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Peptide Vaccine
Peptide-based synthetic vaccines (epitope vaccines) are subunit vaccines made from peptides. The peptides mimic the epitopes of the antigen that triggers direct or potent immune responses. Peptide vaccines can not only induce protection against infectious pathogens and non-infectious diseases but also be utilized as therapeutic cancer vaccines, where peptides from tumor-associated antigens are used to induce an effective anti-tumor T-cell response. History The traditional vaccines are the whole live or fixed pathogens. The second generation of vaccines is mainly the protein purified from the pathogen. The third generation of vaccines is the DNA or plasmid that can express the proteins of the pathogen. Peptide vaccines are the latest step in the evolution of vaccines. Advantages and disadvantages Compared with the traditional vaccines such as the whole fixed pathogens or protein molecules, the peptide vaccines have several advantages and disadvantages. Advantages: * The v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subunit Vaccine
A subunit vaccine is a vaccine that contains purified parts of the pathogen that are antigenic, or necessary to elicit a protective immune response. A "subunit" vaccine doesn't contain the whole pathogen, unlike live attenuated or inactivated vaccine, but contains only the antigenic parts such as proteins, polysaccharides or peptides. Because the vaccine doesn't contain "live" components of the pathogen, there is no risk of introducing the disease, and is safer and more stable than vaccine containing whole pathogens. Other advantages include being well-established technology and being suitable for immunocompromised individuals. Disadvantages include being relatively complex to manufacture compared to some vaccines, possibly requiring adjuvants and booster shots, and requiring time to examine which antigenic combinations may work best. Mechanism Subunit vaccines contain fragments of the pathogen, such as protein or polysaccharide, whose combinations are carefully selected to i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin E
Immunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig) " isotype") that has been found only in mammals. IgE is synthesised by plasma cells. Monomers of IgE consist of two heavy chains (ε chain) and two light chains, with the ε chain containing four Ig-like constant domains (Cε1–Cε4). IgE is thought to be an important part of the immune response against infection by certain parasitic worms, including ''Schistosoma mansoni'', ''Trichinella spiralis'', and ''Fasciola hepatica''. IgE is also utilized during immune defense against certain protozoan parasites such as ''Plasmodium falciparum''. IgE may have evolved as a defense to protect against venoms. IgE also has an essential role in type I hypersensitivity, which manifests in various allergic diseases, such as allergic asthma, most types of sinusitis, allergic rhinitis, food allergies, and specific types of chronic urticaria and atopic dermatitis. IgE also plays a pivotal role in responses to allergens, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Growth Factor Receptor
A growth factor receptor is a receptor that binds to a growth factor. Growth factor receptors are the first stop in cells where the signaling cascade for cell differentiation and proliferation begins. Growth factors, which are ligands that bind to the receptor are the initial step to activating the growth factor receptors and tells the cell to grow and/or divide. These receptors may use the JAK/STAT, MAP kinase, and PI3 kinase pathways. A majority of growth factor receptors consists of receptor tyrosine kinases (RTKs). There are 3 dominant receptor types that are exclusive to research : the epidermal growth factor receptor, the neurotrophin receptor, and the insulin receptors. All growth factor receptors are membrane bound and composed of 3 general protein domains: extracellular, transmembrane, and cytoplasmic. The extracellular domain region is where a ligand may bind, usually with very high specificity. In RTKs, the binding of a ligand to the extracellular ligand binding sit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rindopepimut
Rindopepimut (CDX-110) is an injectable peptide cancer vaccine which targets a mutant protein called EGFRvIII present in about 25% to 30% of glioblastoma cases. The vaccine consists of the EGFRv3-specific peptide (a 13-amino acid mutant vIII epitope) conjugated to the non-specific immunomodulator keyhole limpet hemocyanin (KLH). The US FDA granted it Breakthrough Therapy designation for glioblastoma in Feb 2015 meaning that it might be able to get approval sooner if it is effective. __TOC__ Clinical trials Glioblastoma The phase II ACT III study reported encouraging results in June 2015. The ReACT clinical trial for glioblastoma reported encouraging results in 2015. In March 2016 the phase III ACT IV trial was terminated because it did not increase overall survival Survival rate is a part of survival analysis. It is the proportion of people in a study or treatment group still alive at a given period of time after diagnosis. It is a method of describing prognosis in certain ... [...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 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
In Vitro
''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology and its subdisciplines are traditionally done in labware such as test tubes, flasks, Petri dishes, and microtiter plates. Studies conducted using components of an organism that have been isolated from their usual biological surroundings permit a more detailed or more convenient analysis than can be done with whole organisms; however, results obtained from ''in vitro'' experiments may not fully or accurately predict the effects on a whole organism. In contrast to ''in vitro'' experiments, ''in vivo'' studies are those conducted in living organisms, including humans, and whole plants. Definition ''In vitro'' ( la, in glass; often not italicized in English usage) studies are conducted using components of an organism that have been isolated fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanoma
Melanoma, also redundantly known as malignant melanoma, is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. Melanomas typically occur in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In women, they most commonly occur on the legs, while in men, they most commonly occur on the back. About 25% of melanomas develop from moles. Changes in a mole that can indicate melanoma include an increase in size, irregular edges, change in color, itchiness, or skin breakdown. The primary cause of melanoma is ultraviolet light (UV) exposure in those with low levels of the skin pigment melanin. The UV light may be from the sun or other sources, such as tanning devices. Those with many moles, a history of affected family members, and poor immune function are at greater risk. A number of rare genetic conditions, such as xeroderma pigmentosum, also increase the risk. Diagnosis is by biopsy and analysis of any skin lesion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunologic Adjuvant
In immunology, an adjuvant is a substance that increases or modulates the immune response to a vaccine. The word "adjuvant" comes from the Latin word ''adiuvare'', meaning to help or aid. "An immunologic adjuvant is defined as any substance that acts to accelerate, prolong, or enhance antigen-specific immune responses when used in combination with specific vaccine antigens." In the early days of vaccine manufacture, significant variations in the efficacy of different batches of the same vaccine were correctly assumed to be caused by contamination of the reaction vessels. However, it was soon found that more scrupulous cleaning actually seemed to ''reduce'' the effectiveness of the vaccines, and some contaminants actually enhanced the immune response. There are many known adjuvants in widespread use, including aluminium salts, oils and virosomes. Overview Adjuvants in immunology are often used to modify or augment the effects of a vaccine by stimulating the immune system to re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Helix
The alpha helix (α-helix) is a common motif in the secondary structure of proteins and is a right hand-helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O group of the amino acid located four residues earlier along the protein sequence. The alpha helix is also called a classic Pauling–Corey–Branson α-helix. The name 3.613-helix is also used for this type of helix, denoting the average number of residues per helical turn, with 13 atoms being involved in the ring formed by the hydrogen bond. Among types of local structure in proteins, the α-helix is the most extreme and the most predictable from sequence, as well as the most prevalent. Discovery In the early 1930s, William Astbury showed that there were drastic changes in the X-ray fiber diffraction of moist wool or hair fibers upon significant stretching. The data suggested that the unstretched fibers had a coiled molecular structure with a characteristic repeat of ≈. Astb ... [...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 cells and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
