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Lymphoid Leukemia
Lymphoid leukemias are a group of leukemias affecting circulating lymphocytes, a type of white blood cell. The lymphocytic leukemias are closely related to lymphomas of the lymphocytes, to the point that some of them are unitary disease entities that can be called by either name (for example, adult T-cell leukemia/lymphoma). Such diseases are all lymphoproliferative disorders. Most lymphoid leukemias involve a particular subtype of lymphocytes, the B cells. Classification Historically, they have been most commonly divided by the stage of maturation at which the clonal (neoplastic) lymphoid population stopped maturing: * Acute lymphoblastic leukemia * Chronic lymphocytic leukemia However, the influential WHO Classification (published in 2001) emphasized a greater emphasis on cell lineage. To this end, lymphoid leukemias can also be divided by the type of cells affected: * B-cell leukemia * T-cell leukemia * NK-cell leukemia The most common type of lymphoid leukemia is B-cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oncology
Oncology is a branch of medicine that deals with the study, treatment, diagnosis and prevention of cancer. A medical professional who practices oncology is an ''oncologist''. The name's etymological origin is the Greek word ὄγκος (''ónkos''), meaning "tumor", "volume" or "mass". Oncology is concerned with: * The diagnosis of any cancer in a person (pathology) * Therapy (e.g. surgery, chemotherapy, radiotherapy and other modalities) * Follow-up of cancer patients after successful treatment * Palliative care of patients with terminal malignancies * Ethical questions surrounding cancer care * Screening efforts: ** of populations, or ** of the relatives of patients (in types of cancer that are thought to have a hereditary basis, such as breast cancer) Diagnosis Medical histories remain an important screening tool: the character of the complaints and nonspecific symptoms (such as fatigue, weight loss, unexplained anemia, fever of unknown origin, paraneoplasti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Surface Marker
The cluster of differentiation (also known as cluster of designation or classification determinant and often abbreviated as CD) is a protocol used for the identification and investigation of cell surface molecules providing targets for immunophenotyping of cells. In terms of physiology, CD molecules can act in numerous ways, often acting as receptors or ligands important to the cell. A signal cascade is usually initiated, altering the behavior of the cell (see cell signaling). Some CD proteins do not play a role in cell signaling, but have other functions, such as cell adhesion. CD for humans is numbered up to 371 (). Nomenclature The CD nomenclature was proposed and established in the 1st International Workshop and Conference on Human Leukocyte Differentiation Antigens (HLDA), which was held in Paris in 1982. This system was intended for the classification of the many monoclonal antibodies (mAbs) generated by different laboratories around the world against epitopes on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precursor T-cell Lymphoblastic Leukemia
T-lymphoblastic leukemia/lymphoma (WHO 2008), previously labeled precursor T-lymphoblastic leukemia/lymphoma (WHO 2001) is a form of lymphoid leukemia and lymphoma in which too many T-cell lymphoblasts (immature white blood cells) are found in the blood, bone marrow, and tissues, particularly mediastinal lymph nodes. Labeling as leukemia or lymphoma depends on which feature is more pronounced in a given situation, but has no biological or treatment implication. It is uncommon in adults, but represents 15% of childhood acute lymphoblastic leukemia and 90% of lymphoblastic lymphoma. The 2008 terminology dropped "precursor" to avoid linguistic redundancy because the lymphoblast __NOTOC__ A lymphoblast is a modified naive lymphocyte with altered cell morphology. It occurs when the lymphocyte is activated by an antigen (from antigen-presenting cells) and increased in volume by nucleus and cytoplasm growth as well as new mRN ... is an immature precursor cell by definition. Refere ... [...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] |
Hairy Cell Leukemia
Hairy cell leukemia is an uncommon hematological malignancy characterized by an accumulation of abnormal B lymphocytes. It is usually classified as a subtype of chronic lymphocytic leukemia (CLL). Hairy cell leukemia makes up about 2% of all leukemias, with fewer than 2,000 new cases diagnosed annually in North America and Western Europe combined. Hairy cell leukemia (HCL) was originally described as histiocytic leukemia, malignant reticulosis, or lymphoid myelofibrosis in publications dating back to the 1920s. The disease was formally named leukemic reticuloendotheliosis, and its characterization was significantly advanced by Bertha Bouroncle and colleagues at the Ohio State University College of Medicine in 1958. Its common name, which was coined in 1966, is derived from the "hairy" appearance of the malignant B cells under a microscope. Signs and symptoms In HCL, the "hairy cells" (malignant B lymphocytes) accumulate in the bone marrow, interfering with the production of no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B-cell Prolymphocytic Leukemia
B-cell prolymphocytic leukemia, referred to as B-PLL, is a rare blood cancer. It is a more aggressive, but still treatable, form of leukemia. Specifically, B-PLL is a prolymphocytic leukemia (PLL) that affects prolymphocytes – immature forms of B-lymphocytes and T-lymphocytes – in the peripheral blood, bone marrow, and spleen. It is an aggressive cancer that presents poor response to treatment. Mature lymphocytes are infection-fighting immune system cells. B-lymphocytes have two responsibilities: # Production of antibodies – In response to antigens, B-lymphocytes produce and release antibodies specific to foreign substances in order to aid in their identification and elimination phagocytes # Generation of memory cells – Interactions between antibodies and antigens allow B-lymphocytes to establish cellular memories, otherwise known as immunities that allow the body to respond more rapidly and efficiently to previously encountered species Classification It is categorized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD19
B-lymphocyte antigen CD19, also known as CD19 molecule ( Cluster of Differentiation 19), B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12 and CVID3 is a transmembrane protein that in humans is encoded by the gene ''CD19''. In humans, CD19 is expressed in all B lineage cells. Contrary to some early doubts, human plasma cells do express CD19, as confirmed by others. CD19 plays two major roles in human B cells: on the one hand, it acts as an adaptor protein to recruit cytoplasmic signaling proteins to the membrane; on the other, it works within the CD19/CD21 complex to decrease the threshold for B cell receptor signaling pathways. Due to its presence on all B cells, it is a biomarker for B lymphocyte development, lymphoma diagnosis and can be utilized as a target for leukemia immunotherapies. Structure In humans, CD19 is encoded by the 7.41 kilobase ''CD19'' gene located on the short arm of chromosome 16. It contains at least fifteen exons, four that encode ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminal Deoxynucleotidyl Transferase
Terminal deoxynucleotidyl transferase (TdT), also known as DNA nucleotidylexotransferase (DNTT) or terminal transferase, is a specialized DNA polymerase expressed in immature, pre-B, pre-T lymphoid cells, and acute lymphoblastic leukemia/lymphoma cells. TdT adds N-nucleotides to the V, D, and J exons of the TCR and BCR genes during antibody gene recombination, enabling the phenomenon of junctional diversity. In humans, terminal transferase is encoded by the ''DNTT'' gene. As a member of the X family of DNA polymerase enzymes, it works in conjunction with polymerase λ and polymerase μ, both of which belong to the same X family of polymerase enzymes. The diversity introduced by TdT has played an important role in the evolution of the vertebrate immune system, significantly increasing the variety of antigen receptors that a cell is equipped with to fight pathogens. Studies using TdT knockout mice have found drastic reductions (10-fold) in T-cell receptor (TCR) diversity compa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphoblast
__NOTOC__ A lymphoblast is a modified naive lymphocyte with altered cell morphology. It occurs when the lymphocyte is activated by an antigen (from antigen-presenting cells) and increased in volume by nucleus and cytoplasm growth as well as new mRNA and protein synthesis. The lymphoblast then starts dividing two to four times every 24 hours for three to five days, with a single lymphoblast making approximately 1000 clones of its original naive lymphocyte, with each clone sharing the originally unique antigen specificity. Finally the dividing cells differentiate into effector cells, known as plasma cells (for B cells), cytotoxic T cells, and helper T cells. Lymphoblasts can also refer to immature cells which typically differentiate to form mature lymphocytes. Normally lymphoblasts are found in the bone marrow, but in acute lymphoblastic leukemia (ALL), lymphoblasts proliferate uncontrollably and are found in large numbers in the peripheral blood. The size is between 10 and 20 μm. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Leukemia
Acute leukemia or acute leukaemia is a family of serious medical conditions relating to an original diagnosis of leukemia. In most cases, these can be classified according to the lineage, myeloid or lymphoid, of the malignant cells that grow uncontrolled, but some are mixed and for those such an assignment is not possible. Forms of acute leukemia include: * Acute myeloid leukemia ** Acute erythroid leukemia * Acute lymphoblastic leukemia ** T-cell acute lymphoblastic leukemia *** Adult T-cell leukemia/lymphoma *** (Precursor) T-lymphoblastic leukemia/lymphoma * ''Blast crisis'' of chronic myelogenous leukemia Chronic myelogenous leukemia (CML), also known as chronic myeloid leukemia, is a cancer of the white blood cells. It is a form of leukemia characterized by the increased and unregulated growth of myeloid cells in the bone marrow and the accumul ... References {{Set index article Leukemia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precursor B-cell Lymphoblastic Leukemia
Precursor B-cell lymphoblastic leukemia is a form of lymphoid leukemia in which too many B-cell lymphoblasts (immature white blood cells) are found in the blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ... and bone marrow. It is the most common type of acute lymphoblastic leukemia (ALL). It is sometimes additionally classified as a lymphoma, as designated ''leukemia/lymphoma''. Subtypes It consists of the following subtypes: * t(9;22)-BCR/ ABL * t(v;11q23)-MLL rearrangement * t(1;19)-E2A/PBX1 * t(12;21)-ETV/ CBFα t(17;19)-E2A-HLF Molecular Mechanisms One interesting model of precursor B ALL shows aberrant function of a single gene, namely Pax5, as capable to change phenotype of B cells toward precursor cells. Diagnosis t(12;21)-ETV/ CBFα has a better prognosis as compared ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin
An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the pathogen, called an antigen. Each tip of the "Y" of an antibody contains a paratope (analogous to a lock) that is specific for one particular epitope (analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can ''tag'' a microbe or an infected cell for attack by other parts of the immune system, or can neutralize it directly (for example, by blocking a part of a virus that is essential for its invasion). To allow the immune system to recognize millions of different antigens, the antigen-binding sites at both tips of the antibody come in an equally wide variety. In contrast, the remainder of the antibody is relatively constant. It only occurs in a few va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
