Blood

Question 1

What are most blood cells derived from? Where from?

Answer 1

Multipotential haemopoietic stem cells from bone marrow.

Question 2

What are the 2 blood cell groups haemopoietic stem cells differentiate into? Which cell groups do these then different into?

Answer 2

Lymphoid - to lymphocytes

Myeloid - to RBCs, other WBCs

Question 3

What is the role of platelets? what are they formed from? Where are they broken down in the body?

Answer 3

“Repair” - Initial plug for clotting, surface for clotting factors, involved in initiation of clotting cascade. Broken down in the spleen

Question 4

What are the main roles of the ‘granulocyte’ WBCs neutrophils, basophils, eosinophils and mast cells

Answer 4

Neutrophils - initial inflammation (innate immunity)
Basophils - allergic response IgE, release Histamine
Eosinophils - allergic response IgE
Mast cells - similar to basophils

Question 5

What are the 4 types of ‘granulocyte’

Answer 5

Neutrophils, basophils, eosinophils, mast cells

Question 6

What are 6 types of mononuclear WBC?

Answer 6

monocytes
macrophages
dendritic cells
T cells
B cells
NK cells

Question 7

What are dendritic cells derived from? What are their two main roles?

Answer 7

Monocytes

Phagocytose and APCs

Question 8

What 4 hormones/cytokines act to stimulate haematopoiesis and which cells do they stimulate?

Answer 8

Erythropoetin - stimulates RBCs
Thrombopoetin - stimulates plalelet productions
Interleukins stimulate T/B cells
G-CSF - stimulates granulocytes

Question 9

How long to RBCs circulate for?

Answer 9

around 120 days

Question 10

How is structure (4) of RBC suited to function?

Answer 10

No nucleus
No organelles
Biconcave
Lipid bilayer

Maximise O2 Hb CO2 carrying space and flexible to fit through capillaries

Question 11

Name 4 phagocytes of WBCs

Answer 11

Neutrophils
Eosinophils
Basophils
Monocytes/macrophages

Question 12

Can macrophages move?

Answer 12

Yes chemotaxis towards organisms

Question 13

What do NK cells do

Answer 13

Stimulate cells to undergo apoptosis - adaptive immunity

Question 14

What could recombinant growth factors be used for

Answer 14

e.g. post cancer neutropenia helps regenerate blood cells

Question 15

Where are reasons for a too high blood count

Answer 15

Thrombocythemia
Polycythemia
Leukemia

Question 16

What are reasons for low blood count

Answer 16

Anaemia
Leucopenia
Thrombocytopenia

Question 17

What is pancytopenia

Answer 17

Low count of all blood cells

Question 18

What is a common reason for change in Full Blood Count test results

Answer 18

Something has been reacted to e.g. infection

Question 19

How might you get a sample to look at bone marrow dysfunction?

Answer 19

Take bone marrow biopsy

Question 20

How can a translocation cause Leukemia? How can you treat this?

Answer 20

Reciprocal translocation e.g. of chromosome 22 (Philadelphia chromosome) can lead to a fusion gene which causes tyrosine kinase to be constantly ON leading to constant cell prolif = cancer. Imatinib is a tyrosine kinase inhibitor acts to kill cancer cells by blocking tyrosine kinase

Question 21

What is the role of tyrosine kinase in normal cells?

Answer 21

On/Off for cell function e.g. proliferation

Question 22

Which blood cell plays a huge role in autoimmune disease and rejection of transplant?

Answer 22

T cells