Tolerance and autoimmunity

Tolerance

unresponsiveness of the immune system to self antigens

where does central tolerance occur

lymphoid organs

results of central tolerance

apoptosis

change in receptors

development of regulatory T lymphocytes

where does peripheral tolerance occur

peripheral tissues

results of peripheral tolerance

anergy

apoptosis

suppression

Role of IL-2 in treg function

proliferation and maintenance of regulatory T cells

suppression of effector T cell responses

anergic T cells

not dead, but unresponsive

how can microbes promote autoimmunity

induction of costimulators on APCs

molecular mimicry

Result of passive immunity by transfer of monolonal antibodies

Antibody mediated killing of tumor

Result of passive immunity by transfer of autologous T cells

T cell mediated killing of tumor

Result of adoptive transfer of chimeric antigen receptor T cells

CAR T cell mediated killing of tumor cells

Result of induction of anti tumor immune response in lymph node

primed CTL capable of killing tumor cells

Result of CTL mediated killing of tumor cells

dead tumor cell

result of direct allorecognition

direct CTL killing of graft cells

result of indirect allorecognition

antibody mediated injury to graft cells

inflammation mediated injury to graft

Type A RBC: antigen present

A

Type A RBC: antibodies present

Anti-B

Type B RBC: antigen present

B

Type B RBC: antibodies present

Anti-A

Type O RBC: antigen present

none

Type O RBC: antibodies present

Anti-A and Anti-B

Type AB RBC: antigen present

A and B

Type AB RBC: antibodies present

none