WBCs

Question 1

types of phagocytes

Answer 1

granulocytes

• neutrophils
• basophils
• eosinophils

monocytes

Question 2

regulation of neutrophils

Answer 2

haematopoietic growth factors

e.g. IL3, stem cell factor, G-CSF

Question 3

life cycle of neutrophils

Answer 3

• from marrow haematopoietic stem cell –> myeloblast
• 7-10 day maturation in marrow
• circulates 6-10 hours, then into tissues to phagocytose

Question 4

clinical importance of G-CSF

Answer 4

filgrastin

- target given to patients having chemotherapy to reduce neutropenia

Question 5

function of neutrophils

Answer 5

• chemotaxis to sites of damage, infection
• phagocytosis of foreign antigens
• destruction of bacteria by oxidative and non-oxidative means

Question 6

monocyte life cycle

Answer 6

• shares precursors with neutrophils
• 7-10 day maturation in marrow
• 1-3 days circulating in blood
• enters tissue = macrophage
  
  • liver = kupffer cells
  • lung = alveolar cells
  • skin = langerhans cells

Question 7

function of monocytes

Answer 7

mainly seen in chronic infections

phagocytosis

• chemotaxis to site
• opsonisation
• phagocytosis

Question 8

synthetic function of monocytes

Answer 8

• complement
• interferons
• cytokines (TNF, IL-1)
• growth factors
• PG

as well as antigen presentation

Question 9

structure and function of basophils

Answer 9

• IgE binding sites
• related to mast cells
• contain histamine granules
• induces features of allergy, hypersensitivity reactions

Question 10

different functions of lymphocytes

Answer 10

B cells –> plasma cells (produce antibodies)

T cells = cell-mediated immunity

- CD4 T helper cells
- CD8 T cytotoxic cells

Question 11

lymphoid maturation and migration

Answer 11

all lymphocytes are bone marrow derived

maturation occurs in primary lymph organs

- B cells = bone marrow
- T cells = thymus

migration to secondary lymph tissues
- e.g. lymph nodes, spleen etc

Question 12

lymphopenia

Answer 12

HIV infection (CD4 helper T cells lost)

congenital immune defects

sever bone marrow failure

Question 13

lymphocytosis

Answer 13

reactive = viral infection (EBV)

malignant = CLL

Question 14

lymphadenopathy

Answer 14

reactive = viral infection, local bacterial infection

malignant = lymphoma, metastatic spread