Overview Introduction Blood Cell Types Type Description Erythrocyte Red cell responsible for carrying O2 to tissues, and CO2 to lungs Erythropoietin increases RBC production Glucose uptake not affected by insulinLife span of 120 days Most energy produced is via glycolysis Hexose monophosphate (HMP) shunt to produce NAPDH and ribose 5-phosphate Platelets Derived from megakaryocytes Plays a role inhemostasis Endothelial damage leads to platelet aggregation via other platelets and fibrinogen Contains granules that are secreted upon platelet activation dense granules – ADP, Ca2+ α-granules – vWF, fibrinogen, platelet-derived growth factor (PDGF) Mast cells Involved in allergic reaction via a type I hypersensitivity mechanism Granules containing substances such ashistamine and heparin Receptors (FcεR1) on mast cell can bind to IgE IgE binding →cross-linking → degranulation Monocytes When in tissues, it differentiates into macrophages Macrophages Has ability to ingest pathogens, cellular debris, and dead or dying cells Interferon-γ is an important activator of macrophages Antigen presenting abilities via MHC II Involved in granuloma formation (i.e., tuberculosis) Dendritic cell Antigen presenting cell via MHC II Acting as a link between the innate and adaptive immune system White blood cell differential Neutrophils (54 – 62%) if ↑, think bacterial infection ↑ myeloid proliferation due to conditions such as bacterial infections would ↑band cells Band cell = immature neutrophils C5a, IL-8, LTB4 are some molecules that promote chemotaxis in neutrophils to infection or inflammation sites hypersegmented in vitamin B12 or folate deficiency Lymphocytes (25 – 33%) B-cell matures in marrow differentiates into antibody producing cells (plasma cells) when encountering antigen antigen presenting ability via MHC II T-cell matures in thymus cytotoxic T-cell: CD8+ recognize MHC I helpter T-cell: CD4+ recognize MHC II T-cells are activated with CD28 costimulation Monocytes (3 – 7%) Eosinophils (1 – 3%)↑ in conditions such as helminthic infection, neoplasia, Addison disease, and so forth Basophils (0 – 0.75%) involved in allergic reactions granules contain heparin and histamine can be ↑ in chronic myelogenous leukemia (CML)can be helpful in differentiating from leukemoid reaction