Overview on Inflammation and Innate IS

Question 1

What is the composition of blood?

Answer 1

Its made up of plasma (water, ions, plasma proteins and substances transported by blood) and cellular elements.

Question 2

How does one aquire serum?

Answer 2

Cells, platets and coagulation factors are removed. Remove any clots formed in a tube

Question 3

Define the lymphatic system

Answer 3

The lymphatic system takes care of lymph liquid which is distributed throughout the body. There are 2 lymphoid organs; Primary and Secondary. The primary lymphoid organs are the bone marrow and thymus. the secondary lymphoid organ are lymph nodes, spleen, Mucosa ALT and Gut ALT.
(Transportation of white blood cells)

Question 4

Where do blood cells derive from?

Answer 4

hematopoeitic stem cells in the bone marrow

Question 5

Macrophages and Neutrophils both are myeloid cells in the Innate system, what is their shared function and what differentiates them?

Answer 5

Its activated function is phagocytosis and bactericidical mechanisms. The difference is that macrophages produces cytokines at a much higher rate.

Question 6

Eosinophil function

Answer 6

Killing of antibody coated parasites

Question 7

basophile function

Answer 7

promotes allergic responses and augumentation of anti-parasitic immunity

Question 8

Mast cell function

Answer 8

Release of granules containing histamine and active agents

Question 9

3 important functions of the innate IS

Answer 9

1. Provides a first line of defense in order to avoid and/or eliminate microbes
2. Stimulates and effects the adaptive IS to elecit an optimized effect
3. Provide strong effector mechanisms, that could often also be used by the adaptive system

Question 10

4 components of the Innate IS

Answer 10

1. Phagocytosis and killing of microbes
2. Lysis of infected cells via NK-cells
3. Cytokines released from macrophage activation leads to inflammation via neutrophils
4. Activation of the complement system

Question 11

What are the 4 symptoms of inflammation and how are they caused?

Answer 11

• Heat, Redness - Redness and heat are caused by an increased blood flow (leukocyte recruitment) to
  the inflamed area.
• Swelling – TNF-alfa causes vasodilation and vascular leakage, of example plasma protein albumin. This alters the osmotic pressure and causes water content to increase, which results in swelling.
• Pain - TFN-alfa & IL-1beta causes inflammatory cells to migrate into tissue and releases inflammatory mediators that cause pain.
• Loss of function is the combination of the effects that cause pain and swelling

Question 12

What are the 3 types of inflammation?

Answer 12

Acute Inflammation, Hypersensitivity reactions, and Chronic inflammations

Question 13

What is acute inflammation?

Answer 13

Its the accumulation of neutrophil granulocytes and leakage of plasma through the blood vessel wall. usually caused by bacteria

Question 14

What is chronic inflammation?

Answer 14

Accumulation of macrophages, lymphocytes and plasma cells and often fibrosis covers it

Question 15

What is the process called when blood cells pass through the intact walls of the capillaries?

Answer 15

Diapedesis

Question 16

What are the cell adhesion molecules CAMs that regulate cell trafficking or diapedesis?

Answer 16

Selectins, Integrins and Immunoglobulin-superfamily

Question 17

What are selectins typically known for?

Answer 17

Typical for leukocyte-blood vessel wall
interactions and leukocyte-platelet
interactions.

Question 18

Once the endothelium is activated via inflammatory mediators, how does the selectins on the membrane interact with passing leukocytes?

Answer 18

P-selectins interact with the L-selectins of the leukocytes. E-selectins forms a weak adhesion to the carbohydrate chains (on the mucin), which allows the leukocyte to roll along the endothelial wall.

Question 19

What are integerins typically known for?

Answer 19

Interacts with intercellular CAMs (ICAM, Ig-super
family) or motifs of the extracellular matrix and mediates firm cell-cell/extracellular matrix adhesions.

Question 20

Explain integrin adhesion in 3 steps

Answer 20

1) The leukocyte is activated and expresses β2-integrins and the activated endothelium express ICAM.

2) Integrin binds firmly to ICAM and the L -selectins are
shed.

3) Integrins aid in diapedesis so the leukocyte can migrate into the tissue

Question 21

What main chemoattractant guides the leukocyte to a site of infection?

Answer 21

IL-8 gradient

Question 22

Briefly define the concept of inflammation. What is the overall benefit?

Answer 22

Local accumulation of fluid, plasma proteins and white blood cells that is initiated by physical injury, infection, or a local immune response. Inflammation localizes/direct the immune system, limit the infection, and stimulate healing of tissue.

Question 23

Explain 4 phases of a typical sequence in which a neutrophil granulocyte is recruited out of the blood circulation to the site of infection in a tissue during acute inflammation.

Answer 23

1. Endothelium is activated by inflammatory mediators e.g., TNF(secreted from macrophage).
   P-selectins interact with the L-selectins of the leukocytes. E-selectins forms a weak adhesion to the carbohydrate chains (on the mucin), which allows the leukocyte to roll along the endothelial wall.
2. CXCL8R expressed on neutrophil binds to chemokine CXCL8 secreted from macrophage that first encountered the antigen activates the neutrophil. The activated neutrophil expresses β2-integrins which binds to ICAM on activated endothelium and cause firm adhesion. Selectins are shed.
3. Integrins aid in opening up space between adjacent epithelial cells and allow neutrophil to migrate into the tissue(diapedesis). CXCL8 and other chemoattractant guide the leukocyte to the site of infection by chemotaxis.
4. Phagocytosis of microbes and foreign material.

Question 24

What is the main difference between the innate and adaptive immune system?

Answer 24

The main difference between the innate and adaptive system is:

• The innate system acts faster in
  immune response and does not have specificity or memory as the adaptive immune system has.

The systems are dependent on each other. Dendritic cells(innate) activate T-cells(adaptive). Chemokines and cytokines are used by both immune systems.