4 Immunological Tolerance And Autoimmunity Flashcards
(LO) Differentiate acquired tolerance from immunity, immunodeficiency, and immunosuppression
Antigen tolerance is unresponsiveness triggered by previous exposure to a specific antigen.
Immunodeficiency is any condition in which there’s a deficiency or inanity to mount a humoral or cell mediated response. LACKS SPECIFICITY TO ANTIGEN
Immunosuppression is due to physical or chemical insults
(LO) Describe the elements of antigen dose, form, and route of
administration that favor the formation of acquired immune tolerance
Antigen dose favors tolerance if it’s VERY VERY large or small.
Physical: soluble, simple small molecules, not processed
Administration route: ORAL or intravenous
(LO) Describe the mechanisms associated with central tolerance and
peripheral tolerance
Central tolerance occurs in the CENTRAL lymphoid organs bc of immature self-reactive lymphocytes recognizing ubiquitous self-antigen.
Peripheral: induced in peripheral organs as result of MATURE lymphocytes encouraging tissue-specific self antigens
(LO) Using Hashimoto’s thyroiditis and Grave’s Disease as prototypical
autoimmune diseases, explain how autoantibodies can cause
hyperactivity or hypoactivity in a target organ
Hashimoto’s: HYPOactivity thyroid destruction by thyroid specific antibodies. Leukocytes infiltrate
Graves: HYPERactivity. Antibodies bind and activate TSH receptor (agonist)
(LO) Recognize the importance of immunologically privileged sites, and
identify the five human immunologically privileged sites
Brain
Eye
Testes(ovaries)
Uterus
What is specific immunological unresponsiveness triggered by previous exposure to a specific antigen? Antigens that induce this?
Tolerance
Tolerogens
Tolerance is _______ specific and can exist in ________,_______ or both!
Antigen specific
B or T cells
Any condition in which there is a deficiency or inability to mount a humoral and/or cell mediated immune response is a ? What does it lack?
Immunodeficiency
Lacks specificity to antigen
What are antigen factors for immunological tolerance? (3)
Antigen dose Physical form (monomer, aggregates) Route of administration
When you have a VERY large or VERY small dose of an antigen, does this favor immune response or tolerance?
Tolerance
The administration route for _____________ is subcutaneous or intramuscular opposed to the other response, which is oral.
Immune response
If you keep inducing a super small dose (of say an allergy shot) over and over and over again, is this the same as administering a high dose again and again?
YES. Will eventually not recognize it and you will become immune over time
Who favors tolerance more, a newborn or an adult?
Newborn
What’s the physical deletion/elimination of T cells that have receptors specific for self antigens?
By what process?
Results in?
Clonal deletion (apoptotic cell death)
NEGATIVE selection
Results in self tolerance
What’s it called when you have a lack of co-stimulatory signals?
What’s the action of the regulatory (suppressor) lymphocytes?
Clonal allergy
IL-10 inhibits proinflammatory cytokines synthesis..
