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CD34
CD34 is a transmembrane phosphoglycoprotein protein encoded by the CD34 gene in humans, mice, rats and other species. CD34 derives its name from the cluster of differentiation protocol that identifies cell surface antigens. CD34 was first described on hematopoietic stem cells independently by Civin et al. and Tindle et al. as a cell surface glycoprotein and functions as a cell-cell adhesion factor. It may also mediate the attachment of hematopoietic stem cells to bone marrow extracellular matrix or directly to stromal cells. Clinically, it is associated with the selection and enrichment of hematopoietic stem cells for bone marrow transplants. Due to these historical and clinical associations, CD34 expression is almost ubiquitously related to hematopoietic cells; however, it is actually found on many other cell types as well. Function The CD34 protein is a member of a family of single-pass transmembrane sialomucin proteins that show expression on early haematopoietic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatofibrosarcoma Protuberans
Dermatofibrosarcoma protuberans (DFSP) is a rare locally aggressive malignant cutaneous soft-tissue sarcoma. DFSP develops in the connective tissue cells in the middle layer of the skin (dermis). Estimates of the overall occurrence of DFSP in the United States are 0.8 to 4.5 cases per million persons per year. In the United States, DFSP accounts for between 1 and 6 percent of all soft-tissue sarcomas and 18 percent of all cutaneous soft-tissue sarcomas. In the Surveillance, Epidemiology, and End Results, Surveillance, Epidemiology and End Results (SEER) tumor registry from 1992 through 2004, DFSP was second only to Kaposi's sarcoma, Kaposi sarcoma. Presentation Dermatofibrosarcoma protuberans begins as a minor firm area of skin most commonly about to 1 to 5 cm in diameter. It can resemble a bruise, birthmark, or pimple. It is a slow-growing tumor and is usually found on the torso but can occur anywhere on the body. About 90% of DFSPs are low-grade sarcomas. About 10% are mix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cluster Of Differentiation
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), 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 surface mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Cell Fibroblastoma
Giant cell fibroblastoma (GCF) is a rare type of soft-tissue tumor marked by painless nodules in the dermis (the inner layer of the two main layers of tissue that make up the skin) and subcutaneous (beneath the skin) tissue. These tumors may come back after surgery, but they do not spread to other parts of the body. They occur mostly in boys. GCF tumor tissues consist of bland spindle-shaped or stellate-shaped cells interspersed among multinucleated giant cells. GCF tumors are closely related to dermatofibrosarcoma protuberans (DFSP) and dermatofibrosarcoma protuberans, fibrosarcomatous (DFSP-FS) (also termed fibrosarcomatous dermatofibrosarcoma protuberans) tumors. The World Health Organization (2020) classified these three tumors as different tumors in the category of fibroblastic and myofibroblastic tumors with GCF and DFSP sub-classified as benign but aggressive tumors and DFSP-FS subclassified as a rarely metastasizing tumor. However, The three tumor types may contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematopoietic Stem Cell
Hematopoietic stem cells (HSCs) are the stem cells that give rise to other blood cells. This process is called haematopoiesis. In vertebrates, the first definitive HSCs arise from the ventral endothelial wall of the embryonic aorta within the (midgestational) aorta-gonad-mesonephros region, through a process known as endothelial-to-hematopoietic transition. In adults, haematopoiesis occurs in the red bone marrow, in the core of most bones. The red bone marrow is derived from the layer of the embryo called the mesoderm. Haematopoiesis is the process by which all mature blood cells are produced. It must balance enormous production needs (the average person produces more than 500 billion blood cells every day) with the need to regulate the number of each blood cell type in the circulation. In vertebrates, the vast majority of hematopoiesis occurs in the bone marrow and is derived from a limited number of hematopoietic stem cells that are multipotent and capable of extensive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem Cells
In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can change into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of cell in a cell lineage. They are found in both embryonic and adult organisms, but they have slightly different properties in each. They are usually distinguished from progenitor cells, which cannot divide indefinitely, and precursor or blast cells, which are usually committed to differentiating into one cell type. In mammals, roughly 50 to 150 cells make up the inner cell mass during the blastocyst stage of embryonic development, around days 5–14. These have stem-cell capability. ''In vivo'', they eventually differentiate into all of the body's cell types (making them pluripotent). This process starts with the differentiation into the three germ layers – the ectoderm, mesoderm and endoderm – at the gastrulation stage. However, when t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-selectin
L-selectin, also known as CD62L, is a cell adhesion molecule found on the cell surface of leukocytes, and the blastocyst. It is coded for in the human by the ''SELL'' gene. L-selectin belongs to the selectin family of proteins, which recognize sialylated carbohydrate groups containing a Sialyl LewisX (sLeX) determinant. L-selectin plays an important role in both the innate and adaptive immune responses by facilitating leukocyte-endothelial cell adhesion events. These tethering interactions are essential for the trafficking of monocytes and neutrophils into inflamed tissue as well as the homing of lymphocytes to secondary lymphoid organs. L-selectin is also expressed by lymphoid primed hematopoietic stem cells and may participate in the migration of these stem cells to the primary lymphoid organs. In addition to its function in the immune response, L-selectin is expressed on embryonic cells and facilitates the attachment of the blastocyst to the endometrial endothelium during human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stromal Cell
Stromal cells, or mesenchymal stromal cells, are differentiating cells found in abundance within bone marrow but can also be seen all around the body. Stromal cells can become connective tissue cells of any organ, for example in the uterine mucosa (endometrium), prostate, bone marrow, lymph node and the ovary. They are cells that support the function of the parenchymal cells of that organ. The most common stromal cells include fibroblasts and pericytes. The term ''stromal'' comes from Latin , "bed covering", and Ancient Greek , , "bed". Stromal cells are an important part of the body's immune response and modulate inflammation through multiple pathways. They also aid in differentiation of hematopoietic cells and forming necessary blood elements. The interaction between stromal cells and tumor cells is known to play a major role in cancer growth and progression. In addition, by regulating local cytokine networks (e.g. M-CSF, LIF), bone marrow stromal cells have been describ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Cell
T cells (also known as T lymphocytes) are an important part 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 receptor, 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: Cytotoxic T cell, CD8+ "killer" (cytotoxic) and T helper cell, CD4+ "helper" T cells. (These are named for the presen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multipotent Hematopoietic Stem Cell
Cell potency is a cell's ability to differentiate into other cell types. The more cell types a cell can differentiate into, the greater its potency. Potency is also described as the gene activation potential within a cell, which like a continuum, begins with totipotency to designate a cell with the most differentiation potential, pluripotency, multipotency, oligopotency, and finally unipotency. Totipotency Totipotency () is the ability of a single cell to divide and produce all of the differentiated cells in an organism. Spores and zygotes are examples of totipotent cells. In the spectrum of cell potency, totipotency represents the cell with the greatest differentiation potential, being able to differentiate into any embryonic cell, as well as any extraembryonic tissue cell. In contrast, pluripotent cells can only differentiate into embryonic cells. A fully differentiated cell can return to a state of totipotency. The conversion to totipotency is complex and not full ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megakaryocytes
A megakaryocyte () is a large bone marrow cell with a lobated nucleus that produces blood platelets (thrombocytes), which are necessary for normal clotting. In humans, megakaryocytes usually account for 1 out of 10,000 bone marrow cells, but can increase in number nearly 10-fold during the course of certain diseases. Owing to variations in combining forms and spelling, synonyms include megalokaryocyte and megacaryocyte. Structure In general, megakaryocytes are 10 to 15 times larger than a typical red blood cell, averaging 50–100 μm in diameter. During its maturation, the megakaryocyte grows in size and replicates its DNA without cytokinesis in a process called endomitosis. As a result, the nucleus of the megakaryocyte can become very large and lobulated, which, under a light microscope, can give the false impression that there are several nuclei. In some cases, the nucleus may contain up to 64N DNA, or 32 copies of the normal complement of DNA in a human cell. The cytoplas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Differentiation
Cellular differentiation is the process in which a stem cell changes from one type to a differentiated one. Usually, the cell changes to a more specialized type. Differentiation happens multiple times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. Differentiation continues in adulthood as adult stem cells divide and create fully differentiated daughter cells during tissue repair and during normal cell turnover. Some differentiation occurs in response to antigen exposure. Differentiation dramatically changes a cell's size, shape, membrane potential, metabolic activity, and responsiveness to signals. These changes are largely due to highly controlled modifications in gene expression and are the study of epigenetics. With a few exceptions, cellular differentiation almost never involves a change in the DNA sequence itself. Metabolic composition, however, gets dramatically altered where st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PreB-ALL
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 and bone marrow. It is the most common type of acute lymphoblastic leukemia Acute lymphoblastic leukemia (ALL) is a cancer of the Lymphocyte, lymphoid line of blood cells characterized by the development of large numbers of lymphoblast, immature lymphocytes. Symptoms may include feeling tired, pale skin color, fever, ... (ALL). It is sometimes additionally classified as a lymphoma, as designated ''leukemia/lymphoma''. ALL is the most prevalent childhood malignancy, with precursor B-cell ALL (B-ALL) accounting for approximately 75–80% of newly diagnosed pediatric ALL cases. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
