6 Haemopoiesis Flashcards
What are granulocytes?
Basophils
Eosinophil
Neutrophils
Lymphocyte function
B cells-attack invaders outside cells + produce antibodies
T cells- attack infected cells
Monocyte function
Phagocytoses, breakdown and remove microorganisms
Dense against chronic bacterial infections e.g.TB
Causes of monoytosis
-Bacterial infection e.g. TB
-Inflammatory condition e.g rheumatoid arthritis
-Carcinoma-cancer in epithelial tissue
-Leukaemia
Eosinophil function
Immune response against parasitic infection
Causes of eosinophilia
-Allergic diseases e.g. asthma
- parasitic infection e.g. helminths
- skin diseases
- drug hypersensitivity
Basophil function
- release histamine as immune response which causes redness
- help with allergic reactions
- Inflammatory conditions
Neutrophil function
-first responder phagocyte
- part of immune system
Neutrophil on blood smear
3-5 lobed nucleus
2 lobes = immature neutrophil
What is neutrophil maturation controlled by?
G-CSF
Increases neutrophil production
Enhances phagocytosis
Speeds up release o mature cells from BM
What is neutrophilia?
High neutrophil count
Causes of neutrophilia
Acute haemorrhage
Acute inflammation
Infection
Myeloproliferative diseases - blood cancer
Neutropenia causes 2 types
Reduced production
Increased removal/usage
What is neutropenia?
Low neutrophil count
Causes of neutropenia - reduced production
- B12/folate deficiency
- viral infection
- aplastic anaemia - empty marro
- Infiltration - malignancy, no room for BC production
- radiation
Causes of neutropenia - increased removal/usage
-Sepsis- marrow can’t synthesise neutrophils fast enough for demand
- immune destruction-autoantibodies destroy neutrophils
- splenic pooling - separating of neutrophils in spleen, less in circulation
Consequences of neutropenia
-severe bacterial infection
-severe fungal infection
-mucosal ulceration e.g painful mouth ulcers
Erythrocyte function
-deliver O2 to tissues
-carry haemoglobin
-maintain haemoglobin in reduced/ferrous state
-maintain osmotic equilibrium
-generate energy
Splenomegaly causes
- back pressure from portal hypertension
-overworked white/red pulp
-extramedullary haeompoiesis
-infiltration of foreign cells
-waste product accumulation
Hypersplenism meaning
Lack of functioning spleen tissue
Hypersplenism causes
-splenectomy-removal of spleen tissue
- sickle cell disease
-gastrointestinal diseases e.g. coeliac, crohn’s, ulcerative colitis
-autoimmune disorders e.g. rheumatoid arthritis
What can been seen on the blood film of a patient with Hypersplenism?
Howell jolly bodies - DNA remnants
Normally removed by functioning spleen tissue
What does red pulp do?
Removes old RBC
Metabolises haemoglobin
What does white pulp do?
Forms antibodies
Removes bacteria and RBCs covered in antibodies
Encapsulated bacteria which can cause sepsis
Streptococcus pneumonia
Haemophilus influenzar
Meningoccus
What can gastrointestinal diseases cause?
Hyposplenism
What causes hereditary spherocytosis?
Mutations in B spectrum gene
What do mutations in ankyrin and spectrum cause?
Less flexibility of plasma membrane
Spherocytes
How does spherocytes in the blood cause anaemia?
Abnormal RBCs recognised and removed by spleen
Less RBCs > less haemoglobin > anaemia
What does spectrin do?
Links plasma membrane to actin cytoskeleton
What does ankyrin do?
‘anchoring’
Links proteins to spectrin-actin cytoskelton
What does protein 4.2 do?
Regulates association of band 3 with ankyrin
ATP binding protein
What does band 3 do?
-Binds to ankyrin and protein 4.2 to link membrane and cytoskeleton
-facilitates Cl- and HCO3- exchange
What is a trephine biopsy?
1-2cm cord of bone marrow removed usually form hip
Shows structure
What is a bone marrow aspiration?
Takes fluid from bone marrow
Trephine biopsy vs bone marrow aspiration
More information from TP
Less invasive in BMA- smaller needle
What does thrombopoietin do?
Where is it produced from?
Regulates production of platelets
Produced by liver and kidney
Where is erythropoietin released from?
Kidney
