Flashcards in Type II Immunopathology Deck (33):
Describe Type I immunopathology.
Symptoms or pathology due to IgE and Th2-mediated events
Describe Type II immunopathology
Pathology due to IgG, IgM, or IgA antibody causing harm to self. Also includes Type V stimulatory antibodies.
Describe Type III immunopathology
Formation of immune complexes which are trapped in basement membranes of blood vessels and activate complement leading to vasculitic inflammation
Describe Type IV immunopathology
Pathologic outcomes of normal or abnormalT cell responses including both helper and cytotoxic cells
What is chronic frustrated immune response?
ADAPTIVE immune response to try to get rid of antigens that never can.
Give examples of things that can cause chronic frustrated immune responses.
Normal gut flora (Crohn's Disease)
Skin flora (Psoriasis)
Chemicals (Chronic Beryllium disease)
Gluten (Celiac Disease)
What are the three mechanisms of tissue damage caused by antibodies?
2. Complement-mediated damage
3. "Stimulatory hypersensitivity"
What is one example of antibody mediated immunopathology that causes neutralization?
Neutralizing anti-interferon (IFN)-gamma autoantibodies found in adults of Southeast Asian decent.
Associated with disseminated nontuberculous mycobacteria
What are three ways in which complement can mediate damage?
1. Create pores in cells
2. Phagocytosis (opsonizing)
3. Phagocytes' lysosomal enzymes and ROS
Give an example of stimulatory hypersensitivity
Describe Graves disease
Long-acting thyroid stimulator that binds to thyroid stimulating hormone receptor and stimulates the thyroid.
What are the symptoms of myasthenia gravis?
Progressive muscle weakness
What is the target for autoantibodies in myasthenia gravis?
AChR the alpha subunit
What happens after the autoantibodies in myasthenia gravis bind to AChR?
Complement and neutrophil mediated destruction
How is Aire implicated in myasthenia gravis?
-Mutated CHRNA1 gene of AChR is mutated
-Aire transcription factor cannot bind too gene
-Protein is not expressed in patients' thymus
-No clonal deletion of Th cell against AChR
-Tfh can activate B cell>>Plasma cell antibodies agains AChR
What are the treatments of myasthenia gravis?
Neostigmine-related drugs (increase effectiveness of ACh)
What do the autoantibodies in Goodpasture syndrome bind to?
Collagen IV found in the basement membrane of the lungs and kidneys
What Goodpasture patients usually get pneumonitis with pulmonary hemorrhage?
Does Goodpasture syndrome usually cause a linear or lumpy-bumpy immunoflorescent stain??
Linear. Antibodies directly against BM
What is Dressler Syndrome?
Autoantibodies that react to the heart after a heart attack or heart surgery.
What are the symptoms of Dressler syndrome?
What bacteria causes rheumatic heart disease?
What is the self antigen in rheumatic heart disease?
Laminin found on the endocardium and valves
What cells mediate the destruction of the cardiac cells?
What is the pathophysiology of autoimmune thrombocytopenic purpura (ATP)?
Autoantibodies bind to platelets and are sequestered by the spleen.
What are some of the common causes of autoimmune hemolytic anemia (AIHA)?
Name some drugs that can cause AIHA.
What autoimmune disorder can cause AIHA?
Paroxysmal cold hemoglobinuria (PCH)
-binding at 15 degrees Celcius
Hyperthyroidism caused by stiumulatory autoimmunity to the TSH receptor on thyroid cells causes what disorder?
Hypothyroidism resulting from autoantibodies to thyroglobulin and thyroid peroxidase resulting in inflammatory and destruction causes what disorder?
Hashimoto disease is found in what patient population?
Females for the most part (5/6)
Name some mechanisms of loss of tolerance.
1. Hybrid (foreign + self) antigen formulation
2. Emergence of forbidden clone
--Ex: Myasthenia gravis
4. Passive antibody
5. Innocent bystander
--Drug bound to RBC
6. Sequestered antigen
7. Failure of regulatory mechanisms
--T cells are not balanced