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Lymphoproliferative Disorders
Lymphoproliferative disorders (LPDs) refer to a specific class of diagnoses, comprising a group of several conditions, in which lymphocytes are produced in excessive quantities. These disorders primarily present in patients who have a compromised immune system. Due to this factor, there are instances of these conditions being equated with "immunoproliferative disorders"; although, in terms of nomenclature, lymphoproliferative disorders are a subclass of immunoproliferative disorders—along with hypergammaglobulinemia and paraproteinemias. Lymphoproliferative disorders (examples) * Follicular lymphoma * chronic lymphocytic leukemia * acute lymphoblastic leukemia * hairy cell leukemia * Hemophagocytic lymphohistiocytosis (HLH) * B-cell lymphomas * T-cell lymphomas * multiple myeloma * Waldenström's macroglobulinemia * Wiskott–Aldrich syndrome * Langerhans cell histiocytosis (LCH) * Lymphocyte-variant hypereosinophilia * Pityriasis Lichenoides (PL, PLC, PLVA) * post-tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematology
Hematology ( always spelled haematology in British English) is the branch of medicine concerned with the study of the cause, prognosis, treatment, and prevention of diseases related to blood. It involves treating diseases that affect the production of blood and its components, such as blood cells, hemoglobin, blood proteins, bone marrow, platelets, blood vessels, spleen, and the mechanism of coagulation. Such diseases might include hemophilia, blood clots ( thrombus), other bleeding disorders, and blood cancers such as leukemia, multiple myeloma, and lymphoma. The laboratory analysis of blood is frequently performed by a medical technologist or medical laboratory scientist. Specialization Physicians specialized in hematology are known as hematologists or haematologists. Their routine work mainly includes the care and treatment of patients with hematological diseases, although some may also work at the hematology laboratory viewing blood films and bone marrow slides unde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Cell
A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their cell surface. T cells are born from hematopoietic stem cells, found in the bone marrow. Developing T cells then migrate to the thymus gland to develop (or mature). T cells derive their name from the thymus. After migration to the thymus, the precursor cells mature into several distinct types of T cells. T cell differentiation also continues after they have left the thymus. Groups of specific, differentiated T cell subtypes have a variety of important functions in controlling and shaping the immune response. One of these functions is immune-mediated cell death, and it is carried out by two major subtypes: CD8+ "killer" and CD4+ "helper" T cells. (These are named for the presence of the cell surface proteins CD8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B Cell
B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or inserted into the plasma membrane where they serve as a part of B-cell receptors. When a naïve or memory B cell is activated by an antigen, it proliferates and differentiates into an antibody-secreting effector cell, known as a plasmablast or plasma cell. Additionally, B cells present antigens (they are also classified as professional antigen-presenting cells (APCs)) and secrete cytokines. In mammals, B cells mature in the bone marrow, which is at the core of most bones. In birds, B cells mature in the bursa of Fabricius, a lymphoid organ where they were first discovered by Chang and Glick, which is why the 'B' stands for bursa and not bone marrow as commonly believed. B cells, unlike the other two classes of lymphocytes, T cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphocytosis
Lymphocytosis is an increase in the number or proportion of lymphocytes in the blood. Absolute lymphocytosis is the condition where there is an increase in the lymphocyte count beyond the normal range while relative lymphocytosis refers to the condition where the proportion of lymphocytes relative to white blood cell count is above the normal range. In adults, absolute lymphocytosis is present when the lymphocyte count is greater than 5000 per microliter (5.0 x 109/L), in older children greater than 7000 per microliter and in infants greater than 9000 per microliter. Lymphocytes normally represent 20% to 40% of circulating white blood cells. When the percentage of lymphocytes exceeds 40%, it is recognized as relative lymphocytosis. Causes Lymphocytosis is a feature of infection, particularly in children. In the elderly, lymphoproliferative disorders, including chronic lymphocytic leukemia and lymphomas, often present with lymphadenopathy and a lymphocytosis. Causes of absolute ly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclonal
Monoclonality refers to the state of a line of cells that have been derived from a single clonal origin. Thus "monoclonal cells" can be said to form a single clone. The term ''monoclonal'' comes from the Ancient Greek ''monos'', meaning "alone" or "single", and ''klon'', meaning "twig". The process of replication can occur ''in vivo'', or may be stimulated ''in vitro'' for laboratory manipulations. The use of the term typically implies that there is some method to distinguish between the cells of the original population from which the single ancestral cell is derived, such as a random genetic alteration, which is inherited by the progeny. Common usages of this term include: * Monoclonal antibody: A single hybridoma cell, which by chance includes the appropriate V(D)J recombination to produce the desired antibody, is cloned to produce a large population of identical cells. In informal laboratory jargon, the monoclonal antibodies isolated from cell culture supernatants of these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphocyte
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic adaptive immune system, adaptive immunity), and B cells (for humoral immunity, humoral, antibody-driven adaptive immune system, adaptive immunity). They are the main type of cell found in lymph, which prompted the name "lymphocyte". Lymphocytes make up between 18% and 42% of circulating white blood cells. Types The three major types of lymphocyte are T cell A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell r ...s, B cells and Natural killer cell, natural killer (NK) cells. Lymphocytes can be identified by their large nucleus. T cells and B cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-linked Lymphoproliferative Disease
X-linked lymphoproliferative disease (also known as Duncan disease or Purtilo syndrome and abbreviated as XLP) is a lymphoproliferative disorder, usually caused by SH2DIA gene mutations in males. XLP-positive individuals experience immune system deficiencies that render them unable to effectively respond to the Epstein-Barr virus (EBV), a common virus in humans that typically induces mild symptoms or infectious mononucleosis (IM) in patients. There are two currently known variations of the disorder, known as XLP1 (XLP Type 1) and XLP2. XLP1 is estimated to occur in approximately one in every million males, while XLP2 is rarer, estimated to occur in one of every five million males. Due to therapies such as chemotherapy and stem cell transplants, the survival rate of XLP1 has increased dramatically since its discovery in the 1970s. Presentation In boys with X-linked lymphoproliferative disorder, the inability to mount an immune response to EBV may lead to death via hemophagocytic ly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Castleman Disease
Castleman disease (CD) describes a group of rare lymphoproliferative disorders that involve enlarged lymph nodes, and a broad range of inflammatory symptoms and laboratory abnormalities. Whether Castleman disease should be considered an autoimmune disease, cancer, or infectious disease is currently unknown. Castleman disease includes at least three distinct subtypes: unicentric Castleman disease (UCD), human herpesvirus 8 associated multicentric Castleman disease (HHV-8-associated MCD), and idiopathic multicentric Castleman disease (iMCD). These are differentiated by the number and location of affected lymph nodes and the presence of human herpesvirus 8, a known causative agent in a portion of cases. Correctly classifying the Castleman disease subtype is important, as the three subtypes vary significantly in symptoms, clinical findings, disease mechanism, treatment approach, and prognosis. All forms involve overproduction of cytokines and other inflammatory proteins by the body ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autoimmune Lymphoproliferative Syndrome
Autoimmune lymphoproliferative syndrome (ALPS) is a form of lymphoproliferative disorder (LPDs). It affects lymphocyte apoptosis. It is a rare genetic disorder of abnormal lymphocyte survival caused by defective Fas mediated apoptosis. Normally, after infectious insult, the immune system down-regulates by increasing Fas expression on activated B and T lymphocytes and Fas-ligand on activated T lymphocytes. Fas and Fas-ligand interact to trigger the caspase cascade, leading to cell apoptosis. Patients with ALPS have a defect in this apoptotic pathway, leading to chronic non-malignant lymphoproliferation, autoimmune disease, and secondary cancers. Signs and symptoms All people with ALPS have signs of lymphoproliferation, which makes it the most common clinical manifestation of the disease. The increased proliferation of lymphoid cells can cause the size of lymphoid organs such as the lymph nodes and spleen to increase ( lymphadenopathy and splenomegaly, present in respectively ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post-transplant Lymphoproliferative Disorder
Post-transplant lymphoproliferative disorder (PTLD) is the name given to a B cell proliferation due to therapeutic immunosuppression after organ transplantation. These patients may develop infectious mononucleosis-like lesions or polyclonal polymorphic B-cell hyperplasia. Some of these B cells may undergo mutations which will render them malignant, giving rise to a lymphoma. In some patients, the malignant cell clone can become the dominant proliferating cell type, leading to frank lymphoma, a group of B cell lymphomas occurring in immunosuppressed patients following organ transplant. Signs and symptoms Symptoms of PTLD are highly variable and nonspecific, and may include fever, weight loss, night sweats, and fatigue. Symptoms may be similar to those seen in infectious mononucleosis (caused by EBV). Pain or discomfort may result from lymphadenopathy or mass effect from growing tumors. Dysfunction may occur in organs affected by PTLD. Lung or heart involvement may result in shortne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
