Autoimmunity Flashcards
All of the following probably contribute to the development of autoimmunity EXCEPT
a. cross-reactivity of pathogen and self antigens.
b. expression of self antigen in the thymus or bone marrow.
c. low avidity presentation of some self peptides in the thymus.
d. random generation of TCR and BCR specificities.
e. tissue injury which releases normally hidden self antigens.
b. expression of self antigen in the thymus or bone marrow.
The elimination of self-reactive T cells during thymus education is called
a. apoptosis.
b. clonal selection.
c. clonal anergy.
d. negative selection.
e. positive selection.
d. negative selection.
An autoimmune disease mediated by Type III hypersensitivity is
a. autoimmune hemolytic anemia caused by anti-A blood group antigen.
b. Grave’s Disease caused by anti-TSH receptor antibodies.
c. IDDM caused by CTL to islet antigens.
d. Lyme arthritis caused by immune complexes resulting from a persistent infection with Borrelia burgdorferi.
e. Myasthenia gravis, caused by antibodies to the acetylcholine receptor
d. Lyme arthritis caused by immune complexes resulting from a persistent infection with Borrelia burgdorferi.
Tolerance is induced by all of the following EXCEPT
a. administration of antigen with adjuvant.
b. clonal anergy of self-reactive mature T cells which bind antigen without co-stimulation.
c. clonal deletion of self-reactive immature B cells whose BCR is extensively cross-linked by antigen.
d. failure of particular MHC alleles to present certain peptides.
e. regulatory T cells that suppress immune responses.
a. administration of antigen with adjuvant.
Autoimmune diseases which are Type II hypersensitivities include all of the following EXCEPT
a. Goodpasture’s syndrome cause by autoantibodies to Type IV collagen.
b. insulin-resistant diabetes caused by autoantibodies to insulin receptor.
c. multiple sclerosis caused by Th1 cells specific for proteins in the brain and spinal cord.
d. pemphigus vulgaris caused by autoantibodies to epidermal cadherin.
e. rheumatic fever caused by antibodies to streptococcal antigens that cross-react with heart tissue.
c. multiple sclerosis caused by Th1 cells specific for proteins in the brain and spinal cord.
Induction of autoimmunity usually involves
a. activation of antigen-specific T cells.
b. anergy of antigen-specific B cells.
c. development of autoimune disease in everyone with certain HLA alleles.
d. occurrence of infection in the absence of inflammation.
e. recruitment of antigen-specific dendritic cells to T cell areas of the lymph nodes.
a. activation of antigen-specific T cells.
The chances of developing a given autoimmune disease are linked to all of the following EXCEPT
a. contracting an infectious disease.
b. gender.
c. having an identical twin with the disease.
d. inheriting certain HLA alleles.
e. total absence of thymus edu.cation
e. total absence of thymus edu.cation
Autoantibodies to a cell surface receptor
a. bind the cell to mimic the action of the natural ligand for that receptor
b. block cell activation via that receptor.
c. cause the destruction of the cell by ADCC.
d. cause the destruction of the cell via complement-mediated lysis.
e. All of the above are possible consequences.
e. All of the above are possible consequences.
Organ-specific autoimune diseases include all of the following EXCEPT
a. autoimmune hemolytic anemia.
b. Hashimoto’s thyroiditis.
c. insulin-dependent diabetes mellitus (IDDM).
d. myasthenia gravis.
e. rheumatoid arthritis.
e. rheumatoid arthritis.
Increased risk of developing Type 1 diabetes (IDDM) associated with HLA DR3 and DR4
a. can be lowered by the presence of HLA DR2.
b. has been discovered to be due to a genetic mutation in those alleles induced by closely linked DQb.
c. means that everyone with those HLA alleles will develop diabetes during his or her lifetime.
d. occurs because DR3 and DR4 cannot present self antigen in the thymus.
e. protects individuals with IDDM from malaria.
a. can be lowered by the presence of HLA DR2.
Of the following, it is usually the easiest to identify specific
a. antigens for which autoimmune T cells are specific.
b. antigens to which autoantibodies are being produced.
c. environmental factors which promoted development of autoimmunity.
d. pathogen antigens which initiated the autoimmune response.
e. All of the above are equally easy to determine.
b. antigens to which autoantibodies are being produced.
Determinant spreading occurs when
a. antigenic epitopes move from one cell to another.
b. B cells specific for one epitope provide co-stimulation to Th2 cells specific for different epitopes.
c. CTL killing leads to release of new antigens to which B cells can produce antibodies.
d. Th2 cells specific for one epitope on an antigen complex activate B cells specific for several different epitopes on that same complex.
e. Answers b, c and d are examples of how determinant spreading could occur.
e. Answers b, c and d are examples of how determinant spreading could occur.
Feeding of myelin basic protein (MBP) to mice prevents them from later developing experimental autoimmune encephalomyelitis when they are injected with MBP and adjuvant. The mechanism by which antigen feeding prevents EAE is though to be
a. activation of regulatory T cells producing IFNg.
b. activation of regulatory T cells producing TGFb.
c. clonal anergy of all MBP-specific T cells.
d. clonal deletion of all MBP-specific T cells.
e. induction of an IgE response instead of an IgG response to MBP.
b. activation of regulatory T cells producing TGFb.
Immunological ignorance to an antigen occurs when
a. all lymphocytes specific for that antigen have undergone clonal deletion or clonal anergy.
b. the antigen is absent from the body (non-self).
c. the antigen is presented on self MHC with such high avidity that specific T cells are activated to undergo apoptosis.
d. the antigen is presented on self MHC at such low avidity that specific T cells are not activated.
e. the antigen is sequestered in the cell cytoplasm.
d. the antigen is presented on self MHC at such low avidity that specific T cells are not activated.
Self-specific B cells are not generally responsible for the induction of autoimmunity because they
a. are not present in the body.
b. can be activated by self antigens but not produce any self-specific antibodies.
c. cannot be activated by binding cell surface antigen.
d. require activation by self-specific T cells, whose activates are more tightly regulated than those of B cells.
e. undergo somatic recombination, which eliminates self-specific B cells.
d. require activation by self-specific T cells, whose activates are more tightly regulated than those of B cells.
