Lecture 9: White Blood Cells Flashcards
What are white blood cells?
All WBCs (leukocytes) have a nucleus but no hemoglobin
What WBC are granulocytes?
Granulocytes: neutrophils, eosinophils, and basophils which is based cytoplasmic granules made visible by staining
What WBC are agranular?
Agranular: monocytes and lymphocytes which is based cytoplasmic granules made visble by staining
Are WBCs less or more numerous than RBCs?
WBCs are less numerous than RBCs (1 WBC for every 700 RBC)
Are the total WBC population circulating in the blood more or less in time?
~2% of total WBC population is in circulating blood at any time–rest in lymphatic fluid, skin, lungs, lymph nodes & spleen.
What disease causes high white blood cell count?
Leukocytosis is a high white blood cell count–infection, strenuous exercise, anesthesia, or surgery
What disease causes low white blood cell count?
Leukopenia is low white blood cell count–radiation, septic shock or chemotherapy
What is WBC emigration?
WBCs roll along endothelium, stick to it & squeeze between cells.
What are the functions of selectins?
Adhesion molecules help WBCs stick to endothelium, and they are displayed near the site of injury.
What are the functions of integrins?
They are found on neutrophils and they assist in movement through vessel wall.
What are the functions of Neutrophil?
Fastest response of all WBCs to bacteria, which is directed against bacteria.
What protein is released of WBC that acts like antibiotics & poke holes in bacterial cell walls destroying them?
Defensin
What protein is released that helps with digest/destroying of bacteria?
Lysozymes
What strong protein is realsed that destroys bacteria?
Oxidants (e.g., H2O2)
What is Eosinophil function?
They leave capillaries to enter tissue fluid and release histaminase, which slows down inflammation caused by basophils.
They also attack parasitic worms–and phagocytes antibody-antigen complexes.
What is Basophil function?
Inolved in inflammatory and allergic reactions which leaves capillaries & enter connective tissue as mast cells.
What protein are released for Basophil cells?
Heparin–heightens the inflammatory response
Histamine–increasing blood flow
Serotonin–often results in hypersensitivity (allergic) reactions
What is the function of B cells lymphotcyte?
Destory bacteria and their toxins and then they turn into plasma cells that produce antibodies
What is the function of T cells lymphotocyte?
Attack viruses, fungi, transplanted organs, cancer cells, & some bacteria.
What is the function of natural killer cells lymphocyte?
Attack many different mircrobes & some tumor cells as well as destory foreign invaders by direct attack.
What are the functions of Monocyte?
They take longer to get to a site of infection but arrive in larger numbers and then they become wandering macrophages once they leave the capillaries.
Once the monocyte become wandering marcrophages, what action do they do to the cell?
Destory microbes and clean up dead tissue following an infection.
What is Phagocytes?
“cell eating” of bacteria, performed avidly by neutrophils and monocytes.
What is involved in the process of phagocytes?
Chemotaxis, adherence & ingestion, and destruction.
Is it neutrophil, basophil, or eosinphil that have weaker phagocytic activity?
Eosinophil
What is Chemotaxis?
Attraction of phagocytic cells to the site of infection and the chemcials are released by the pathogen and/or the infected cell attract the phagocytes.
What is Adherence?
Fusion of phagocyte to the pathogen’s membrane with indegestion by pseudopodia, resulting in a phagosome.
What are the steps of destruction of a WBC?
1) Initiated when the phagosome fuses with lysosome
2) Results ina “phago-lysosome”
3) Lysozyme is released and destorys the membrane of the pathogen
4) Fragments of the dead pathogen are removed from the cell by excocytosis
What clincal test is used to measure the changes in numbers of circulatin WBCs (% of each type)?
Differential White Blood Cell Count
What is the Normal Range of WBC Counts?
Normal WBC Counts
Neutrophils 60-70% (up if bacterial infection)
Lymphocyte 20-25% (up if viral infection)
Monocyte 3-8% (up if fungal/viral infection)
Eosinophil 2-4% (up if parasite or allergy reaction)
Basophil
What is Bone Marrow Transplant?
Intravenous transfer of healthy bone marrow
What is the procedure of bone marrow?
Destorys sick bone marrow with radiation & chemotherapy–put sample of donor marrow into patients vein for re-seeding of bone marrow and success depends on histocompatiability of donor and recipient.
What type of disease are insisted with bone marrow transplant?
Leukemia, sickle cell, breatst, ovarian, or testicular cancer, lymphoma, or aplastic anemia.
