浙江大学研究生免疫学英文课件抗原递呈细胞APC.ppt

APC Properties and Functions of Antigen-Presenting Cells DC: morphology DC are identified morphologically by their membranous or spine like projections DC:location DC are present in lymphoid organs, in the epithelia of the skin and gastrointestinal and respiratory tracts, and in the interstitium of most parenchymal organs DC: Classification Origin Location Development migration 1)DC: Classification according to origin myeloid DCs (mDC or classical or conventional DCs , cDCs) plasmacytoid DCs (pDCs) pDC Plasmacytoid DCs circulate through the blood and lymphoid tissues and only acquire the typical DC morphology after activation, which is accompanied by the release of type I interferons (IFNs), this is why they are sometimes referred to as“IFN-producing cells”. pDC The pDCs develop fully in the bone marrow and then enter the bloodstream. In the steady state, the pDCs are present in the thymus and all secondary lymphoid organs, but they are difficult to detect in most peripheral tissues. pDC Function: pDC can activate naive T cells, as well as memory T cells, if they undergo maturation. The expression of MHC and T cell costimulatory molecules on activated pDCs is not as high as on their cDC counterparts, and this is probably why pDCs tend to be less efficient at T cell priming than cDCs. 3,DC:maturation DC maturation Immature DCs are well equipped with a series of receptors for pathogen-associated molecular patterns and for secondary inflammatory compounds, such as Toll-like receptors (TLRs), nucleotide-binding oligomerization domain (NOD) proteins, RIG-I-like receptors, C-type lectin receptors, cytokine receptors and chemokine receptors. DC maturation Immature DCs are well equipped with a series of receptors for pathogen-associated molecular patterns and for secondary inflammatory compounds, such as Toll-like receptors (TLRs), nucleotide-binding oligomerization domain (NOD) proteins, RIG-I-like receptors, C-type lectin receptors, cytokine receptors and chemokin