cells, and platelets.

Question 3

Immune system cells and functions

Monocyte

Answer 3

A naïve immune cell which can turn into other types of immune cell required macrophages

Question 4

Immune system cells and functions

Lymphocyte

Answer 4

There are two types of Lymphocyte: B and T cells.
There is also lymphocyte called natural killed cells (NK cells) which responds to virally infected cells and tumour cells.

Question 5

Immune system cells and functions

Neutophil

Answer 5

undertakes phagocytosis to remove pathagens

Question 6

Immune system cells and functions

Eosinophil

Answer 6

• A type of white blood cell
• A type of immune cell that has granules (small particles) with enzymes that are released during infections, allergic reactions, and asthma.

Question 7

Immune system cells and functions

Macrophage

Answer 7

• Mature monocytes
• Undertake phagocytosis and release cytokines to stimulate ongoing immune response

Question 8

Immune system cells and functions

Basophil

Answer 8

Defend against parasitic worms and ticks which are too large to be engulfed by neutrophils or macrophages

Question 9

The role of the lymphatic system

Answer 9

• It keeps body fluid levels in balance and defends the body against infections
• Part of the immune system

Question 10

Antibody mediated immune response (B-cells)

Antibody structure and function

Answer 10

Immunogolbulins (Ig). The five classes are: IgA, IgM, IgG, IgD, IgE

Question 11

Antibody mediated immune response (B-cells)

Neutralsation

Answer 11

Antibodies coat the pathagon and prevent iy from interact

Question 12

Antibody mediated immune response (B-cells)

Opsonisation

Answer 12

Coat the pathogen to attract and ancourage phagocytic cells

Question 13

Antibody mediated immune response (B-cells)

Complement fixation

Answer 13

Coat the pathogen to active blood proteins (complement) to kill the pathogen

Question 14

Cell mediated immune response (T- cells)

Answer 14

They activate specific B-cells to respond to infection and produce antibodies

Question 15

Cell mediated immune response (T- cells)

Helper T-Cells (CD8+)

Answer 15

Helper T-cells sense when there’s an infection in your body. They activate other immune cells to fight the infection.

Question 16

Cell mediated immune response (T- cells)

Memory T-Cells

Answer 16

They will trigger a faster and stronger immune response after encountering the same antigen.

Question 17

Cell mediated immune response (T- cells)

Regulatory T-Cells (CD8+)

Answer 17

Regulating or suppressing other cells in the immune system.

Question 18

Cell mediated immune response (T- cells)

Natural killer T-Cells

Answer 18

Modulates immune responses against infectious agents, autoantigens, tumors, tissue grafts and allergens.

Question 19

Active immunity + vaccination

Primary and secondary immune response

Answer 19

• Active immunity develops when someone is exposed to the actual disease- causing mirco-orgaism or to a vaccine
• Active immunity takes days or weeks to develop

Question 20

Passive immunity

Primary and secondary immune response

Answer 20

• Passive immunity occurs when a person is given antibodies against a pathogen or bacterial.
• Passive immmunity will work immeditely
• Passive immunity only lasts few weeks or months until the immunoglobulins disappear.
• A baby has passive immunity when its born through acquiring maternal antibodies through the placenta.

Question 21

Immune system cells and functions

Mast cells

Answer 21

Release histamine as part of the inflamatory responses

Question 22

Dendrictic cells

Answer 22

Antigen presentation to stimulate the adaptive immune response

Question 23

What are the three stages of acute inflammation

Answer 23

1. Release of inflammatory mediators
   - Cell derived caused by tissue damage: Histamine, prostaglandins, cytokines
2. Vascular response
   - Vasodilation occurs and increased blood vessel permeability
3. Cellular response
   - links to immune system, phaocytosis

Question 24

Explain the underlying pathophysiology of reduced oxygen levels as a result of sepsis.

Answer 24

• Imbalance between oxygen demand by the tissues and oxygen supply
• Compromised oxygen delivery due to combination of:
• Reduced blood pressure and flow
• Tissue oedema
• Adnoraml flow of blood through capillary bed
• Increased oxygen demand by the cells due to hypermetabolic state.