3a Flashcards
What are the two stages of the innate immune response?
Immediate innate phase 1st stage. Macrophages. Chemical defenses: antimicrobial proteins and peptides, complements, and cellular defense: phagocytosis.’
Induced innate response: 2nd stage-NEUTROPHILS and phagocytosis induce INFLAMMATION
What are the two aspects of the immediate innate phase?
chemical and cellular defenses. (chemical: antimicrobial proteins and peptides & complements), cellular defense(phagocytosis)
What are PAMPs, DAMPs, and PRRs?
Pathogen associated molecular patterns,pattern recognition receptors, damage-associated-patterns. PRRs recognize PAMps and DAMPs to target antigens and damage self-structures for clearance.
What are opsonin and opsonin receptors and what are they?
Proteins that play a crucial role in the immune system by binding to substances and marking them for phagocytosis.
Collagen-domain receptors, complement receptors, immunoglobulin receptors.
What are the four major groups of PRRs?
Free receptors in the serum and tissue: MBL bind to special carbohydrates.
Free meaning running in the blood stream.
Membrane-bound phagocytic receptors: CLRs, scavenger receptors
Membrane-bound signaling receptors: Toll-like receptors (TLRs)
Cytoplasmic signaling receptors: cell signlaing pathways are captivated→gene expression→production and secretion of cytokines, contributing to innate/inflammatory responses.
What are the two categories of phagocytic receptors and their members?
PRRs: ex c-type lectin receptors(CLRs) bind to carbohydrates-mannose receptors-nannan ligand
Scavenger as receptor: lipoplysaccharides and lipoteichoic acid as the ligand.
Opsonin receptors categories are collagen-domain receptor, complement receptors, immunoglobulin receptors
Complement receptor ex includes CR1 which binds to C3B, ligand includes complement components and fragments.
Immunoglobulin receptors gave the ligands IgA and IgG anditbodies and C-reactive proteins.
binding of PRRs and opsonin receptors
Phagocytic receptors bin directly (PRRs) and indirectly (opsonin receptors) to microbes.
Creation of a phagolysosome occurs when engulfed
engulfed microbes(from phagocytosis) fuse with lysosomes or granules to create an acidified phagolysosome.
What happens in the phagolysosome?-
the ingested material is broken down by lysosomal hydrolases.
What are the phagocytes and their functions?-
Macrophages: Macrophages residing in tissues throughout the body are among the first cells to encounter and respond to pathogens ‘
Neutrophils: typically the first leukocytes to be recruited to an inflammatory site
Dendritic cells- ingest/digest and present pathogen to T cells
What is the purpose of the bactericidal agent produced or released by the phagocytes after the uptake of the microorganisms?-
It is toxic to microbes and can act directly in the phagolysosome. Also activates the acid hydrolases that degrade the contents of the vacuole.
Acidifcication pH and products
3.5-4.0, bacteriostatic or bactericidal
