CBE cortisol/calcium practicals Flashcards
What are binding assays
analyte is assessed by its ability to bind:
types of binding assays
- ligand
- receptor
steps of ELISA immunoassay
- coating: antigen-protein coat the wall
- detergent wash excess conjugate
- proteins like BSA will be used to fill the gaps
- MOST IMPORTANT - standard/sample cortisol (antigen) and cortisol antibodies will be put in the well
- The more cortisol antigen put in, the less cortisol antibodies that are open to bind to the antigen on the wall
- An enyzme binding the antibody will be added in
- the subtrate of the enzyme is added, the more enzyme, the more intense colour.
The more cortisol put in, the less intense colour
types of immunoassays
homogeneous: no separation step
heterogeneous:
- depends on which bind assay it is
separate free/bound binder.
separate free/bound ligand.
What kind of immunoassay is ELISA?
enzyme-linked
evaluation of ELISA results
- accuracy
- parallelism (dilution experiments)
- precision (replicate experiments)
forms of calcium in blood
- calcium complexed: with phosphate, citrate
- free/ionised: regulated by PTH
- albumin-bound: changes with albumin concentration
acidaemia and alkaemia: changes in H+ and Ca2+
in alkaemia, Ca2+ tends to bind more with albumin
in acidaemia H+ displace Ca2+
total calcium levels and albumin levels
if albumin level below reference range, the calcium level will add.
multiple myeloma and hypercalcaemia
malignant proliferation of plasma cells in the bone marrow:
the cells will activate osteoclast precursors through RANKL-RANK interaction
decalcification of osteoid (bone resorption) - hypercalcaemia
bone weakness
what is multiple myeloma
a cancer in the bone marrow that affects plasma cells
The plasma cells will produce many monoclonal immunoglobulins.
