front 1 what is immunological tolerance? | back 1 the layers of protection imposed by the immune system to prevent the reaction of its cells and antibodies against host components |
front 2 what are the four factors that influence immunological tolerance? | back 2 persistence portal of entry; location presence of adjuvants properties of APCs |
front 3 what is antigen sequestration/segregation? | back 3 the process of hiding an antigen from the immune system, typically by isolating it behind physical barriers or within specific compartments, to prevent an immune response |
front 4 what is central tolerance? | back 4 deletion of 'self-reactive' lymphocytes within primary lymphoid organs |
front 5 how does it work in the thymus? | back 5 negative T cell selection, T(REG) production |
front 6 what happens when central tolerance is disrupted? | back 6 APECED/APS-1 genetic deficiency in AIRE TH17 cells |
front 7 TH17 cells | back 7 IL-17A Il-17F Il-22 |
front 8 what is clonal helplessness? | back 8 a mechanism of peripheral tolerance where T cells that encounter their specific antigen in the absence of adequate "help" from CD4+ T cells are unable to develop full, long-lasting function or memory and eventually undergo cell death |
front 9 what is antigen sequestration/immune privilege? | back 9 the partitioning of various self-antigens away from immune mediators if they're not exposed to each other, they're not likely to be reactive this can be problematic, however, particularly in cases of trauma, the eye, or perhaps CTE |
front 10 what is peripheral anergy? | back 10 a state of immune system unresponsiveness in which a lymphocyte, like a T-cell is unable to respond to an antigen even though it is present a T cell needs two signals to activate when T cells encounter a self-antigen without the second co-stimulatory signal |
front 11 how do T(REG)s work? | back 11 cytokine deprivation inhibitory cytokines inhibiting antigen-presenting cells cytotoxicity T(REG)s are known to be: CD4+, CD25+, FoxP3 |
front 12 how does disruption of T(REG)s work? | back 12 immune dysregulation, polyendocrinopathy, enteropathy, x-linked syndrome monogenic, impacts multiple organs, and displays significant immunopathologies caused by a mutation in FoxP3 |
front 13 regulatory CD8+ T cells | back 13 generated in the periphery; act similarly to CD4+ T regs |
front 14 regulatory B cells | back 14 inhibits adaptive immune responses with IL-10 secretion |
front 15 regulatory DCs | back 15 IL-10 secretion |
front 16 myeloid-derived suppressor cells | back 16 contact-independent suppression mechanisms that also suppress in cases of sepsis, trauma, or cancer |
front 17 what is clonal deviation? | back 17 remember that the correct differentiation of T cell subset depends on the polarizing cytokines present at the time of differentiation an immune system process where immature self-reactive T cells that would normally be eliminated by clonal deletion are instead diverted to an alternative differentiation pathway |
front 18 type I response | back 18 intracellular pathogens inducing cell-mediated immunity |
front 19 type II response | back 19 pathogens inducing humoral immunity particularly extracellular parasites |
front 20 what is activation-induced cell death (AICD)? | back 20 repeated stimulation leads to cell death by mitochondrial (intrinsic) or death receptor (extrinsic) pathways mechanism of apoptosis is usually through Fas/FasL interaction |
front 21 what is linkage disequilibrium? | back 21 the non-random association of alleles at different loci |
front 22 how does sex play a role in autoimmunity? | back 22 in general, women are more resistant to infection, but more prone to autoimmunity in general, men are more susceptible to infection and cancer, but have more tolerance for self-antigens |
front 23 what are other potential genetic factors? | back 23 race age sex |
front 24 what are environmental factors? | back 24 diet, geographic location, presence of infection |
front 25 what is molecular mimicry? | back 25 a phenomenon where a foreign antigen from an infectious agent closely resembles a host's own protein or antigen, causing the immune system to mistakenly attack its own body tissue |
front 26 what is bystander activation? | back 26 an immunological process where immune cells, like T cells, are activated by cytokines released during an infection, even if they are not specific to the infecting pathogen |
front 27 what are other potential mechanistic causes of autoimmunity? | back 27 new exposure of self-antigen insufficient clearance of dead cells self-antigen modification |
front 28 what is epitope spreading? | back 28 a process where the immune response expands beyond the initial target epitope to include additional epitopes on the same or different antigens |
front 29 types of local immunity | back 29 hashimoto's thyroiditis type I diabetes myasthenia gravis multiple sclerosis |
front 30 types of systemic autoimmunity | back 30 systemic lupus erythematosus rheumatoid arthritis |
front 31 what are the differences between antibody-mediated immunity (type II), immune complex-mediated autoimmunity (type III), and type IV | back 31 type II uses antibodies to attack cell surfaces, type III forms circulating immune complexes that deposit in tissues, and type IV relies on T cell activation to cause inflammation and damage |
front 32 what are the potential treatments and/or therapies for autoimmunity? | back 32 immunosuppression can be broad-spectrum or target-specific rituximab depletes CD20+ B cells to diminish the pool of cells producing autoreactive antibodies stains lower C-reactive protein, biomarker of inflammation, and reduce pro-inflammatory cytokines abatacept is a CTLA-4/Fc fusion protein that blocks CD28 from CD80/CD86 |
front 33 what is IVIG? | back 33 intravenous immunoglobulin |
front 34 what are the functions of IVIG? | back 34 saturating Fc receptors and inhibiting receptor-mediated phagocytosis saturating FcRn, it inhibits IgG recycling, reduces half life in the blood upregulates expression of inhibitory FcyRIIB to further inhibit phagocytosis |