Haematological Cancers Physiology Flashcards
lifespan of a neutrophil
7-8 hours
what is a blast?
nucleated precursor cells (erythroblasts and myeloblasts)
platelet precursor
megakaryocyte
what regulates platelet production?
thrombopoietin, a glycoprotein produced by the liver and kidney
what is a reticulocyte?
immediate red cell precursor (polychromasia)
what is a myelocyte?
nucleated precursor between neutrophils and blasts
development events in haemopoiesis
self-renewal proliferation differentiation maturation apoptosis
define pluripotency
ability to differentiate into a specific type of lineage of blood cell
which layer of the embryo do HSC originate?
mesoderm
sites of haematopoiesis in the embryo
yolk sac
liver starts at week 6
bone marrow at week 16
when is the cellularity of bone marrow highest?
when born and decreases with age
IgM
recent infection
IgG
past infection
what are immunoglobulins?
antibodies produced by B cells from plasma cells
what are immunoglobulins made up of?
2 heavy (μ, α, δ, γ, ε) 2 light chains (κ or λ)
role of immunoglobulins
each recognises a specific antigen due to the presence of their variable region
immunoglobulins that are monomers
IgD
IgE
IgG
immunoglobulins that are dimer
IgA
immunoglobulins that are pentamer
IgM
where do B cells go once out of the bone marrow?
germinal centre of the lymph node where it enters and improves the fit by somatic mutations or it is deleted (self)
where does the B cell go after the germinal centre?
may go to the marrow as a plasma cell or circulate as memory B cell
what do plasma cells produce?
antibodies
what do plasma cells look like on blood film?
clock face nucleus
plentiful blue cytoplasm
pale perinuclear area (golgi apparatus)
what causes a polyclonal increase in immunoglobulins?
infection
AI
malignancy
liver disease
what does monoclonal increase in immunoglobulins indicate?
underlying problems
what is monoclonal immunoglobulins called?
paraprotein (used as a marker for underlying disease)
causes of paraproteinaemia
myeloma MGUS amyloidosis lymphoma plasmacytoma CLL Waldenstrom's
methods used to detect immunoglobulins
- serum electrophoresis
2. serum immunofixation
what is serum electrophoresis
separates proteins based on size and charge which appear as bands
what is serum immunofixation?
classified abnormal protein bands seen on electrophoresis
what is the Bence Jones Protein (BJP)?
immunoglobulin light chains detected by urine electrophoresis
how is the BJP detected?
urine electrophoresis
what causes BJP?
excess light chain production cause it to leak into the urine and precipitate into the BJP
