Chapter 3 Flashcards
What cell types are represented by the word “granulocyte”?
Neutrophils, eosinophils, and basophils
What are the three types of circulating immunologic cells?
Granulocytes, lymphocytes, and monocytes
What is the term given to extravascular migration?
Diapedesis
What organelle does a granulocyte contain that makes it well-suited for immunologic response?
Granules containing biologically active substances involved in inflammatory and allergic reactions.
What attracts neutrophils to the endothelial surface and what particular molecules cause diapedesis of neutrophils?
Neutrophils are attracted to selectins lining the vasculature, in particular, neutrophil adhesion molecules of the integrin family initiate diapedesis.
Describe the inflammatory response.
Stimulation of bone marrow to produce and release large numbers of neutrophils.
Bacteria react with plasma factors to produce chemotactic agents.
Other plasma factors attach to bacteria inducing opsonization by phagocytes.
Describe the response of neutrophils to IgG coated bacteria.
Coated bacteria bind to neutrophil causing increased motor activity (respiratory burst).
Prompt ingestion by phagocytosis.
Granular contents are exocytosed into phagocytic vacuole (degranulation).
What combination of biological factors destroys bacteria within neutrophil phagocytic vacuoles?
Proteases, antimicrobial proteins (defensins), reactive oxygen species produced by NADPH oxidase
What enzyme is produced by neutrophils that acts on Cl-, Br-, I-, and SCN-? What are the products?
Myeloperoxidase, it converts these anions into corresponding acids (HOCl, HOBr, HOI, and HSCN) which are potent oxidants.
What similarities do eosinophils share with neutrophils in regards to diapedesis and migration throughout the vasculature?
Attracted to surface of endothelial cells, bind strongly to integrins, enter tissues via diapedesis.
Where are eosinophils most abundant?
Gastrointestinal tract.
What invading organisms do eosinophils specialize in?
Parasites of the GI tract, respiratory and urinary tracts.
What inflammatory molecules do basophils secrete?
Histamine
