IMMU 2 mobile cells of innate immune system

Pattern recognition receptors

• occurs when molecules located on pathogens or damaged cells bind to PRRS

• hundreds of different types

• mostly on sentinel cells

• also neutrophiles

• circulate within blood bloodstream

sentinel cells found on

• macrophages

• dendritic cells

• mast cells

Sentinel cells recognize

• essential components of pathogens

• stimulate inflammation or anti paracitc

• also help with adaptive immunity

sentinel cells

• found on potential entry points

• activate immunity

• attract additional mobile defences when needed

• activated by PRR, IgE

tissue sentinel cells

• macrophages

• dendritic cell/ dendritic macrophage

• mast cells

monocyte

• present in blood

• undivided nucleus

• pleomorphic shape

monocyte receptor types

• PRR

• antibody receptors

monocyte functions

• phagocytic (remove dying neutrophils)

• sentinel cells (release mediators)

• migrate into tissue and become macrophage or dendritic cells

macrophage

• many are derived from blood monocytes

• most important type of sentinel cells

• phagocytic

• found and stay in tissue

• recognize and react to bacteria, viruses, neutrophils, dead and damaged cells

dendritic cells

• derived from monocytes or lymphoid cells

• sentinel cell

• phagocytic

• found in tissue

basophils

• WBC found in circulation

• basophilic (blue) staining granules

mast cells

• found in tissue

• some arrise from bone marrow, blood basophils, others from bone marrow

sentinel cells

igE

• Antibody that binds strongly to basophils and mast cells

neutrophils

• PMS (polymorphonuclear neutrophils)

• granulic cells

• contain antibacterial granules

• major WBC

• short life (days)

• highly mobile

receptors 3 types

• PRR for bacterial antigens

• antibody receptors

• complement receptors

  • most found in blood

  • phagocytose bacteria and other small particles

  • destroy ingested material

PRR

• recognise antigens common to groups or microbes or damaged tissue

antigen

a substance that will initiate an immune response

antibody

a protein that binds to a specific antigen

antibody receptors

recognise igG antibodies that have bound to an antigen

complement receptors

• a group of blood proteins that are activated by a pathogen

eosinophils

• lobulated with orange/ red granules

• attracted by chemicals

• proteins which destroy nearby tissue

• peroxides

• enzymes

NK lymphocytes

• mononuclear

• circulate in blood and tissue

• apoptosis

• lysing the cell