Immunopathology (5 and 6) Flashcards
Innate immune system
Barrier and chemical mechanisms, PRR, cellular (phagocytes, natural killer cells)
Adaptive immune system
Humoral or cellular
Pattern recognition receptors
Antigen recognition receptor in the innate system
What do pattern recognition receptors usually detect?
Pathogen-associated Molecular Patterns (PAMPs) but also Danger Associated Molecular Patterns (DAMP’s)
2 Groups of PRR
- Cell surface (transmembrane) and intracellular receptors -TLRs, NLRs, RLR’s and CLR’s
- Fluid-phase soluble molecules
Fluid-phase recognition molecules
C-type lectin family
- Collections - Mannan-binding Lectin/Surfactant protein A & D
- Recognition of microbal complex carbohydrates
Fluid-phase recognition molecules role
Neutralisation of pathogen and recruitment of adaptive response
What do fluid-phase recognition molecules bind via
Carbohydrate-Recognition Domains (CRDs)
IL1
First cytokine in response to infection makes you feel ill
Other important cytokines
TNF, IL6, IL23
Plasmacytoid dendritic cells
Produce IFN (circulate in blood)
Myeloid dendritic cells
Produce IL12 and IL10 (circulate in blood)
Natural killer cells
Kill foreign and host cells that have low levels of MHC+ self peptides (self regulatory)
NK-T cells
T cell and NK surface markers, kill host cells infected with intracellular bacteria
Plasma cell
First thing engaged with macrophages if infection, informs adaptive immune system what to do, found everywhere
Neutrophils
Phagocytose and kill bacterial (produce antimicrobial peptides)
Eosinophils
Kill invading parasites
Mast cells and basophils
Release TNF, IL-6, IFN in response to bacterial PAMPs
Adaptive immune response
Unique antigen receptor found on each lymphocyte, in infection undergoes clinical expansion, high degree of specificity
Primary lymphoid organ
Bone marrow and Thymus
Secondary lymphoid organ
Spleen (white pulp), lymph node, mucosal surfaces
Antigen presentation
Antigens are internalised and broken down to peptides, associate with newly synthesised class 2 molecules brought to cell surface