Rheumatoid Arthritis and SLE Flashcards
What type of hypersensitivity reaction is SLE?
What is the name of this hypersensitivity reaction?
Type 3
Immune complex
What is SLE?
Immune complexes of DNA and anti-DNA antibodies being deposited in vessels close to the skin surface, causing a skin rash, along with many other organ systems (as it is systemic, hence the name)
Which organs can be affected by SLE?
Eyes Kidneys Skin Lungs Heart Many many more...
Which race is more likely to get lupus?
How many times more likely is their relative risk?
African-Americans
Fivefold over Europeans
Which gender is more likely to get lupus?
How many times more likely is their relative risk?
Females
Tenfold over males
What is the peak age of onset for lupus?
30’s/40’s
Name some common patterns seen in SLE.
Sicca symptoms (dryness - salivary, lacrimal, genital tract)
Joint pain (non-erosive Arthritis, tendinitis)
Skin (photosensitive, alopecia)
Glomerulonephritis
CNS
Eye
What is the difference between apoptosis and necrosis in terms of cellular death?
In necrosis, the cell lyses and releases all its contents = bad as acts as a DAMP’s to trigger innate immune response
Apoptosis = packaged and phagocytosed
What goes wrong in SLE in terms of cell death?
Abnormal apoptosis of cells causes them to act as DAMP’s and trigger innate immune response, which eventually triggers adaptive which causes antibodies to DNA (mostly proteins in the nucleus)
How does rituximab work?
It is a monoclonal antibody that binds to the cell surface protein CD20 (found on B cells)
The binding of these antibodies kills the B cells via both antibody-dependant cellular cytotoxicity AND complement-dependant cytotoxicity (MAC)
In the case of SLE, rituximab therefore prevents B cells from proliferating, differentiating (into plasma cells) and producing more auto-antibodies to DNA auto-antigens
How does Abatacept (CTLA-4) work?
It binds to the CD80/86 part of the 2nd co-stimulators signal, inhibiting it and therefore preventing the second signal without which the T cells can not be activated
What type of hypersensitivity reaction is Rheumatoid Arthritis?
2, 3 and 4
NOT 1!!
What happens to joint space in RA vs OA?
OA = non-inflammatory, but instead mechanical wear and tear = loss of joint space
RA = inflammatory = no loss of joint space, membranes (synovial) inflamed and proliferated, lots of angiogenesis, influx of innate and adaptive immune cells, osteoclasts increase
Which gender is more likely to get RA?
How many times more likely is their relative risk?
Females
Threefold over men
Where does each disease start:
1) OA
2) RA
1) weight bearing joints (knees/hips)
2) peripheral joints (fingers/toes) = works distally to proximally
