Autoimmune diseases 1 Flashcards
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| 6033938349 | In healthy individuals | Immune system is tolerant of self-antigens | 0 | |
| 6033940127 | Mechanisms that contribute to immunological self- tolerance | -negative selection in the bone- marrow and thymus -expression of tissue-specific protein in thymus - no lymphocyte access to some tissues -suppression of autoimmune responses by regulatory T cells - introduction of anergy in autoreactive B and T cells | 1 | |
| 6033948074 | Capacity of individuals immune system to RESPOND ( or not ) to an IMMUNOGENIC stimulus is the result of | Interaction between inherited MHC complex, environmental stimuli and overall health | 2 | |
| 6033950950 | Inherited MHC haploy heplotypes are | A factor associated with individuals response to infectious agents, may provide initial sensitization for development of autoimmune diseases following re-exposure to crossreactive antigens | 3 | |
| 6033972772 | MHC complex determines binding of a specific antigens motif but effect may | Create a propensity for ability to respond or not | 4 | |
| 6033975097 | Haployte | Indicative of relative risk rather than absolute prediction of response | 5 | |
| 6033976576 | Polygenic nature of MHC | Reflected in pleimorphic nature immune responses generated | 6 | |
| 6033977715 | MHC presentation effects | Both specific humoral and cell- mediated mechanisms By influencing cytokines secretion it involves non- specific effector mechanisims | 7 | |
| 6033981798 | Supermotifs defined by additive method: | 1. A2 supermotif based on A*0201, A*0202, A*0203, and A*0206 alleles 2. A3 supermotif based on A*0301, A*1101, A*3101 and A*6801 allels | 8 | |
| 6033988510 | Autoimmune disease caused by | Loss of tolerance to self antigen | 9 | |
| 6033989480 | Central mechanism of loss of tolerance | Breaking T cell tolerance , is responsible for both cell mediated and B cell response. Antibodies detected by autoimmune conditions rarely 1gM so referring to thymus dependent antigens | 10 | |
| 6033996146 | loss of tolerance - major factor | Incomplete deletion of autoreactive T cells(NB the 10%) Eg. Absence of transcription factor AIRE which induces expression of tissue sepecific proteins in thymus. Result: incomplete negative selection of self- reactive T cells. Individuals homozygous for this mutation (autoimmune polyglandular disease/ APD)or autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (AAPECED) develop autoimmune response in childhood. | 11 | |
| 6034024130 | Loss of tolerance | 3. Insufficient control of T- cell co-stimulation factor ( failure of peripheral tolerance) Production of costimulatory factor by self- reactive tissue cells | 12 | |
| 6034027221 | Loss of tolerance | 4. Failure of regulatory T cells in perifery | 13 | |
| 6034201127 | Failure of regulatory T-cells in perifery | Treg cells uniquely express CD25 (chain of IL-2R) on cell surface and transcriptional suppressor protei , Fox P3. Constitute 5-10% of peripheral CD4 and cells. Subset express RO isoform of CD45 and CTLA-4 molecules. Higher affinity of CLTA-4 molecules foes for B7 (CD 80/86) provides suppressive function by inhibiting stimulators pathway in autoreactive T cell via CD 28-B7 | 14 | |
| 6034234592 | Infections associated with start of autoimmunity | Concept of Mimicry | 15 | |
| 6034235412 | MIMICRY | - active response breakdown of self tolerance: Sequestered or auto-antigens - tolerance: Inability to present potentially protective epitopes | 16 | |
| 6034245888 | All immune diseases involve | Breaking T cell tolerance | 17 | |
| 6034247882 | Mimicry | 1. Same MHC molecule presents a pathogen peptide and a self- peptide that mimics it 2. Naive T cell activated by pathogen peptide presented by particular MHC molecule 3. Effector T(subscript H)1 cell responds to the self peptide mimic and activates macrophage, causing inflammation | 18 |