White blood cells

Question 1

Neutrophils - general info

Answer 1

AKA - polymorphs, PMN’s, segmented neutrophils
large = 10-15micometers diameter
dense nucleus w 2-5 lobes
granules in cytoplasm
make up about half of the white cell count

Question 2

Neutrophil timeline

Answer 2

7-10 days maturation in the marrow

circulate for 6-10 hours in the blood then migrate into tissues where perform phagocytic function

Question 3

Why don’t we transfuse granulocytes to patients undergoing chemo, when we can give them RBC’s and platelets

Answer 3

they have too short a circulation time…

Question 4

What is a a left shift?

Answer 4

In a patient where the marrow is under stress e.g. responding to infection or inflammation, may see some more immature forms that you would normally see in the marrow –> are released in the peripheral blood

Question 5

Leukemias.. in a blood film?

Answer 5

arise from the very early stages of myeloid development, proliferation of immature cells that replace the marrow and spill over into the blood

Question 6

Regulation of granulopoiesis

Answer 6

Haematopoietic growth factors, IL-3 stem cell factor, GM- CSF, and G-CSF (granulocyte colony stimulating factor) –> used to treat neutropenia

Question 7

Neutrophil function

Answer 7

1. chemotaxis
2. phagocytosis
3. killing of bacteria - using enzymes stored in granules, can be oxidative or non-oxidative

Question 8

clinical relevance

Answer 8

Neutrophil leukocytosis
- feature of infection and inflammation
- may be associated with a left shift i.e more immature forms of blood
Patients with low neutrophil count = neutropenia
–> could be idiosyncratic e.g. reaction to a drug you’ve prescribed, OR expected consequence or complication from chemotherapy
At risk of infection = febrile neutropenia –> particularly of the skin / rest tract
Neutrophil function defects rare

Question 9

What are the phagocytes?

Answer 9

Granulocytes: neutrophils, eosinophils, basophils

Monocytes

Question 10

What are the lymphocytes?

Answer 10

B an T lymphocytes and NK cells

Question 11

Monocyte kinetics

Answer 11

Circulates for 1-3 days 
Enters tissue and transforms into macrophage 
Related cells throughout the body 
- Kupffer (liver)
- Alveolar macrophages 
- Langerhans skin cells 
- mIcroglial cells (brain)

Question 12

Monocytes - clinical relevance

Answer 12

Infrequent
Monocytosis
- relative - chronic infections e.g. TB, osteomyelitis
- Malignant - acute myeloid leukaemia (monoblastic sub type) chronic myelomonocytic leukaemia (CMML)

Question 13

Monocytes basic info

Answer 13

large cell = 15-20 micrometers
central oval or indented nuclei
blue - grey cytoplasm with granules

Question 14

monocytes / macrophage function

Answer 14

chronic infections, intracellular parasites e.g. TB
- chemotaxis
- Opsonisation
- Phagocytosis and ingestion
- killing off ingested bacteria by fusion with monocytic lysosomal granules
phagocytic cells
synthetic functions
–> complement interferons, cytokines e.g. TNF, IL-1, growth factors, prostaglandins
Antigen presentation

Question 15

Eosinophil basic info

Answer 15

bilobed nucleus
Red staining granules
Developmental stages similar to neutrophils

Question 16

Eosinophilia

Answer 16

allergic or hypersensitivity rections e.g. hayfever, asthma, drug reactions, parasitic infections –> gut parasites (refugees, travellers in 3rd world countries)

Question 17

Basophil basic info

Answer 17

Infrequent cells in blood
Deep blue granules over nucleus
IgE binding sites
Related to mast cells

Question 18

Basophil function

Answer 18

Granules - histamine, SRS-A, ECF-A
Type I hypersensitivity - degranulate
close relationship with mast cells

Question 19

Lymphocytes - basic info

Answer 19

about 10 microms diameter 
- small mature cells 
High N:C ratio 
Condensed chromatin nuclei 
thin rim of granular cytoplasm

Question 20

B vs T lymphocytes

Answer 20

65-80% T cells
5-15% B cells
Morphologicallyidentical, identify by cell surface markers

Question 21

Lymphocyte cells functions

Answer 21

Lymphoid cells - specific immune responses
B cells - plasma cells = antibody production
T cells - cell mediated immunity
CD4 positive T helper cells
CD8 positive T cytotoxic cells

Question 22

Primary lymphoid organs

Answer 22

Lymphocyte bone marrow derived but maturation occurs in primary lymphoid organs
B cells = bone marrow
T cells = thymus (learn to recognise self from non-self)

Question 23

secondary lymphoid organs

Answer 23

migrate from primary lymphoid organs to secondary lymphoid tissues

• lymph nodes
• spleen
• lymphoid tissue thought the body e.g. gut, respiratory tract etc
• bone marrow

Question 24

Lymph node enlargement: clinical relevance

Answer 24

Reactive: e.g. viral infection, local bacterial infection

Malignant e.g. of lymphoid tissues (lymphoma) or metastatic spread

Question 25

Lymphocytosis

Answer 25

= inc in lymphocytes
Reactive = viral infections e.g. infectious mono –> lymphocytes have changed shape, look more like monocytes
Malignant e.g. chronic lymphocytic lukemia, look normal in morphology, just massively increased in number