|
HEK293
Human embryonic kidney 293 cells, also often referred to as HEK 293, HEK-293, 293 cells, are an immortalised cell line derived from HEK cells isolated from a female fetus in the 1970s. The HEK 293 cell line has been widely used in research for decades due to its reliable and fast growth and propensity for transfection. The cell line is used by the biotechnology industry to produce therapeutic proteins and viruses for gene therapy as well as safety testing for a vast array of chemicals. History HEK 293 cells were generated in 1973 by transfection of cultures of normal human embryonic kidney cells with sheared adenovirus 5 DNA in Alex van der Eb's laboratory in Leiden, the Netherlands. The cells were obtained from a single, aborted or miscarried fetus, the precise origin of which is unclear. The cells were cultured by van der Eb; the transfection with adenoviral DNA was performed by Frank Graham, a post-doc in van der Eb's lab. They were published in 1977 after Graham left Leid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lex Van Der Eb
Alex Jan "Lex" van der Eb (born 16 January 1934) is a Dutch molecular biologist and virologist. He was a professor of fundamental tumor virology and later molecular carcinogenesis at Leiden University from 1979 to 2000. He has performed research in adenoviruses and was fundamental in the creation of the technique of calcium phosphate transfection and the founding of the HEK 293 and PER.C6 cell lines. Life Van der Eb was born on 16 January 1934 in Bandung, Dutch East Indies. He studied biology at Leiden University and afterwards attended Delft University of Technology for a further year to specialize in microbiology. Van der Eb had to fulfill his military service upon graduation and asked the head of military health services to be employed in one of the military laboratories. In 1962 he was sent to work as a biologist on poxviruses in the virology department of Leiden University. At Leiden he met professor J.A. Cohen of the Medical-Biological Laboratory of the Netherlands Organis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immortalised Cell Line
An immortalised cell line is a population of cells from a multicellular organism that would normally not proliferate indefinitely but, due to mutation, have evaded normal cellular senescence and instead can keep undergoing division. The cells can therefore be grown for prolonged periods ''in vitro''. The mutations required for immortality can occur naturally or be intentionally induced for experimental purposes. Immortal cell lines are a very important tool for research into the biochemistry and cell biology of multicellular organisms. Immortalised cell lines have also found uses in biotechnology. An immortalised cell line should not be confused with stem cells, which can also divide indefinitely, but form a normal part of the development of a multicellular organism. Relation to natural biology and pathology There are various immortal cell lines. Some of them are normal cell lines (e.g. derived from stem cells). Other immortalised cell lines are the ''in vitro'' equivalent of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuron
A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural network in the nervous system. They are located in the nervous system and help to receive and conduct impulses. Neurons communicate with other cells via synapses, which are specialized connections that commonly use minute amounts of chemical neurotransmitters to pass the electric signal from the presynaptic neuron to the target cell through the synaptic gap. Neurons are the main components of nervous tissue in all Animalia, animals except sponges and placozoans. Plants and fungi do not have nerve cells. Molecular evidence suggests that the ability to generate electric signals first appeared in evolution some 700 to 800 million years ago, during the Tonian period. Predecessors of neurons were the peptidergic secretory cells. They eventually ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neomycin
Neomycin, also known as framycetin, is an aminoglycoside antibiotic that displays bactericidal activity against Gram-negative aerobic bacilli and some anaerobic bacilli where resistance has not yet arisen. It is generally not effective against Gram-positive bacilli and anaerobic Gram-negative bacilli. Neomycin comes in oral and topical formulations, including creams, ointments, and eyedrops. Neomycin belongs to the aminoglycoside class of antibiotics that contain two or more amino sugars connected by glycosidic bonds. Neomycin was discovered in 1949 by microbiologist Selman Waksman and his student Hubert Lechevalier at Rutgers University. Neomycin received approval for medical use in 1952. Rutgers University was granted the patent for neomycin in 1957. Discovery Neomycin was discovered in 1949 by the microbiologist Selman Waksman and his student Hubert Lechevalier at Rutgers University. It is produced naturally by the bacterium '' Streptomyces fradiae''. Synthesis req ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BOSC23
BOSC 23 is a human kidney cell line developed by Warren Pear in David Baltimore's lab that was derived from the 293T cell line. The main use of BOSC 23 is the production of recombinant retroviruses; it stably expresses Moloney murine leukemia virus proteins and when transiently transfected with recombinant retroviral vector DNA, produces high titers of infectious retroviral particles. The cell line does not produce detectable replication-competent virus, an important safety feature. BOSC 23 carries neomycin/G418 resistance derived from its parental line 293T, and also hygromycin and mycophenolic acid (gpt) resistance. It should be maintained under gpt selection. This cell line is a model for cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ... research, with emphasis on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SV40 Large T Antigen
SV40 large T antigen ( Simian Vacuolating Virus 40 TAg) is a hexamer protein that is a dominant-acting oncoprotein derived from the polyomavirus SV40. TAg is capable of inducing malignant transformation of a variety of cell types. The transforming activity of TAg is due in large part to its perturbation of the retinoblastoma (pRb) and p53 tumor suppressor proteins. In addition, TAg binds to several other cellular factors, including the transcriptional co-activators p300 and CBP, which may contribute to its transformation function. Similar proteins from related viruses are known as large tumor antigen in general. TAg is a product of an early gene transcribed during viral infection by SV40, and is involved in viral genome replication and regulation of host cell cycle. SV40 is a double-stranded, circular DNA virus belonging to the Polyomaviridae (earlier Papovavirus) family, Orthopolyomavirus genus. Polyomaviruses infect a wide variety of vertebrates and cause solid tumours ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transfection
Transfection is the process of deliberately introducing naked or purified nucleic acids into eukaryotic cells. It may also refer to other methods and cell types, although other terms are often preferred: " transformation" is typically used to describe non-viral DNA transfer in bacteria and non-animal eukaryotic cells, including plant cells. In animal cells, transfection is the preferred term, as the term "transformation" is also used to refer to a cell's progression to a cancerous state (carcinogenesis). Transduction is often used to describe virus-mediated gene transfer into prokaryotic cells. The word ''transfection'' is a portmanteau of the prefix ''trans-'' and the word "infection." Genetic material (such as supercoiled plasmid DNA or siRNA constructs), may be transfected. Transfection of animal cells typically involves opening transient pores or "holes" in the cell membrane to allow the uptake of material. Transfection can be carried out using calcium phosphate (i.e. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y Chromosome
The Y chromosome is one of two sex chromosomes in therian mammals and other organisms. Along with the X chromosome, it is part of the XY sex-determination system, in which the Y is the sex-determining chromosome because the presence of the Y chromosome causes offspring produced in sexual reproduction to be of male sex. In mammals, the Y chromosome contains the SRY gene, which triggers development of male gonads. The Y chromosome is passed only from male parents to male offspring. Overview Discovery The Y chromosome was identified as a sex-determining chromosome by Nettie Stevens at Bryn Mawr College in 1905 during a study of the mealworm ''Tenebrio molitor''. Edmund Beecher Wilson independently discovered the same mechanisms the same year, working with Hemiptera. Stevens proposed that chromosomes always existed in pairs and that the smaller chromosome (now labelled "Y") was the pair of the X chromosome discovered in 1890 by Hermann Henking. She realized that th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ECACC
The European Collection of Authenticated Cell Cultures (ECACC) houses and supplies cell lines. It is part of the Culture Collections of Public Health England. The collection is held in Porton Down Porton Down is a science and defence technology campus in Wiltshire, England, just north-east of the village of Porton, near Salisbury. It is home to two British government facilities: a site of the Ministry of Defence's Defence Science and .... ECACC, which was established in 1984, consists of a team with specialist knowledge which supply authenticated cell lines, induced Pluripotent stem cells (iPSCs) and nucleic acids to provide stock for the research community. ECACC is one of the first collections of authenticated cell cultures worldwide and now holds cell lines from 45 species including 50 tissue types, 300 HLA types, over 800 genetic disorders and roughly 450 monoclonal antibodies. ECACC products are trademarked with Public Health England and the trademark cannot be used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 22 (human)
Chromosome 22 is one of the 23 pairs of chromosomes in human cells. Humans normally have two copies of chromosome 22 in each cell. Chromosome 22 is the second smallest human chromosome, spanning about 51 million DNA base pairs and representing between 1.5 and 2% of the total DNA in cells. In 1999, researchers working on the Human Genome Project announced they had determined the sequence of base pairs that make up this chromosome. Chromosome 22 was the first human chromosome to be fully sequenced. Human chromosomes are numbered by their apparent size in the karyotype, with chromosome 1 being the largest and chromosome 22 having originally been identified as the smallest. However, genome sequencing has revealed that chromosome 21 is actually smaller than chromosome 22. Genes Number of genes The following are some of the gene count estimates of human chromosome 22. Because researchers use different approaches to genome annotation, their predictions of the number of genes on ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 17 (human)
Chromosome 17 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 17 spans more than 84 million base pairs (the building material of DNA) and represents between 2.5 and 3% of the total DNA in cells. Chromosome 17 contains the Homeobox B gene cluster. Genes Number of genes The following are some of the gene count estimates of human chromosome 17. Because researchers use different approaches to genome annotation their predictions of the number of genes on each chromosome varies (for technical details, see gene prediction). The most conservative estimate, from CCDS, represents a lower bound on the total number of human protein-coding genes. Gene list The following is a partial list of genes on human chromosome 17. For complete list, see the link in the infobox on the right. The following are some of the genes and their corresponding Cytogenetic location on chromosome 17: p-arm q-arm Diseases and disord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X Chromosomes
The X chromosome is one of the two sex chromosomes in many organisms, including mammals, and is found in both males and females. It is a part of the XY sex-determination system and XO sex-determination system. The X chromosome was named for its unique properties by early researchers, which resulted in the naming of its counterpart Y chromosome, for the next letter in the alphabet, following its subsequent discovery. Discovery It was first noted that the X chromosome was special in 1890 by Hermann Henking in Leipzig. Henking was studying the testicles of '' Pyrrhocoris'' and noticed that one chromosome did not take part in meiosis. Chromosomes are so named because of their ability to take up staining (''chroma'' in Greek means ''color''). Although the X chromosome could be stained just as well as the others, Henking was unsure whether it was a different class of the object and consequently named it ''X element'', which later became X chromosome after it was established that it wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
