White Blood Cells Flashcards
(98 cards)
1
Q
What are granulocytes?
A
Leukocytes with granules in cytoplasm
(contain agents for microbicidal function)
2
Q
What are the 4 types of granulocyte?
A
- Neutrophil
- Basophil
- Eosinophil
- Monocytes
3
Q
What are the 3 myeloid growth factors?
A
- G-CSF (granulocyte-CSF)
- M-CSF (macrophage-CSF)
- GM-CSF
4
Q
How do myeloblasts turn into granulocytes?
A
-Cell division to myelocyte
- Differentiation to band form then granulocyte
5
Q
What is the lifespan of a neutrophil?
A
7-10 hours
6
Q
How can neutrophils be identified on a blood film?
A
Segmentend nucleus (3-5 lobes)
7
Q
What is the function of neutrophils?
A
Phagocytoses and kills microorganisms
8
Q
What are the 6 steps of neutrophil chemotaxis?
A
- Adhesion - to vessel lumen
- Margination
- Rolling
- Diapedesis - squeezes through cell gaps in endothelium
- Migration - in tissue to microorganism
- Phagocytosis
9
Q
What must happen to a neutrophils for phagocytosis to occur?
A
Cytokine-priming
10
Q
What is the lifespan of an eosinophil?
A
<Neutrophil
11
Q
What is the function of eosinophils?
A
Fight parasitic infections (eg. helminths)
12
Q
Why are eosinophils important in hypersensitivity?
A
Regulate Type 1 hypersensitivity reactions
- Inactivate histamine and leukotrienes from basophils/mast cells
13
Q
How are eosinophils identified on a blood film?
A
-Red
-Many granules
-Bilobed nucleus
14
Q
What 3 things do basophil granules store?
A
- Histamine
- Heparin
- Proteolytic enzymes
15
Q
What is the function of basophils?
A
Immune and inflammatory responses
16
Q
What are the 2 reactions basophils influence and how?
A
- Type 1 hypersensitivity —> IgE-coated basophils release histamine and leukotrienes
- Inflammatory response —> release heparin and proteases
17
Q
How are basophils identified on a blood film?
A
- Blue
- Packed with granules
18
Q
What are mast cells?
A
Tissue-resident cells involved in hypersensitivity reactions
19
Q
What is the circulation time of a monocyte?
A
Several days
20
Q
Where do monocytes go when they leave circulation?
A
Reside in tissue —> macrophages
21
Q
What are the 3 functions of monocytes?
A
- Phagocytosis of antibody and complement-coated micoorganisms
- Phagocytosis of bacteria/fungi
- Antigen presentation to immune cells
22
Q
What is the 2 function of macrophages?
A
- Phagocytosis
- Store and release iron
23
Q
How are macrophages arranged in the bone marrow?
A
Each encircled by erythrocytes —> delivers iron to them
24
Q
What 3 cells to lymphoid progenitor cells give rise to?
A
- B lymphocytes
- T lymphocytes
- NK cells
25
Where do lymphocytes circulate?
- Recirculate to lymph nodes and tissues
- Then back to bloodstream
26
How are B and T lymphocytes identified on a blood film?
- Small
- Mostly nucleus
27
How in an NK cell identified on a blood film?
- Larger
- Granules
- Clumped nucleus
28
Where do B lymphocytes originate? (2)
- Fetal liver
- Bone marrow
29
Where do B lymphocytes mature?
Bone marrow
30
How do B lymphocytes acquire surface antibodies?
Ig heavy and light chain gene rearrangements
31
How do B lymphocytes develop further in the lymphatic system?
- Exposed to other antigens
- Mature to recognise non-self antigens
32
Where do T lymphocytes originate?
Fetal liver
33
Where do T lymphocytes mature?
Thymus
34
What is the function of T lymphocytes?
Cell-mediated immunity
35
What is the function of B lymphocytes?
Humoral immunity
36
What is the function of NK lymphocytes?
Innate immunity
- kill tumour cells
- kill virus-infected cells
37
What is the cause of transient leukocytosis?
Reactive cause
- Infection/inflammation/infarction
- Bone marrow responding to external stimulus
38
What is the cause of persistent leukocytosis?
Primary blood cell disorders
- Leukaemia/lymphoma/myeloma
- DNA damaged ---> affects haemopoietic precursor cells
39
What is leukocytosis?
Too many white blood cells
40
What are the 5 types of leukocytosis?
1. Neutrophilia
2. Eosinophilia
3. Basophilia
4. Lymphocytosis
5. Monocytosis
41
What is leukopenia?
Too few white blood cells
42
What are the 2 types of leukopenia?
1. Neutropenia
2. Lymphopenia
43
Why may those with leukopenia need isolation?
Very weak immune system
44
What is neutrophilia?
Too many neutrophils
45
What are the 3 causes of neutrophilia?
1. Infection
2. Inflammation
3. Tissue damage
46
What 3 things is neutrophilia also a normal response to?
1. Pregnancy
2. Exercise
3. Corticosteroids
47
What 2 things may accompany neutrophilia?
1. 'Left-shift' ---> presence of non-segmented neutrophils or neutrophil precursors
2. Toxic granulation
48
What is chronic myeloid leukaemia? (CML)
Primary blood cancer
- Myeloproliferative
49
What 3 things can be identified on the blood film of a CML patient?
1. Neutrophilia
2. Basophilia
3. Left-shift
50
What is neutropenia?
Too few neutrophils
51
Which 2 therapies can cause neutropenia?
1. Chemotherapy
2. Radiotherapy
52
What are the 5 causes of neutropenia?
1. Autoimmune disorder
2. Severe bacterial infection
3. Viral infections (some)
4. Drugs
5. Thrombocytopenia
53
Which ethnicities may have a blood film wrongly suggesting neutropenia and why?
African/Afro-Caribbean ---> benign ethnic neutropenia
- More neutrophils parked in vasculature (not actually less neutrophils)
54
What is the biggest risk of neutropenia and how is this combatted?
Serious infection
- urgent intravenous antibiotics
55
How many lobes does the nucleus of a normal neutrophil have?
3-5
56
What is neutrophil hypersegmentation?
Increased number of lobes in neutrophil nuclei
- 'Right-shift'
57
What causes neutrophil hypersegmentation?
Megaloblastic anaemia
- vit B12/folic acid deficiency --- >affect DNA replication ---> nuclei lobes keep dividing
58
What are the 3 neutrophil abnormalities?
1. Neutrophilia
2. Neutropenia
3. Neutrophil hypersegmentation
59
What is 'right shift' and 'left shift' in neutrophils?
1. Right-shift = too many nucleus lobes (overdeveloped)
2. Left-shift = unsegmented nucleus or neutrophil precursors present in blood (underdeveloped)
60
What is eosinophilia?
Too many eosinophils
61
What are the 2 causes of eosinophilia?
1. Allergy (asthma, eczema, drugs)
2. Parasitic infection
62
Which type of leukaemia can present eosinophilia?
CML
63
What is basophilia?
Too many basophils
64
What is the cause of basophilia?
Leukaemia - eg. CML
65
Which leukocytosis is uncommon?
Basophilia
66
What are band forms?
Immature neutrophils
67
How can band forms be identified on a blood film?
- Snake-like nucleus (unsegmented)
- Granules
68
How can myelocytes be identified on a blood film?
- Rounded 'triangle' nucleus
69
What is monocytosis?
Too many monocytes
70
What are the 3 causes of monocytosis?
1. Infection
2. Inflammation
3. Leukaemia (some)
71
What is lymphocytosis?
Too many lymphocytes
72
What is the cause of transient lymphocytosis?
Viral infection
73
What is the cause of persistent lymphocytosis?
Lymphoproliferative disorder - eg. CLL
74
What are the 4 symptoms of chronic lymphocytic leukaemia (CLL)?
1. Weight loss
2. Fevers
3. Night sweats
4. Straw-coloured blood
75
What is lymphopenia?
Too few lymphocytes
76
What are the 4 causes of lymphopenia?
1. HIV
2. Chemotherapy
3. Radiotherapy
4. Corticosteroids
77
Which patients may develop transient lymphopenia?
Severe infection
78
What is leukaemia?
Blood cancer
79
What are the 2 classes of leukaemia?
1. Myeloid
2. Lymphoid
80
Which cells do leukaemic cells replace?
Normal HSCs
81
What proportion of cancers are leukaemias?
5%
82
How do leukaemic cells enter the blood?
Clone ---> replace normal bone marrow cells ---> spill into blood
83
Where do most leukaemias originate?
Bone marrow
84
How does leukaemia occur?
Somatic mutations in a usually oncogenes
85
Why may leukaemic clones replace normal cells? (3)
Growth or survival advantage
1. Don't need usual growth factors
2. Disturbance in proliferation or maturation
3. Failure of apoptosis
86
What is important about the life expectancy of patients with leukaemia?
Shortest of all cancer
87
Why do the terms malignant and benign not apply to leukaemias?
Leukaemias will circulate in the bloodstream and migrate to other tissues (no solid tumour)
88
What 4 types of leukaemia?
1. ALL - acute lymphoblastic leukaemia
2. AML - acute myeloid leukaemia
3. CLL - chronic leukocytic leukaemia
4. CML - chronic myeloid leukaemia
89
What is the difference between the maturity of cells affected by acute vs chronic leukaemias?
- ALL/AML ---> blast cells affected
- CLL/CML ---> mature cells affected
90
Which age group does ALL usually affect and why?
Children
- mutations in utero
91
Which age group does CLL usually affect?
Elderly
92
Why does CML occur?
Fusion protein BCR-ABL1 ---> activates signalling pathways
93
Why does CLL occur?
Steady expansion of leukaemic clone ---> gradually replace normal cells
(B ---> mutation usually in TF gene ---> B won't mature ---> accumulation of blast cells)
94
What are the 4 consequences of leukaemia?
1. Accumulation of abnormal cells
2. Metabolic effects
3. Crowding out of normal haemopoiesis
4. Lose T and B lymphocyte function (CLL)
95
What are the 7 consequences of accumulation of abnormal cells in leukaemia?
(Leukaemia Stops Happiness Because Tumours Stop Life)
1. Leukocytosis
2. Splenomegaly
3. Hepatomegaly
4. Bone pain (ALL/AML)
5. Thymic enlargement (T-ALL/T-CLL)
6. Skin infiltration
7. Lymphadenopathy (ALL/CLL)
96
What are the 4 consequences of metabolic effects of leukaemia?
1. Renal failure ---> hyperuriacaemia
2. Weight loss
3. Fever (low-grade)
4. Sweating
97
What are the 3 consequences of crowding out of normal haemopoiesis in leukaemia?
1. Anaemia - fatigue, lethargy, pallor, breathlessness
2. Neutropenia - fever
3. Thrombocytopenia - bruising, petechiae, bleeding
98
What is the consequence of loss of T and B lymphocyte function in leukaemia?
Weak immune system (CLL)
