Neutrophils emigratefrist and monocytesmove late usinga similar meachanism(as'VCAM' in monocytes andVLA -4 in neutrophilstake 24hrs to be expressed)Lymphocytes, esoinophilsand plasma cells mayfollow later
'Diapedes'neutrophils squeezebetween neighbouringendothelial cells andcross the basementmembrane bysecreting proteases tobreak it down
Bind tointegrins(e.g. LFA-1)on the neutrophils
Expression ofimmunoglobin-likemolecules (whichbelong to the superfamily e.g.ICAM-1) byendothelial cells
Production ofinflammatoryCytokinesE.g, IL-1 and TNF andCXCL8
Over expressionof P andE-selectin byendothelial cells
Bind tosialylatedglycoproteinlgands on neutrophils
Rolling ofneutrophilsalongendothelium dueto disruptedweakinteractions
Other effects ofcytokines(See inflammatorycytokines flowchart)
movement ofproteins andleukocytes fromblood into tissuefluid space
Fibrinogenconverted tofibrin bythorombin
Forms insolublestrands whichproduce a web tocontain infectionand inflammation
Fromation ofinflammatoryExudate
Monocytesmature to frommarcrophages
'Chemotaxis'All leukocytes arestimulated to migratetowards the infected areaalong CXCL8 gradients
increasedvascularpermeability
Shrinking ofendothelialcells
Histamineblood vesselendothelium
Overxpressionof P-selectin byendothelial cells
Histamine onsmooth musclecells onvascular walls
Histaminereceptors onnerve ending
Mast cellsdegranulate andsecretion preformedhistamine
Recruitment of leukocytes usingcytokines and chemokines
Signalssent tonucleus ofsentinel cell
PAMPrecognisedby PRR onsentinel cell(usuallyresidentmacrophage)
SecreteType llinterferon,IFNY
Activate Naturalkiller (NK)_ cells
Releasegranulescontainingperforinand aporptosisinducinggranzymes
Perforinperforatesmembraneof targetcell andgranzymes enter, inducingapoptosis
'Recognitionof missingself' by NKcells
Down regulationof MajorHistocomptibiliyComplex Class lmolecules
Interferewith viralreplication
Secrete TypeI INterferons(e.g. IFN a &IFNB)
'Antibody DependentCytotoxicity' (ADCC)Antibodies detectedvia Fc Receptors onNK cells
Activation ofplateletactivatingfactor found inthe lipid bilayer
Arachidonicacids inphospholipidbilayerconverted
Lipid inflammatory mediators