White Blood Cells

Question 1

myeloid differentiation steps for wbc?

Answer 1

pluripotent HSC –> common myeloid progenitor –> myeloblast –> granulocyte and monocyte/macrophage

Question 2

name the granulocytes?

Answer 2

basophils, eosinophils, neutrophils

Question 3

why are granulocytes called that?

Answer 3

contain granules in cytoplasm that contain agents essential for microbicidal function

Question 4

growth factors for granulocytes/macrophages

Answer 4

G-CSF
M-CSF
GM-CSF

Question 5

general steps for erythrocyte formation?

Answer 5

pro erythroblast –> erythroblast –> erythrocyte

Question 6

features of neutrophil?

Answer 6

segmented/lobulated nucleus

Question 7

main function of neutrophil?

Answer 7

defence against infection, it phagocytoses and kills micro-organisms

Question 8

chemotaxis?

Answer 8

steps:
marginatinated in vessel lumen
adhere to endothelium
migration into tissues

MARDi MP
migration, adhesion, rolling, diapedesis, migration, phagocytosis

Question 9

eosinophil main function?

Answer 9

defence against parasitic infection
important in regulation of Type 1 hypersensitivity reactions
inactivate histamine and leukotrienes released by basophils and mast cells

Question 10

what do basophil granules contain?

Answer 10

histamine, heparin and proteolytic enzymes

Question 11

basophil main function?

Answer 11

involved in a variety of immune and inflammatory responses
e.g.
mediation of hypersensitivity reaction

Question 12

monocyte key roles?

Answer 12

phagocytosis of micro-organisms covered with antibody and complement
phagocytosis of bacteria/fungi
antigen presentation to lymphoid and other immune cells

Question 13

macrophage?

Answer 13

formed when monocytes migrate to tissues where they develop into macrophages

Question 14

macrophage and iron link?

Answer 14

macrophages store and release iron

Question 15

pathway to form lymphocytes?

Answer 15

HSCs –> Common lymphoid progenitor –> NK cells, T lymphocyte/B lymphocyte

Question 16

journey of lymphocytes?

Answer 16

recirculate to lymph nodes and other tissues and then back to blood

Question 17

B lymphocyte development?

Answer 17

development includes Ig heavy and light chain gene rearrangement
This leads to production of surface Its against many different antigens
=humoral immunity
then, in order to mature further, they need to be exposed to antigens in lymphoid tissue e.g. lymph nodes
they will then recognise non-self antigens and produce specific Igs and antibodies

Question 18

T lymphocyte development?

Answer 18

lymphocyte progenitors migrate from foetal liver to thymus which leads to development of T lymphocytes
= cell-mediated immunity

Question 19

NK cells function?

Answer 19

part of innate immunity
can kill tumour cells and virus-infected cells

Question 20

can you differentiate between T and B cells easily?

Answer 20

no

Question 21

what is leukocytosis?

Answer 21

elevated WBC

Question 22

transient leukocytosis?

Answer 22

suggests a secondary cause
occurs when healthy bone marrow responds to external stimulus e.g. infection, inflammation, infarction
(viral infection, parasitic infection)

Question 23

persistent leukocytosis?

Answer 23

due to a primary blood cell disorder
leukocyte count is abnormal due to acquired somatic DNA damage affecting a haematopoetic precursor cell
causes blood cancers such as leukaemia, lymphoma or myeloma

Question 24

leukopenia?

Answer 24

reduced WBC, usually due to neutropenia as neutrophils are most abundant wbc

Question 25

neutrophilia definition causes

Answer 25

= too many neutrophils causes: infection, inflammation, infarction also normal in: pregnancy, following exercise and after administration of corticoids

Question 26

what can neutrophilia be accompanied by?

Answer 26

toxic changes and left shift

Question 27

what is left shift?

Answer 27

presence of early myeloid cells

Question 28

toxic granulation?

Answer 28

heavy coarse granulation of neutrophils

Question 29

chronic myeloid leukaemia

Answer 29

= myeloproliferative disorder neutrophilia, basophilia and left shift

Question 30

why does neutrophilia occur during exercise?

Answer 30

rapid shift of neutrophils from marginated pool to circulated pool

Question 31

what might left shift look like in neutrophilia?

Answer 31

non-segmented neutrophils/neutrophil precursors in blood

Question 32

neutropenia causes?

Answer 32

following chemotherapy and radiotherapy autoimmune disorders severe bacterial infections certain viral infections and drugs might be due to ethnicity e.g. African/Afro-Caribbean ancestry

Question 33

what is a very low neutrophil count?

Answer 33

< 0.5 x 109/l

Question 34

neutrophil hypersegmentation

Answer 34

normal neutrophil has between 3 and 5 lobes hyper segmentation is an increase = right shift usually due to lack of B12/folic acid

Question 35

eosinophilia?

Answer 35

too many eosinophils usually due to allergy/parasitic infection can occur in CML

Question 36

basophilia?

Answer 36

too many basophils usually uncommon and due to leukaemia

Question 37

monocytosis?

Answer 37

too many monocytes usually due to infection or chronic inflammation some types of leukaemia can cause this too

Question 38

lymphocytosis?

Answer 38

too many lymphocytes usually due to a viral infection (transient) can also result from lymphoproliferative disorder (chronic lymphocytic leukaemia) = PERSISTENT

Question 39

what's an important cause of lymphocytosis in children?

Answer 39

whooping cough

Question 40

lymphopenia

Answer 40

too few lymphocytes important causes: HIV infection chemotherapy radiotherapy

Question 41

two classes of leukaemia?

Answer 41

myeloid or lymphoid, depends on what causative tissue is leukaemic cells replace normal haematopoietic stem cells in bone marrow

Question 42

why does leukaemia occur?

Answer 42

a number of somatic mutations the cell now has a growth or survival advantage over normal cells

Question 43

where are the mutations in leukaemia?

Answer 43

oncogenes/sometimes tumour suppressor genes

Question 44

which two terms are used to classify leukaemia?

Answer 44

chronic/acute acute means sudden and severe in onset chronic means disease and deterioration go on for a long time

Question 45

main types of leukaemia

Answer 45

Acute Lymphoblastic Leukaemia Acute Myeloid Leukaemia Chronic Lymphocytic Leukaemia Chronic Myeloid Leukaemia