Unit Six: Blood Cells, Immunity, and Blood Coagulation Chapter 33: Resistance of the Body to Infection. I. Leukocytes, Granulocytes, the Monocyte-Macrophage System, and Inflammation Guyton and Hall, Textbook of Medical Physiology, 12th edition

Leukocytes (White Blood Cells) General Characteristics Types: neutrophils, basophils, eosinophils, monocytes, lymphocytes (plasma cells) b. Concentrations in the blood White Blood Cell % in Whole Blood Polymorphonuclear Neutrophils 62.0% Polymorphonuclear Eosinophils 2.3% Polymorphonuclear Basophils 0.4% Monocytes 5.3% Lymphocytes 30.0%

Leukocytes (White Blood Cells) Genesis of WBCs Fig. 33.1 Genesis of WBCs

Leukocytes (White Blood Cells) Life Span of WBCs Granulocytes- 4-8 hrs in the blood and 4-5 days in tissues Monocytes- 10-20 hrs in the blood, move into tissues and become macrophages which can live for months Lymphocytes- weeks or months moving from circulation into the tissues and back again Platelets- replaced about every 10 days (30,000 formed per day per microliter of blood

Neutrophils and Macrophages Defend Against Infections WBCs Enter the Tissue Spaces by Diapedsis WBCs Move Through the Tissues by Ameboid Motion WBCs Are Attracted to Inflamed Tissue by Chemotaxis

Neutrophils and Macrophages (cont.) Fig. 33.2

Neutrophils and Macrophages (cont.) Phagocytosis Process Neutrophils Macrophages Phagolysosomes Bactericidal properties

Monocyte-Macrophage Cells System Reticuloendothelial System (RES) Histiocytes Macrophages in the lymph nodes Lungs Kupffer cells Spleen and Bone Marrow

Fig. 33.3 Functional diagram of a lymph node

Fig. 33.4 Kupffer cells lining the liver sinusoids Fig. 33.5 Functional structures of the spleen

Inflammation: Role of Neutrophils and Macrophages Vasodilation of local blood vessels Increased permeability of the capillaries Clotting of fluids in the interstitial spaces Migration of granulocytes and monocytes Swelling of the tissue cells Chemicals released: histamine, bradykinin, serotonin, prostaglandins, complement proteins activated, multiple lymphokines

Inflammation: Role of Neutrophils and Macrophages “Walling-Off” Effect of Inflammation- delay the spread of bacterial or toxins Macrophage and Neutrophil Responses Neutrophil invasion of the inflammed area Acute increase of neutrophils in blood Macrophage invasion into area Increased production of granulocytes and monocytes by the bone marrow

Fig. 33.6 Migration of neutrophils from the blood into the inflamed tissue

Feedback Control of the Macrophage/Neutrophil Responses Inflammation (cont.) Feedback Control of the Macrophage/Neutrophil Responses G-CSF: Granulocyte Colony Stimulating Factor GM-CSF: Granulocyte-Monocyte Colony Stimulating Factor IL-1: Inteleukin 1 M-CSF: Monocyte Colony Stimulating Factor TNF: Tumor Necrosis Factor Fig. 33.7

Eosinophils Eosinophils Weakly phagocytic Prominent in parasitic infections Collect in areas where allergic reactions occur

Basophils Basophils Similar to mast cells Release heparin in the blood Release histamine, bradykinin, and serotonin IgE binds to basophil-release of histamine in allergic reactions

Leukopenia and Leukemia Leukopenia- bone marrow produces few wbcs Caused by irradiation (x-rays or gamma rays) Exposure to drugs and chemicals Leukemia- uncontrolled production of wbcs Types Effects on the body