pathogens pathogens Neutrophils Eosinophils PMN/ Basophils - PowerPoint PPT Presentation

Recognition of Recognition of extracellular extracellular pathogens pathogens

Neutrophils Eosinophils PMN/ Basophils Granulocytes Mast cells Myeloid Innate Monocytes/ Macrophages Dendritic cells Mononuclear cells NK cells Lymphoid CD8 + Tc lymphocytes CD4 + Th lymphocytes Adaptive B lymphocytes

eg. eg. macrophages macrophages PRR PRR PAMP PAMP

Production of acute phase proteins by the liver in response to interleukin-6 (IL-6) IL-6 Liver C-reactive Mannan- Other acute phase proteins, eg: protein binding SAP lectin SP-A SP-B Fibrinogen

Examples of Pattern Recognition Receptors (PRRs) expressed by macrophages Mannose receptor LPS receptor Glucan receptor Scavenger receptor

Toll-like receptors (TLRs) Peptidoglycans (Gram +) Lipoproteins Lipopolysaccharides (Gram -) Lipopolysaccharides Lipoteichoic acids (Gram +) GPI ( T. cruzi ) RS virus F protein Zymosan (Yeast) CD14 TLR2 Flagellin TLR1 TLR4 TLR2 TLR6 TLR5 TLR7 ssRNA G-rich dsRNA oligonucs TLR3 TLR8 Unmeth CpG DNA TLR9 Plasma Endosome membrane

eg. eg. Antigen Antigen B lymphocytes B lymphocytes receptor receptor Antigen Antigen

Principles of vaccination illustrated by immunization with tetanus toxoid Infection Immunization with tetanus with tetanus toxoid bacterium Antibody response to tetanus toxin Time Naïve Memory lymphocytes lymphocytes present present

Antigen combining site V H Fab Heavy chain Light chain Fc Classes/isotypes: IgM; IgG (1, 2, 3, 4); IgA (1, 2); IgE; (IgD) Heavy chains: µ , γ , α , ε , δ Light chains: κ , λ

C µ 1 C ε 1 C µ 1 C ε 1 Class IgM IgE C µ 2 C µ 2 C ε 2 C ε 2 Switch C µ 3 C µ 3 C ε 3 C ε 3 C ε 4 C µ 4 C µ 4 C ε 4

Antibody isotypes: distribution IgM (pentamers) blood IgG (monomers) blood, tissues, placental transfer IgA blood/tissues (monomers) mucosal secretions and milk (dimers) IgE (monomers) tissues (bound to mast cells)