Tolerance and Regulation of the Immune Response

Tolerance

specific immunilogical non-reactivity specific antigen resulting from a prevous exposure to the same antigen

Tolerogen

an antgen used to introduce tolerance

Anergy

absence of the normnal immune response to a particular antigen or allergen

True or False: Immunological tolerance is an active response to a particular epitope and is just as specific as an immune response.

TRUE

Tolerance at the B/T cell level is longr lasting.

T

Acquired immune responses are _____ driven

antigen

T cells respond optimally to presented antigens for _______ days

3-5

True or False: Once antigen concentration drops below a threshold, response stops.

TRUE

True or False: Co-stimulation is necesary for activation of a T cell

TRUE

When a T cell exhibits CTLA-4 on its surface it is tolerogenic and inhibits co-stimulation to cause ______.

anergy

When will a T cell enter a state of anergy?

1. low doses of antigen are present

2. lack of co-stimulation

3. expression of CTLA-4 on the surface of a T cell

What do regulatory T cells possess that allows for IL-2 t cause proliferation?

CD25

How does CD25 help T rehulatory cells induce toelrance?

it “starves” the CD8+ cell from having IL-2 and proliferating

What are the three pathways of peripheral B cell tolerance?

1. clonal exhaistion

2. functional deletion

3. receptor blockade

True or False: Excessive antibodies can never be a problem.

FALSE

What happens if CD28 is blcoked?

IL04 not prodiced → no antibodies

If the antigen cross-links the BCR and Fc/CD32 receptor, signal transduction is _____.

inhibited

How does BCR and Fc?CD32 regulate antibodies?

prevents B cell activation and triggers apoptosis

WHat do regualtory T cells do?

maintain toelrance to self-antogens and prevent autoimmune disease

What do regulatory T cells express?

CD4, CD25, and FOXP3

Regulatoryy T cells are CD____+

4

Regulatory T cells produce ____ cytokines like:

suppressive; TGFb, IL10, IL35

True or False: All FOXP3 cells suppress inflammtion.

FALSE - T helper 17 enhance inflammation

IL-17 upregultes what cell?

neutrophils