Pathoma: Autoimmune Disorders Flashcards
Positive selection is the process in which ________.
T cells are selected based on their ability to bind MHC
Negative selection is the process in which _________.
T cells that bind self antigen are selected out
Double positive cells are found in the ______ of the thymus, while single positive cells are found in _______.
cortex; medulla
What two cells express self antigens in the thymus?
Dendritic cells and medullary epithelial cells
The triad of autoimmune polyglandular syndrome is __________.
adrenal insufficiency, hypoparathyroidism, and candida infections
What is peripheral tolerance?
If a lymphocyte binds antigen in the body without a co-stimulatory signal multiple times (such as CD4 binding to a B cell), it will undergo apoptosis.
Autoimmune lympho-proliferative syndrome (ALPS) is a disorder of _________.
the apoptotic pathway needed for peripheral tolerance
Other than secreting immunosuppressive cytokines, how else do T regs suppress the immune response?
They also express CTLA-4, which binds to B7 on antigen-presenting cells; B7 also binds to CD28 on helper T cells, so interfering with that pathway prevents more activation of CD4 T cells.
What three receptors do Tregs have?
CD4, CD25, and FoxP3
Describe IPEX?
IPEX is an X-linked disorder of the FoxP3 receptor that results in autoimmunity, polyendocrinopathy and enteropathy.
Typically lupus patients have the disease __________.
for the rest of their lives
The ________ complement components are necessary for getting rid of immune complexes.
early
Raynaud’s phenomenon results from _________.
arterio-vaso spasms that limit blood supply to extremities
Both type ____ and ____ immune sensitivities are found in lupus.
II (anemia); III (glomerulonephritis)
What is unique about Libman-Sacks endocarditis?
In LSE, vegetations grow on both sides of the valve, as opposed to the usual one.
Anticardiolipin antibodies can lead to false positive _______ tests.
syphilis
Antihistone antibodies are characteristic of __________.
drug-induced lupus (commonly isoniazid, hydralazine, and procainamide)
The two most common causes of death in SLE are __________.
renal failure and infection
Sjögren’s syndrome is characterized by ________.
type IV autoimmune destruction of the lacrimal and salivary glands
Serum tests in Sjögren’s often show _______.
rheumatoid factor and anti-ribonucleoprotein antibodies
Neonatal lupus (often from Sjögren’s syndrome in pregnancy) can result in _________.
congenital heart block
Biopsy of the salivary gland will show ________ in those with Sjögren’s syndrome.
lymphocyte infiltration
Systemic sclerosis results from ____________.
an autoimmune reaction to mesenchymal cells, leading to fibrosis (collagen deposition) of connective tissue
Those with systemic sclerosis usually have ________ antibodies, while those with diffuse scleroderma have _______ antibodies.
anti-centromere; anti-topoisomerase
