Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Chapter 9 Disorders of White Blood Cells and Lymphoid Tissues

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Blood enters tissues Fluid moves into tissues from capillaries Excess tissue fluid enters lymph vessels and is transported to … Peripheral lymphoid organs, where WBCs respond to pathogens Blood and lymph return to heart through vena cava

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins White Blood Cells or Leukocytes Granulocytes –Neutrophils: primary pathogen-fighting cells –Eosinophils: help control allergic responses; fight parasites –Basophils: release heparin, histamine, and other inflammatory mediators

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins White Blood Cells or Leukocytes (cont.) Lymphocytes –B cells: create antibodies –T cells: control immune response; cell-mediated immunity –Natural killer cells: kill antigenic cells Monocytes/macrophages: antigen-presenting cells; create inflammatory mediators

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Which type of leukocyte works the hardest when you receive a vaccination? a.Eosinophil b.Basophil c.B lymphocyte d.Neutrophil

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer c.B lymphocyte Rationale: A vaccination introduces antigens, causing your body to create antibodies to fight the antigens. B lymphocytes create those antibodies. Eosinophils and basophils are part of the allergic/immune response; neutrophils work to fight infections.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Stem Cells in the Bone Marrow Create the White Blood Cells Pluripotent stem cells Multipotent stem cells Common lymphoid stem cells Common myeloid stem cells

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins common myeloid stem cells committed precursor cells erythrocytesplatelets monocytes and granular leukocytes

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins common lymphoid stem cells committed precursor cells T lymphocytes B natural killer cells

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Multipotent stem cells common lymphoid stem cells common myeloid stem cells committed precursor cells T lymphocytes B natural killer cells committed precursor cells erythrocytesplatelets monocytes and granular leukocytes

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Which type of leukocyte is created in the bone marrow (myeloid)? a.Eosinophil b.Basophil c.Neutrophil d.All of the above

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer d.All of the above Rationale: Granular leukocytes are created in the bone marrow; eosinophils, basophils, and neutrophils are all granular leukocytes.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Scenario A man has cancer and is being given radiation therapy. His doctor has prescribed several other drugs including: –Erythropoietin –Granulocyte-monocyte colony-stimulating factor –Thrombopoietin Question: Why have these drugs been prescribed?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins White Blood Cells

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins White Blood Cell Count White blood cell counts vary between species The denser the population, the more neutrophils The more sexual partners, the more eosinophils Question: What can you infer about diseases in these populations?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins White Blood Cell Deficiencies Leukopenia Neutropenia (agranulocytosis) Aplastic anemia Infectious mononucleosis HIV

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Patients with HIV are immunocompromised. Which type of leukocyte is the best indicator of immune function? a.Neutrophil b.Eosinophil c.T lymphocyte d.Monocyte

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer c.T lymphocyte Rationale: Because T lymphocytes direct the immune response, they are used to evaluate immune function. Patients with HIV are usually treated pharmacologically when their T-cell counts drop below 350 cells/mm 3 ; they are considered to have AIDS when their T-cell counts drop to 200 cells/mm 3.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins WBCs are formed and differentiate in the bone marrow Neoplasms arising here cause leukemias or plasma cell dyscrasias They travel to the lymphoid organs to mature and develop Neoplasms arising here are lymphomas Lymph node

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Leukemias Malignant neoplasms of hematopoietic stem cells In bone marrow Create abnormal white blood cells –Lymphocytic –Myelogenous

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Myelocytic Leukemias Mutation of myeloid cell line Overproduction of abnormal monocytes or granulocytes Production of other cell types decreases Multipotent stem cells common lymphoid stem cells mutation in myeloid stem cells neoplastic committed precursor cells abnormal monocytes or granular leukocytes neoplastic myeloid stem cells

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphocytic Leukemias Mutation of lymphoid cell line Overproduction of abnormal immune cells Production of other cell types decreases Multipotent stem cells mutation in lymphoid stem cells common myeloid stem cells neoplastic committed precursor cells abnormal B or T lymphocytes or Natural Killer cells neoplastic B or T lymphocytes or natural killer cells neoplastic lymphoid stem cells

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Leukemias What is the difference between: Acute vs. chronic Lymphocytic vs. myelogenous

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Leukemias Affect Bone Marrow Activity Question: How would this cause: –Bone pain and risk of fractures? –Anemia? –Thrombocytopenia? –Immune suppression?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Scenario Abnormal WBCs are produced and they: Release inflammatory mediators Infiltrate peripheral lymphoid organs Increase blood viscosity Create waste products Question: What signs and symptoms will result?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Scenario A child develops night sweats and nosebleeds. He appears pale, weak, and fatigued Cervical lymph nodes are enlarged Blast count is elevated After chemotherapy, he develops hyperkalemia Question: Why did this happen?

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphomas Hodgkin lymphoma –Malignant B cells invade lymphoid organs Non-Hodgkin lymphoma –B cell –T cell

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Myeloma Abnormal B cells –Can form tumors Produce abnormal antibodies –Immune depression –Proteins increase blood viscosity –Infiltrate organs Proliferation of osteoclasts –Break down bone

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Tell whether the following statement is true or false. Hodgkin lymphoma has a better prognosis than non- Hodgkin lymphoma.

Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer True Rationale: Non-Hodgkin lymphoma originates from malignancies in both T and B lymphocytes, whereas Hodgkin malignancies originate in B cells (a specific type called the Reed-Sternberg cell). Therefore, more immune function is lost in non-Hodgkin lymphoma, and the prognosis is not as good.