8- Immune system 1

Question 1

4 elements in second line of defense

Answer 1

Interferons​
Complement system ​
Iron-binding proteins​
Antimicrobial proteins

Question 2

what are interferons and what do they do?

Answer 2

a protein produced by lymphocytes, macrophages, and fibroblasts that have been infected with viruses

interfere to stop the virus replicating

Question 3

what is the complement system?

Answer 3

a group of about 30 inactive proteins present in blood plasma and on plasma membranes​ which, when activated, “complement” or enhance certain immune, allergic, and inflammatory reactions

Question 4

4 iron-binding proteins

Answer 4

Transferrin - in blood and tissue fluids ​

Lactoferrin - in milk, saliva, and mucus ​

Ferritin - in the liver, spleen, and red bone marrow
​
Haemoglobin - in red blood cells​

Question 5

what do Antimicrobial Proteins (AMPs) do?

Answer 5

Antimicrobial Proteins (AMPs) have broad-spectrum antimicrobial activities and attract dendritic cells and mast cells

Question 6

3 types of Antimicrobial proteins (AMPs)

Answer 6

Dermicidin - produced by sweat glands​

Defensins and cathelicidins - produced by neutrophils, macrophages, and epithelia​

Thrombocidin - produced by platelets​

Question 7

what do natural killer (NK) cells do?

Answer 7

Natural killer cells kill infected cells and release microbes to be destroyed by phagocytes
(assassins)

Question 8

analogy for phagocytes?

Answer 8

Phagocytes are the living garbage trucks of your body, with their main role being to ingest microbes or other particles such as cellular debris

Question 9

2 types of phagocyte?

Answer 9

Neutrophils ​

Macrophages (developed from monocytes)​ - fixed and wandering macrophages

Question 10

5 stages of phagocytosis?

Answer 10

1- chemotaxis
movement of phagocytes to a site of damage​

2- adherence
attachment of the phagocyte to the microbe or other foreign material​

3- ingestion
process of engulfing the microbe​ vis pseudopods

4- digestion
by lysozymes, other digestive enzymes and lethal oxidants

5- killing

Question 11

4 evasions of phagocytes?

Answer 11

• capsule formation ​
• toxin production​
• interference with lysozyme secretion
• microbe’s ability to counter oxidants produced by the phagocytes

Question 12

3 stages of inflammation?

Answer 12

1- vasodilation
2- emigration
3- tissue repair

Question 13

what is the third line of defence?

Answer 13

adaptive (specific) immunity

B and T cells

Question 14

what is specific immunity?

Answer 14

the ability of the body to defend itself against specific invading agents such as bacteria, toxins, viruses, and foreign tissues

Question 15

2 types of specific immunity?

Answer 15

Antibody-Mediated Immunity (AMI) / Humoral Immunity​

Cell-Mediated Immunity (CMI)​

Question 16

What is cell-mediated immunity (CMI)?

Answer 16

CMI refers to destruction of antigens by T cells

Question 17

What is antibody-mediated (humoral) immunity (AMI)?

Answer 17

Destruction of extracellular antigens by antibodies.

Antibodies are like little homing missiles that are formed when B cells transform into plasma