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Physiology 12Physiology 12

Blood Contents and Immune FunctionBlood Contents and Immune Function

Germann Ch 22

Blood contentsBlood contents

Erythrocytes = red blood cellsErythrocytes = red blood cellsPurpose, to carry hemoglobin Purpose, to carry hemoglobin

Leukocytes = white blood cellsLeukocytes = white blood cellsPurpose, immune system defensePurpose, immune system defense

Platelets = cell fragmentsPlatelets = cell fragmentsPurpose, clotting factorsPurpose, clotting factors

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Blood contentsBlood contents

Erythrocytes = red blood Erythrocytes = red blood cellscells

Purpose, to carry Purpose, to carry hemoglobin hemoglobin

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Regulation of blood cells is done Regulation of blood cells is done by hormonal factors that by hormonal factors that

influence stem cell developmentinfluence stem cell development

ErythropoietinErythropoietin

HemostasisHemostasis

Prevention of blood lossPrevention of blood loss

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How to prevent blood lossHow to prevent blood loss

Constrict broken vesselsConstrict broken vesselsClot blood around sites Clot blood around sites of injuryof injury

Broken endothelial cells Broken endothelial cells expose collagenexpose collagen

Circulating Von Circulating Von WillebrandWillebrand Factor binds Factor binds collagencollagen

Collagen binding alters Collagen binding alters VWF shape to bind VWF shape to bind plateletsplatelets

Platelets aggregate Platelets aggregate around broken areaaround broken area

The Blood clotting reactionThe Blood clotting reaction

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Stopping blood clottingStopping blood clotting(anticoagulants)(anticoagulants)

NaturalNaturalThrombomodulinThrombomodulin = enzymatic inhibition from = enzymatic inhibition from intact endothelial cellsintact endothelial cells

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Stopping blood clottingStopping blood clotting(anticoagulants)(anticoagulants)

NaturalNaturalThrombomodulinThrombomodulin = enzymatic inhibition from = enzymatic inhibition from intact endothelial cellsintact endothelial cellsAntithrombinAntithrombin III = circulating factor that inhibits III = circulating factor that inhibits clotting factors when bound to heparinclotting factors when bound to heparin

Stopping blood clottingStopping blood clotting(anticoagulants)(anticoagulants)

NaturalNaturalThrombomodulinThrombomodulin = enzymatic inhibition from = enzymatic inhibition from intact endothelial cellsintact endothelial cellsAntithrombinAntithrombin III = circulating factor that inhibits III = circulating factor that inhibits clotting factors when bound to heparinclotting factors when bound to heparin

DrugsDrugsAsprinAsprin = = EicosanoidEicosanoid pathways and pathways and therforetherfore inhibits inhibits thromboxanethromboxane A2A2Oral anticoagulants (Oral anticoagulants (cumadincumadin etc)etc)

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Immune functionImmune function

The body’s cellular defenseThe body’s cellular defense

Nonspecific Immune ResponsesNonspecific Immune Responses

Physical barriersPhysical barriersSkinSkinMucusMucusCoughing and SneezingCoughing and Sneezing

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Nonspecific Immune ResponsesNonspecific Immune Responses

Physical barriersPhysical barriersSkinSkinMucusMucusCoughing and SneezingCoughing and Sneezing

InflamationInflamation--ChemotaxisChemotaxis--PhagocytosisPhagocytosis

MacrophageMacrophage

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Nonspecific Immune ResponsesNonspecific Immune Responses

Physical barriersPhysical barriersSkinSkinMucusMucusCoughing and SneezingCoughing and Sneezing

InflamationInflamation--ChemotaxisChemotaxis--PhagocytosisPhagocytosisComplement systemComplement system

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Nonspecific Immune ResponsesNonspecific Immune Responses

Physical barriersPhysical barriersSkinSkinMucusMucusCoughing and SneezingCoughing and Sneezing

InflamationInflamation--ChemotaxisChemotaxis--PhagocytosisPhagocytosisComplement systemComplement systemInterferon ProductionInterferon Production

Viruses

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Specific immune DefensesSpecific immune Defenses

Antigen recognition by antibodiesAntigen recognition by antibodies

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How do B cells know what How do B cells know what antibodies to produce?antibodies to produce?

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Where does all this exchange take Where does all this exchange take place?place?

LymphLymphSpleenSpleenBloodBloodInfected tissueInfected tissue

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What’s the end result of a specific What’s the end result of a specific immune response?immune response?

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EndEnd

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