A major cause of mortality and morbidity after allogeneic hematopoietic stem cell transplantation (HSCT) is graft-versus-host disease (GVHD) , which is caused by engraftment of immunocompetent donor T lymphocytes in an immunologically compromised host who shows histocompatibility differences with the…
Two thirds of patients who need allogeneic hematopoietic stem cell transplantation (HSCT) do not have an available HLA-identical sibling. Alternative sources of hematopoietic stem cells (HSCs) are being increasingly used and include matched unrelated donors, unrelated umbilical cord blood ,…
Allogeneic (from a donor) or autologous (from the same individual) hematopoietic stem cells have been used to cure both malignant and nonmalignant disorders. Autologous transplantation is employed as a rescue strategy after delivering otherwise lethal doses of chemotherapy with or…
Evaluation of the Complement System Richard B. Johnston Keywords hereditary angioedema total hemolytic complement activity CH 50 alternative pathway activity AP 50 Testing for total hemolytic complement activity (CH 50 ) effectively screens for most of the common diseases of the…
Complement is an exquisitely balanced, highly influential system that is fundamental to the clinical expression of host defense and inflammation. The complement system also has the capacity to perform functions beyond host defense, such as promoting phagocytic removal of dying…
Leukocytosis is an elevation in the total leukocyte or white blood cell (WBC) count that is 2 SD above the mean for age (see Chapter 748 ). It is most often caused by elevated numbers of neutrophils (i.e., neutrophilia), although…
Leukopenia refers to an abnormally low number of white blood cells (WBCs) in the circulating blood secondary to a paucity of lymphocytes, granulocytes, or both. Because there are marked developmental changes in normal values for WBC counts during childhood (see…
Neutrophils are the first line of defense against microbial invasion. They arrive at the site of inflammation during the critical 2-4 hr after microbial invasion to contain the infection and prevent hematogenous dissemination. This well-orchestrated process is one of the most…
Eosinophils are distinguished from other leukocytes by their morphology, constituent products, and association with specific diseases. Eosinophils are nondividing, fully differentiated cells with a diameter of approximately 8 µm and a bilobed nucleus. They differentiate from stem cell precursors in the…
Mononuclear phagocytes (monocytes, macrophages) are distributed across all body tissues and play a central role in maintaining immunologic and metabolic homeostasis. They are essential for innate host defense against infection, tissue repair and remodeling, and the antigen-specific adaptive immune response.…