Lecture 7: White blood cells

Question 1

Features of neutrophils?

Answer 1

• Large
• 90% granulocytes, 75% normal leucocytes
• dense nucleus with 2-5 lobes
• Granules in cytoplasm

Question 2

Granulocyte kinetics

Answer 2

• 7-10 day maturation in the marrow
• when released into blood circulate for 6-10 hours then –> tissues

Question 3

Regulation of granulopoiesis?

Answer 3

• Haematopoietic growth factors
  
  • IL3
  • stem cell factor
  • GM-CSF
  • G-CSF - used clinically in NZ

Question 4

Neutrophil function

Answer 4

1. Chemotaxis
2. Phagocytosis
3. Killing bacteria - oxidative and non oxidative

Question 5

Clinical relevance of neutrophils?

Answer 5

• Neutrophil leucocytosis
  
  • Featute of infection and inflammati
• Neutropenia
  
  • can be drug reaction (intended e.g cancer chemo or not)
• Neutrophil function defects - rare

Question 6

monocytes

Answer 6

• Much less common than neutrophils
• Bigger than neutrophils
• function:
  
  • once in tissue –> macrophages (different cells in different tissues)
  • Phagocytic (killing shit)
  • synthetic function –> inflammation response
  • Antigen presenting cells

Question 7

Clinical relevance of monocytes?

Answer 7

• Monocytosis
  
  • reactive - chronic infections e.g TB
  • Malignant - acute myeloid leukaemia

Question 8

Eosinophils

Answer 8

• Bilobed nucleus
• red/orange granules
• Clinical significance:
  
  • Allergic or hypersensitivity reactions
  • parasitic infestations

Question 9

Basophils

Answer 9

• Infrequent in blood
• Bilobed nucleus
• Deep blue granules
• IgE binding sites
• related to mast cells

Question 10

Lymphocytes

Answer 10

• Small mature cells
  
  • NK cells are larger with cytoplasmic granules
• Humoral immunity
• Differentiation occurs in primary lymphoid tissues
  
  • thymus
• After maturation in primary lymphoid organs –> 2ndary lymphoid organs
  
  • Lymph nodes
  • Spleen
  • Lymphoid tissue in gut
  • Bone marrow