Week 3 Immune Regulations + Blood Groups (Incomplete) Flashcards
What are the 3 phases of regulation of immune response?
Phase 1 Immediate response;
Phase 2 Early-induced phase (after 1-2 days);
Phase 3 Late phase with adaptive immune response
(after 5-7 days)
What are some of the physical barriers that make up the immediate response phase?
Skin, mucosal surface of the GI tract, respiratory system, and urogenital system.
What are some of the early antimicrobial peptides that make the physical barriers more effective?
Defensins, cathelicidins. Later on, IgA antibodies help.
How do phagocytes recognize microbes, and what about microbes do they recognize?
Phagocytes use PRR’s (Pattern recognition receptors) to recognize PAMP’s (pathogen associated molecular patterns)
What are some types of PRR’s?
Toll-like receptors (TLR), C-type lectins, Scavenger
receptors, NOD-like receptors
How long does it take for the early-induced phase to begin?
1-2 days
What is the mechanism for early-induced phase activation?
PRR-dependent activation of various cell types, leading to cytokine secretion, secretion of antimicrobial peptides, antigen presentation by APC’s, and cytokine production
What do IFN alpha and beta do?
They are antimicrobial peptides against viral infection
What do lysozymes do?
They are antimicrobial peptides that degrade the bacterial wall
What do interleukin-1 and TNF do?
These are acute-phase cytokines that lead to adhesion receptor upregulation and migration
What does mannose-binding lectin (MBL) do?
Performs complement activation (acute phase cytokine)
What does CRP (C-reactive protein) do?
Opsonization of microbes (acute phase cytokine)
What do endogenous pyrogens do?
Induce fever (acute phase protein)
What do cathelicidins do?
It’s an antimicrobial peptide on mucosal surfaces
What do interferons do?
Inhibit viral replication
Virus infection shows up in which MHC class? What cell type recognizes them?
MHC Class I; Cytotoxic T cells
T helper type 1 cells mainly do what? And type 2?
Th1: activate macrophages, Th2: activate B lymphocytes into plasma or memory cells
When is the late phase with adaptive immune response?
After 5-7 days
What does the mechanism of the late phase with adaptive immune response depend on?
Depends on the microorganism or virus
What are the late responses to viral infection? This also goes for tumor formation
Make a new non-self protein in the infected cell, presentation by MHC Class I, CD8 positive cytotoxic T cell activation, killing of the infected cell
What are the late responses to bacterial infection as well as some viruses?
uptake by APCs, presentation by MHC Class II, CD4 positive helper T cell activation (T h1 or T h2 )
What are the late responses to parasitic worm infection?
extracellular killing
(eosinophil mediated),
MBP – major basic protein release from the granules
What is more effective at killing virus-infected cells, NK cells or T-cell mediated killing?
T-cell mediated killing
