Immunologucal Tolerance And Autoimmunity BLOCK 6 Flashcards
Tolerance to non self
- will not develop MHC Ab if exposed enough
- or if body is overwhelmingly over attacked. Can give wrong blood type to prevent death
Specific immunological unresponsiveness triggered by previous exposure to a specific antigen
Tolerance
Antigens that induce tolerance
Tolerogens
Tolerance is _________ and results from the recognition of antigens by specific lymphocytes
Antigen specific
Normal people show _______
Self tolerance
Foreign bodies may be administered in ways that preferentially inhibit immune response by inducing tolerance in specific lymphocytes
Antigen induction
Similarities of induction of tolerance to induction of immunity
- tolerance is an antigen-induced active process
- tolerance is antigen specific
- tolerance can exist in B cells, T cells or both
Tolerance can exist in what
B cells, T cells or both
Any conduction in which there is a deficiency or inability to mount a humoral and/or cell-mediated immune response
Immunodeficiency
What does immunodeficiency lack
Specificity to antigen
The suppression of immune responses to antigens due to physical or checmical insults
Immunosuppression
Immunosuppression lacks
Specificity to antigen
When there is no tolerance
Immunodeficiency
Antigen factors
- antigen dose
- physical monomer (better than aggregates)
- route of administration
Host factors in immunological tolerance
- hereditary
- age
- gender
- health
Dose of antigen that favors immune response
Optimal dose
Dose ofantigen that favors tolerance
Very large or very small dose
Physical form of antigen to favor immune response
Large, aggregated complex
Physical form of antigen that favors tolerance
Not processed
Administration route that favors immune response
Subcutaneous or intramuscular
Age of responding animal that favors immune response
Adult
Age of animal that favors tolerance
Newborn
Occurs in the central lymphoid organs as a consequence of immature self-reactive lymphocytes recognizing ubiquitous SELF TOLERANCE
Central tolerance
- thymus for T cells
- Bone marrow for B cells
Induced in peripheral organs as a result of matur eeself reactive lymphocytes encountering tissue specific self antigens under particular conditions.
Peripheral tolerance
Outside bone marrow and thymus
Physical deletion/elimination of T cells tha have receptors specific for self antigens
Colonial deletion (apoptotic cell death)
How does clonal deletion work
Via negative selection
What does clonal deletion results in what
Self tolerance
Lack of co-stimulators signals
Clonal anergy
Clonal anergy is the action of
Regulatory (suppressor) lymphocytes
A failure to control the function of self-reactive cells which escaped to the periphery, results in
Autoimmune disease. Tolerance fails
Type I DM is what
Type 4 hypersensitivity, AI
Hemolytic anemia
AI
Type II hypersensitivity
Antibodies against the receptors can ________ or _______ the receptor in autoimmune disease
Activate
Destroy
Is autoimmune disease always destructive?
No
What is an example of an AI that activation occurs
Grave’s disease
Thyroid stimulating hormone receptor agonist
What is an example of destructive AI
Myasthenia Gravis
Ach receptor antagonist
What’s the difference between Graves Vs Hashimotos
Hashimotos turns thyroid to hash, HYPOthyroidism
What does Graves’ disease result in
hyperthyroidism
What does Myasthenia Gravis result in
Progressive weakness
Destruction of thyroid by thyroid specific antibodies. The “brake”, results in hypothyroidism
Hashimotos
Antithyroid stimulating hormone receptor antibody. The “gas” pedal. Hyperthyroidism
Graves’ disease
Immunologically privileged sites
- brain
- eye
- testes/ovaries
- uterus
