Immune Tolerance Continued

Question 1

What is the result of CTLA4 gene polymorphisms?

Answer 1

Failure of CD4 anergy
Infiltrate organs
Lymphoproliferation

It terminates activation of T cells
On reg T cells, supresses native T activation

Question 2

What disease is CTLA 4 polymorph associated with

Answer 2

Type 1 diabetes

Question 3

What effects does Fas/fast poly morph have?

Answer 3

ALPS disease( autoimmune lymphoproliferative syndrome(

Get lymph proliferation hepatomegly spleenomegly

Defect in apoptosis detective deletion of anergic B cells

Question 4

What leads to IPEX dis ease

Answer 4

Defect in Fox P3

Question 5

What is characteristic of IPEX

Answer 5

’ Deficent regulator T cells
Severe autoimmune diseases
Mutated fox p3 means issue with development of CD 4 T reg
dermatitis thyroiditis early death

Question 6

What are the four ways to prevent autoimmunity and what disease corrolates to a breakdown of each

Answer 6

Immuno tolerance-physical barriers that separate-sympathetic opthalmeia
Deletion-delete auto reactive T cells via fas binding-ALPS
Inhibition- auto reactive T cells expressing ctla4 bind b7 so no activation of T cells- diabetes
Suppression-T reg produce inhibitory cytokines il10 and TGFb so auto reactive T cells arent activated-ipex

Question 7

What are the three factors contributing to autoimmunity

Answer 7

Genes(MHC most associated)
Environment
Immune regulation

Question 8

Discribe the 4 diseases that are associated with HLA genes

Answer 8

Ankylosing spondylitis-CLASS 1- highest riskB27
RA-CLASS 2
Type 1 DIABETES- CLASS 2
Pemphigus vulgaris-CLASS 2

Do not cause increase risk

Question 9

What are for triggers of autoimmunity

Answer 9

Molecular mimicry
Polyclonal activation
Epitope spreading
Cryptic antigen

Question 10

Describe molecular mimicry and the disease associated

Answer 10

-cross reactivity
Step triggers rheumatic fever and get cross reactivity with cardiac myosin

Question 11

Describe polyclonal activation as a trigger for autoimmunity

Answer 11

Strong cytokine environment leads to bystander activation,regardless of antigen)

Question 12

Describe epitope spreading

Answer 12

Triggers for autoimmunity
Immune response to new secondary epitope distinct from primary

Question 13

Describe cryptic antigen in autoimmunity

Answer 13

Tissue damage leads to previously hidden antigen that activate auto reactive T cells