Leucocytes and Inflammation Flashcards Preview

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Flashcards in Leucocytes and Inflammation Deck (17)
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1
Q

What is Haematopeosis?

What is Leucopoeisis? (2)

A
  1. Production of Blood cells

2. Production of Leucocytes

2
Q

Where does Leucocyte formation start? (2)

A

From Pluripotent hematopoietic stem cell in the bone marrow.

3
Q

What are the 2 major leucocyte lineages, what type of leucocytes do they form? What is the other minor lineage? (3)

A

In the bone marrow, the hematopoietic stem cell Divides into:

Major:

  1. Lymphoid Progeny - Form Lymphocytes, small and bland-looking.
  2. Myeloid Progeny - Form granulocytes, larger cells with cytoplasmic granules.

Minor:
3. Immature dendritic cell - Forms mature dendritic cell in tissue.

4
Q

What are the types of lymphocytes? (3)

A

In the blood:

  1. B cells (becomes Plasma Cell when activated)
  2. T cells
  3. Natural Killer Cells

These then move into Lymph nodes.

5
Q

What are the types of granulocytes? (5)

A
  1. Neutrophil
  2. Eosinophil
  3. Basophil
  4. Monocyte (forms Macrophage in tissues)
  5. Unknown Precursor of Mast cell (forms mast cell in tissues)
6
Q

What are the functions of Dendritic cell? (2)

A

Dendritic cells recognise antigens in peripheral sites of the lymph nodes, presenting them to adaptive immune cells (e.g lymphocytes) to activate.

7
Q

What are the functions of:

  1. Neutrophils
  2. Eosinophils
  3. Basophils
  4. Macrophages
  5. Mast Cells (5)
A
  1. Neutrophils - Phagocytosis and activation of antibacterial mechanisms.
  2. Eosinophils - Killing of antibody-coated parasites
  3. Basophils - Unknown
  4. Macrophages - recognise antigens, activating phagocytosis and other antibacterial mechanisms.
  5. Mast Cells - Release of granules containing histamine and other active agents.
8
Q

What are the functions of:

  1. B-cell
  2. T-cells
  3. NK Cells
A
  1. B-cells - Produce antibodies. These antibodies bind to antigens such as Bacteria.
  2. T-cells - Mature in thymus gland during gestation. CD8 cells deal with intracellular (viral) infection. CD4 (helper) cells are required in direct immune activity.
  3. NK cells - Important with intracellular infection and tumours.
9
Q

What are Cytokines? (1)

A

Cytokines (interleukins) are small proteins released by cells to communicate to other cells e.g immune cells.

10
Q

What are Chemokines? (2)

A

Chemokines are small proteins released by cells to guide other cells on where they should go e.g CXCL8 guides neutrophils to site of infection.

11
Q

What is the mechanism of action of phagocytosis? (3)

A
  1. Phagocyte receptors recognise microorganism antigen.
  2. Microorganism is engulfed and release lysosomes which contains digestive enzymes.
  3. Microorganism killed in ‘phagolysosome’ by low pH, digestive enzymes, toxic-free radicals and hydrogen-oxygen products.
12
Q

What processes does local inflammation activate? (3)

A

It activates action of

  1. Phagocytes;
  2. Release of soluble mediators:
    * Cytokines - (TNF alpha), IL-1, IL 6.
    * Chemokines: CXCL8
13
Q

What can increased action of Cytokines and Chemokines when released by macrophages at an infection site do to blood vessels? (3)

A
  1. Vasodilation
  2. Increased Permeability
  3. Increased adhesion molecules on blood vessel endothelium.
14
Q

Outline how the symptoms of inflammation manifest due to action of Cytokines and Chemokines? (2)

A
  1. Redness, heat and swelling is caused by increased vascular permeability and vasodilation.
  2. Pain is caused by inflammatory cells (e.g neutrophils) entering tissue and releasing inflammatory mediators.
15
Q

What feature of the immune system causes systematic inflammation? (2)

A

Cytokines, as these act on distant tissues and are released into circulation.

16
Q

What are the good things about inflammation? (3)

A
  1. Amplifies Immune response
  2. Focuses the immune response using chemokines and cytokines
  3. Activates next stage of immunity (B cells/Tcells)
17
Q

What are the bad things about inflammation? (3)

A
  1. Can incorrectly activate immune response when no infection present.
  2. Can damage healthy tissue
  3. Can activate immune response in uncontrolled manner (septic shock)