Micro Cytokines

Question 1

cytokines secreted by lymphocytes

Answer 1

Lymphokines

Question 2

cytokines secreted by monocytes/macrophages

Answer 2

Monokines

Question 3

chemotactic cytokines, involved in

inflammation

Answer 3

Chemokines

Question 4

secreted by leukocytes, act on leukocytes

Answer 4

Interleukins

Question 5

Property of cytokines:

Answer 5

1. Cytokines bind to specific receptors on target cell membranes, trigger signal-transduction pathways and alter gene expression
2. • Autocrine: cytokines act on the same cell its released from (Ex: IL2)
   • Paracrine: cytokines act on a nearby cell (most common)
   • Endocrine: cytokines goes into the circulation and bind to a distant cell
3. A single cytokine can have different effects
4. Different cytokines can have the same effect
5. Cytokines can work in synergy
6. The effect of one cytokine can inhibit another
7. Cytokines can network

Question 6

General Functions of cytokines:

Answer 6

Intercellular messenger molecules

1. Cellular & humoral immunity
2. Induction of inflammatory responses
3. Regulation of hematopoiesis
4. Cellular proliferation and differentiation
5. Growth inhibition, apoptosis
6. Wound healing

Question 7

Induction of Humoral Immunity:

Answer 7

1. Activation
2. Division
3. Differentiation

Question 8

Ags are Internalized, Processed and Presented by APC → MHC+Epitope complex is recognized by T cells → Specific Th cells become activated →

Answer 8

→Th1 → HELP for T cells → T cells activate other T
cells and macrophages
→Th2 →HELP for B cells → B cells produce antibodies

Question 9

Cytokines are: pro-inflammatory →

Answer 9

Act to make disease worse

IL-1, TNFa, IL-6

Question 10

Cytokines are: Anti-inflammatory →

Answer 10

Reduce inflammation and promote healing

IL-10, IL-4, TGF

Question 11

Regulation of hematopoiesis

Answer 11

Differentiation to different kinds of blood cells depends on the type of cytokine

Question 12

Immunopathological Reactions- Cytotoxicity

Answer 12

Cytotoxicity - when important cells are killed for example neurons can not be regenerated so when cytokines stimulate a macrophage to target an infected neuron this neuron is lost

Question 13

Immunopathological Reactions- Chronic Inflammation

Answer 13

Chronic Inflammation when the immune response does not stop because of continuous cytokine release and T cells activate macrophages causing joint damage as in rheumatoid arthritis Or when TNF causes cytotoxicity that kills the cells of pancreas causing diabetes

Question 14

Immunopathological Reactions- Granuloma

Answer 14

Granuloma happens when cell is not able to eliminate infection (like intracellular tuberculosis) and cells are attracted to surround the infected cell to stop the spread of bacteria, however if the granuloma becomes large it is harmful or when the granuloma happens in a place like the brain it it harmful

Question 15

Immunopathological Reactions- Excessive cytokine release

Answer 15

When the cytokines are released because of a an infection then spread through the blood circulation and affect different parts of the body and cause a multiple organ system failure