What is rituximab?
A chimeric monoclonal antibody to human CD20 (found on pre/mature B cells)
How does C1q meaure Immune complexes?
Radiolabelled C1q is used to bind to circulaing immune complexes
-remember C1q combines with r2s2 to cleave C4 and C2
What does a reduced CH50 indicate?
Reduced levels of classical and or/MAC components
an AH50 measures the alternate pathway
In a person with an active immune response, why would C3 and C4 levels be reduced?
The production of immune complexes may reduce serum C3 and C4 levels, which would be expected if there is an immune response
What are the components of a chimeric ab?
A chimeric antibody is fusion of a moutse antigen-binding Fab region (variable domains of the heavy and light chains, VH and BL) from one species like a mouse, with a the Fc constant domain
After using ritizumab what CD should you look for to monitor therapy?
CD19 becuase rituximab is killing the CD20
What is used to isolate the variable mouse region for a monoclonal antibody?
What type of Hypersensitivity is Serum sickness?
Type III immune complex
How do you treat serum sickness to ritxuimab?
Take them off the medication, and maybe give steroids
In serum sickness to Rituximab what is patinet producing antibodis against?
The mouse Fab grament, patient is having an IgG response
What happens to the deposited immune complexes in serum sickness?
They are removed by phagocytes
-this is because they are large complexes, smaller complexes are carried to the liver by CR1 erythrocytes and removed
What is serum sickness?
It is a type III hypersensitivity reaction, in which the person has developed an immune response against some type of therapy (Drugs, Mab, etc.)
What is being used to overcome and diminish the possibility of serum sickness?
Using chimeric antibody.
-The less foreign the antibodies are the less chance of producing antibodies should be.
What is an arthus reaction?
Localized Type III hypersensitivty reaction, like in a local immune complex deposition due to immunization
What are the examples of Type I hypersen?
Allergy, asthma, eczema, anaphylactic shock
What are the type II hypersen examples?
True autoimmune disease like Myastania Gravis and Graves disease
What are the type III hypersen examples?
Lupus, serum sickness, arthus reaction, also RA
What are type IV examples?
Chron's disase, sarcoidosis, poison ivy, MS, Hasimotos
What is the cause of capillaritis?
Capillaritis can be due to a number of causes, but a reaction to a drug is the most common, although the actual mechanism is disputed. It is due to blood leaking from the capillaries.
Suggest a mechanism for the a raised ESR?
Activated phagocytes will induce an acute phase response, with resultant production of liver proteins which bind to RBC
Why were the BUN and serum creatinine raised?
Immune complexes were depositied in the kidneys resulting in redued renal function