Autoimmunity Flashcards
primary lymphoid organs
- bone marrow
- thymus
secreted antibodies bind to extracellular microbes which promotes their ingestion by _______ cells
- phagocytic
what enhances the microbe-killing abilities of phagocytic cells (macrophages)
- helper T cells
what type of cell recruits leukocytes to destroy microbes and strengthen epithelial barrier function to expel microbes
- helper T cells
what cell type destroys cells infected by microbes that are inaccessible to antibodies
- CTLs
what cell types suppress activated T cells to down regulate the adaptive response
- regulatory T cells
most cytokines are produced by what type of cell
- T helper lymphocytes
what are the acute-phase response cytokines
- TNF
- IL-1
- IFN-gamma
- IL-6
IL-1 affect on T cells
- Th 17 differentiation
action of IFN-gamma
secreted by
- activation of macrophages
- NK cells
- T lymphocytes (Cd4 and Cd8)
action of IL-6
- synthesis of acute phase proteins in liver
action of IL-2
- T cell proliferation
- regulatory T cells survival
action of IL-4
secreted by
- B cell switching to IgE
- Cd4 T cells
- mast cells
action of IL-5
secreted by
- activation of eosinophils
-Cd4 T cells
- mast cells
- innate cells
action of IL-17
secreted by
- stimulate acute inflammation
- Cd4 T cels
action of IL-22
secreted by
- maintenance of epithelial barrier function
- Cd4 T cells
- NK cells
action of TGF-beta
secreted by
- inhibition T cell activation
- help T regs differentiate
- Cd4 T cells
what cytokines are present in both innate and adaptive immunity
- IFN-gamma
- TGF-beta
which class of helper T cells produces IFN-gamma
- what about IL-4, IL-5, IL-13
- what about IL-17, IL-22
- Th1
- Th2
- Th17
CXCL2 (MIP-2) recruits what cells
- naive T cells
CCL2 (MCP-1) recruits what cells
- macrophages
which cytokine supports the growth of multi-lineage bone marrow stem cells
- IL-3
what promotes the production of colonies of the different leukocytes in the bone marrow and enhances their activity
- colony-stimulating factor (CSF)
what cytokine plays a role in the survival and proliferation of immature B lymphocytes and T lymphocyte precursors
- IL-7
what antibodies are involved in type III HS
- IgG and IgM
Type I diabetes is what type of hypersensitivity reaction
- Type IV (T-cell mediated)
what type of hypersensitivity reaction is the delayed type
- Type IV
where does positive selection of T cells occur?
what occurs?
- cortex of thymus
- double positive CD4/CD8 T cells must react to self MCH protein
where does negative selection of T cells occur?
what occurs?
- medulla of thymus
- must NOT react to self peptides on MHC molecules
- deletes possible auto-reactive T cells
what are antigens that induce tolerance
- tolerogens
two mechanisms for central T lymphocyte tolerance
- deletion
- development of regulatory T cells
cell surface markers for regulatory T lymphocytes
- Cd3/4/25
what cell requires transcription factor FoxP3 for function
- regulatory t cells
expression of regulatory T cells induced by
- TGF-beta
mechanisms for peripheral T lymphocyte tolerance
- anergy - functional unresponsiveness
- suppression - block in activation
- deletion - apoptosis
central tolerance is induced by _____ (mature/immature) lymphocytes encountering antigens in _________
- immature
- generative, central lymphoid organs
peripheral tolerance induced by ______ (mature/immature) lymphocytes encountering antigens in _______
- mature
- peripheral tissues
3 requirements for autoimmunity to occur
- individual must express MHC molecules
- must produce T and B cells that have receptors that recognize self antigens
- must be environmental factors that lead to breakdown of tolerance mechanisms
