Best Immunology Study Guide

Cells: Innate Immunity
Phagocyte – internalize and destroy antigen


Receptors and Ligands
Phagocyte Receptor
Direct
PPRR*
Indirect
FcγR
CR-1 complement receptor
CRP binding site (C-reactive Protein)
* Primitive Pattern Recognition Receptors

Antigen Ligand
PAMPS**
IgG (Fc)
C3b
CRP
** Pathogen Associated Molecular Patterns



Armamentarium o Lysosomal Enzymes
 Lactoferrin – binds iron
 Defensins – permeabalize membranes
 Lysozyme – destroys bacterial wall
 Myeloperoxidase – catalyses reaction to form hypochlorite o Reactive Oxygen Intermediates (ROI’s)
 Hydroxyl Radical
 Hydroxyl Ion
 Superoxide anion
 Hydrogen peroxide (NADPH oxidase activation) o Hypochlorite Ion – reaction catalyzed by Myeloperoxidase o Reactive Nitrogen Intermediates (RNI’s)
 Activation of iNOS



IL-1, IL-6, IL-12, TNF : released after macrophage activation

Eosinophils – destroys helminths (role in allergies)


Receptors and Ligands
Eosinophil Receptor
FcR



Antigen Ligand
IgE (Fc)

Armamentarium o Major Basic Protein (MBP) – membrane disruption o Eosinophilic Cationic Protein (ECP) – membrane pore creation

Natural Killer Cells – destroys infected autologous cells


Receptors and Ligands
NK Cell Receptor

Antigen Ligand

Direct
NK Activating Receptor
Various
Killer Inhibitory Receptor (KIR)
Various
Indirect
FcγR
IgG (Fc)*
* Leads to ADCC (antibody dependent cell mediated cytotoxicity)


Armamentarium o Perforin – causes osmotic lysis o Granzymes - causes apoptosis



IFNγ – released by NK Cells after activation

NOTE: Items in RED were included in the Fall 2007 Midterm

Accessory Cells (Mast Cells/Basophils)


Receptors and Ligands
Accessory Cell Receptor
FcR

IgE (Fc)* - then cross linking with antigen

C5aR

C5a

C4a and C3a Receptor



Counter Molecules

C4a or C3a complement fragments

Cells product – histamine
Kills helminths

Soluble Mediators –