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    Displaying items by tag: antibody
    Monday, 27 October 2014 13:24

    Rabbit polyclonal antibody

    Code

    04-rb-anti-ERα17p-500                         04-rb-anti-ERα17p-200

    Size

    500 µL                                                   200 µL

    Price

    385 Euros                                              175 Euros

    Product Name

    ERα17p rabbit polyclonal antibody

    Product type

    Primary antibodies

    Immunogen

    ERα17p is a synthetic peptide corresponding to a regulatory motif located within the autonomous AF-2a region of the estrogen receptor α (ERα)

    Tested applications

    ELISA, WESTERN BLOT

    Application notes

    Recommended dilutions

    ELISA: serum: 1/20-1/1000        antigen: 2 µg/mL-5 µg/mL

    WESTERN BLOTserum: 1/100-1/2000            antigen: 10-8-10-5M

    Raised in

    Rabbit

    Clonality

    Polyclonal

    Storage buffer

    0.1% azide

    Form

    Liquid

    storage instructions

    Store at +4°C short term (1 week). Aliquot and store at -20°C or -80°C. Avoid repeated freeze / thaw cycles.

    Expiration

    31/12/2015

    Published in Promos
    Friday, 08 November 2013 16:58

    New Melanoma Panels

    Each antibody for melanoma is available as a 2ml, 7ml, or 25ml ready-to-use antibody as well as in concentrated form.  Perhaps the most exciting antibody is our pan Melanoma which contains four different clones in order to make the cocktail more sensitive and also more valuable as a diagnostic tool for metastatic melanoma.

    Product List:

    Melanoma; Pan (Concentrate)

    Species: Mouse
    Clones: MART-1; Clone M2-7C10, MART-1; Clone M2-9E3, Tyrosinase; Clone T311, Melanoma: HMB45.
    Isotype: Mouse IgG1
    Species Reactivity: Human.
    Positive Control: Human Melanoma
    Specificity: HMB45 has been shown to be a very specific marker for melanomas.
     

    Melanoma; Pan (Ready-To-Use)

    Species: Mouse
    Clones: MART-1; Clone M2-7C10, MART-1; Clone M2-9E3, Tyrosinase; Clone T311, Melanoma: HMB45.
    Isotype: Mouse IgG1
    Species Reactivity: Human.
    Positive Control: Human Melanoma
    Specificity: HMB45 has been shown to be a very specific marker for melanomas.

    MART-1; Clones M2-7C10 & M2-9E3 (Ready-To-Use)

    Species: Mouse
    Clones: M2-7C10 & M2-9E3
    Isotype: Mouse IgG2b, kappa
    Species Reactivity: Human.
    Positive Control: Human Melanoma.
    Specificity: MART-1 has been shown to be a very specific marker for melanomas.

    MART-1; Clones M2-7C10 & M2-9E3 (Ready-To-Use)

    Species: Mouse
    Clones: M2-7C10 & M2-9E3
    Isotype: Mouse IgG2b, kappa
    Species Reactivity: Human.
    Positive Control: Human Melanoma.
    Specificity: MART-1 has been shown to be a very specific marker for melanomas.

    Tyrosinase; Clone T311 (Concentrate)

    Species: Mouse
    Clone: T311
    Isotype: Mouse IgG1
    Species Reactivity: Human.
    Positive Control: Human Melanoma
    Specificity: Tyrosinase has been shown to be a very specific marker for melanomas, not cross reacting with other tumors or normal tissues tested.

    Tyrosinase; Clone T311 (Ready-To-Use)

    Species: Mouse
    Clone: T311
    Isotype: Mouse IgG1
    Species Reactivity: Human.
    Positive Control: Human Melanoma
    Specificity: Tyrosinase has been shown to be a very specific marker for melanomas. Cross reactivity with other tumors or normal tissues tested has not been reported.

    MART-1; Clone M2-9E2 (Concentrate)

    Species: Mouse
    Clone: M2-9E2
    Isotype: Mouse IgG2b, Kappa
    Species Reactivity: Human, Mouse, Rat.
    Positive Control: Metastatic melanoma in lymph nodes.
    Specificity: The clone M2-9E2 MART-1 antibody labels melanomas and other tumors showing melanocyte differentiation.

    MART-1; Clone M2-9E2 (Ready-To-Use)

    Species: Mouse
    Clone: M2-9E2
    Isotype: Mouse IgG2b, Kappa
    Species Reactivity: Human, Mouse, Rat.
    Positive Control: Metastatic melanoma in lymph nodes.
    Specificity: The clone M2-9E2 MART-1 antibody labels melanomas and other tumors showing melanocyte differentiation.

    MART-1; Clone M2-7C10 (Concentrate)

    Species: Mouse
    Clone: M2-7C10
    Isotype: Mouse IgG2b, Kappa
    Species Reactivity: Human. Clone M2-7C10 does not react with mouse or rat.
    Positive Control: Metastatic melanoma in lymph nodes.
    Specificity: The clone M2-7C10 MART-1 antibody labels melanomas and other tumors showing melanocyte differentiation.

    MART-1; Clone M2-7C10 (Ready-To-Use)

    Species: Mouse
    Clone: M2-7C10
    Isotype: Mouse IgG2b, Kappa
    Species Reactivity: Human. Clone M2-7C10 does not react with mouse or rat.
    Positive Control: Metastatic melanoma in lymph nodes.
    Specificity: The clone M2-7C10 MART-1 antibody labels melanomas and other tumors showing melanocyte differentiation.

    S-100, Clone 4C4.9

      Species: Mouse Monoclonal
    Clone: 4C4.9
    Isotype: IgG2a
    MW: 21-24 kD
    Species Reactivity: Human, Cow, Mouse
    Positive Control: Melanoma or Schwannoma.

    Specificity: Recognizes proteins of 21-24kDa, identified as the A and B subunits of S100 protein. S100 belongs to the family of calcium binding proteins such as calmodulin and troponin C. S100A is composed of an alpha and beta chain whereas S100B is composed of two beta chains. Antibody to S100 stains Schwannomas, ependymomas, astrogliomas, almost all benign and malignant melanomas and their metastases. S100 protein is also expressed in the antigen presenting cells such as the Langerhans cells in skin and interdigitating reticulum cells in the paracortex of lymph nodes. S100 protein is highly soluble and may be eluted from frozen tissue during staining.

    Melanoma; Clone HMB45 (Concentrate)

      Species: Mouse
    Clone: HMB45
    Isotype: Mouse IgG1/ Kappa
    Species Reactivity: Human
    Positive Control: Human Melanoma
    Specificity: HMB45 has been shown to be a very specific marker for melanomas.
     

    Melanoma; Clone HMB45

      Species: Mouse Monoclonal
    Clone: HMB45
    Isotype: IgG1
    Species Reactivity: Human. Does not react with dog and rat.
    Positive Control: Melanoma

    Specificity: By immunohistochemistry, it specifically recognizes a protein in melanocytes and melanomas. Biochemical nature of its antigen is yet not fully characterized. This antibody reacts with junctional and blue nevus cells and variably with fetal and neonatal melanocytes. Intradermal nevi, normal adult melanocytes, and non-melanocytic cells are negative. It does not stain tumor cells of epithelial, lymphoid, glial, or mesenchymal origin.

     

     

    Click here for Prices!

    Published in Promos

    Experts in the field of engineering, chemical compounds from MIT (Massachusetts Institute of Technology, MIT, USA) showed that the matrix consisting of billions of nanoscale sensors have unique properties that can enhance the safety and efficiency of various drugs, particularly drugs, based on antibodies.

    With these sensors, the scientists were able to characterize the different types of interactions of drugs based on antibodies, which in the long run will help in the development of effective treatments for cancer and other diseases. The sensors can be used to assess the structure of antibody molecules and determining their content of sugar chains that prevent their functioning.

    "Pharmacological method can help companies identify the reason for a certain technology of preparation of medicines work better than others, which will increase the efficiency of production", - says Michael Strano (Michael Strano), a professor of chemical engineering at MIT, one of the authors of the Nanoscale sensors, recently published in the journal ACS Nano.

    According to Strano, the research team also demonstrated how nanosensor matrix can be used to determine the most productive and preferred cells in a population of genetically modified cells that synthesize drugs.

    Evaluating the effectiveness of drugs

    nano-teratoma-teratoma-service-ipscThe results of previous studies conducted by countries and other scientists have shown that the use of the finest nanoscale sensors, such as carbon nanotubes, is an effective method to determine the chemical compounds present in the solution in small amounts. Carbon nanotubes are 50 thousand times thinner than a human hair. They are able to join the proteins recognize specific Targeted molecule. If the solution contains Targeted molecule fluorescent signal produced by the carbon nanotube varies and it can be detected.

    For the simultaneous determination of a large number of different targets in solution, some scientists are trying to use a large array of nanosensors, in particular, carbon nanotubes or semiconductor nanowires, each of which focuses on a specific targeted molecule. In the new study, Strano and his colleagues studied the unique properties of large sensors that detect the same chemical.

    The first property, scientists detected nanosensors - is that the matrix consisting of equally spaced sensors can measure the force distribution compounds arising in complex proteins such as antibodies.

    Antibodies - the body naturally synthesized molecules that play a key role in the immune response. In recent years, scientists have developed antibodies to treat various diseases, including cancer. The addition of these antibodies to surface proteins of cancer cells stimulates an immune response to the tumor.

    To drugs based on antibodies to be effective, they must be specifically attached to its target. However, the process of antibody production , which is dependent on engineering cells does not always lead to the production of consistently and uniformly acceding parties antibodies.

    Currently, for testing batches of drugs in order to confirm their compliance with the performance standards used by pharmaceutical companies for long time and expensive analytical processes. The new sensor, developed by scientists from MIT, can greatly speed up the process, allowing scientists not only to more effectively monitor and control the process of production of drugs, but also to fine-tune their production. This will result in a more uniform product synthesized.

    Measurements of weak interactions

    Another nice feature of sensors is their ability to measure the weak binding interactions that can also help in the production of drugs based on antibodies.

    Normally, this process of protein glycosylation antibodies surface is covered with long chains of carbohydrates which provide drug efficacy. But sugar chain is extremely difficult to detect, since they interact with weak bonds with other molecules. Organisms that produce antibodies are programmed in such a way as to connect the chain of sugars. However, this process is difficult to control, and it largely depends on the environment surrounding the cells, including the temperature and acidity.

    If an antibody is introduced into the patient will not be glycosylated proteins, they can cause the development of an unwanted immune response or be destroyed by the patient's own cells, making them useless.

    According to Strano, drug companies and scientists who have tried to identify glycosylated proteins by recognizing the hydrocarbon chains, experienced difficulties. "Nanosensor matrix can greatly increase the possibility of determining the rare events of joining molecules. You will be able to measure something that is not able to estimate with a large sensor with the same sensitivity, "- says the country.

    The new method could help scientists determine the optimal conditions for adjusting the degree of glycosylation of proteins that facilitate the production of equally effective drugs.

    The definition of the product obtained

    The third property of nanoscale sensors, studied by scientists - is the ability to detect the synthesis of a molecule of interest. According to Strano, professionals want to be able to identify specific strains of microorganisms that synthesize the necessary medicines. "There are many ways to do this, but none of them is not easy," - says the country.

    The research team from MIT found that culturing the cells on the surface coated with a matrix of nanoscale sensors that can help identify the location of the majority of synthesizing cells. In the new study, the researchers studied the antibodies are synthesized artificially synthesized human embryonic kidney cells. However, established engine also can be individually configured to proteins and other organisms.

    According to Strano, immediately after the detection of the most productive cells, scientists are studying the genes that distinguish these cells from other cells that have a lower efficiency in the production of medicines. As a result, they create a new strain having increased ability to synthesize the desired chemical compounds.

    Scientists have created a prototype of a portable sensor, which they plan to test in the pharmaceutical company Novartis. The study will be funded by Novartis and the National Science Foundation (National Science Foundation, USA).

    Published in News
    Thursday, 29 August 2013 11:23

    Flu antibodies can make disease worse

    antibodySome antibodies to flu viruses may actually make patients sicker, a new study of pigs suggests.

    The finding, published August 28 in Science Translational Medicine, may point to problems with catchall influenza vaccines.

    Pigs vaccinated against a seasonal strain of influenza made antibodies to that strain. Some of the antibodies could also latch on to a different flu virus that caused a pandemic among humans in 2009, report scientists led by Hana Golding of the Food and Drug Administration’s Center for Biologics Evaluation and Research in Bethesda, Md., and Amy Vincent of the Department of Agriculture’s National Animal Disease Center in Ames, Iowa.

    Instead of protecting the pigs against the 2009 pandemic flu, the broad-range antibodies actually helped the virus invade lung cells, causing pneumonia and lung damage.

    Scientists hoping to create a universal flu vaccine need to learn how the pigs’ antibodies and viruses interacted to make the disease worse, James Crowe Jr. of Vanderbilt University writes in a commentary in the same issue of the journal.

    And vaccines aren't the only problem, Crowe says. Natural infections may provoke similar disease-worsening problems.

    Published in News

    Cloned MouseScientists in Japan cloned a mouse from a drop of blood. Moving blood cells taken from the tail of the mouse donor were used to create the clone, said researchers from the center Ricken Bioresources. Some time ago the same scientists have created nearly 600 exact genetic copies of a mouse.

    Mice were cloned from different sources of donor cells, including white blood cells of the lymph nodes, bone marrow and liver. Japanese researchers studied whether the moving blood cells can be used for cloning. Their goal was to find an easy source of donor cells for cloning valuable scientifically types of laboratory mice.

    Scientists led by Atsuo Ogura of Bioresources Rikes center in Tsukuba, blood taken from the tail of a mouse donor, isolated white blood cells and used kernel cloning experiments using the same technique as for the cloning of Dolly the sheep in Edinburgh.

    The process, known as somatic cell nuclear transfer involving transfer of the nucleus from a cell in the adult body as blood cells or skin unfertilized egg, which was removed the nucleus. Scientists, whose research was published in the journal Biology of Reproduction, said that it shows for the first time that mice can be cloned using the nucleus of peripheral blood cells.

    "These cells can be used to clone immediately after isolation, without requiring euthanasia of donor" complemented researchers.

    Published in News

    tobacco-plant-antibodiesSmoking tobacco might be bad for your health, but a genetically altered version of the plant might provide a relatively inexpensive cure for the deadly rabies virus. In a new research report appearing in The FASEB Journal, scientists produced a monoclonal antibody in transgenic tobacco plants that was shown to neutralize the rabies virus. This new antibody works by preventing the virus from attaching to nerve endings around the bite site and keeps the virus from traveling to the brain.

     

    "Rabies continues to kill many thousands of people throughout the developing world every year and can also affect international travelers," said Leonard Both, M.Sc., a researcher involved in the work from the Hotung Molecular Immunology Unit at St. George's, University of London, in the United Kingdom. "An untreated rabies infection is nearly 100 percent fatal and is usually seen as a death sentence. Producing an inexpensive antibody in transgenic plants opens the prospect of adequate rabies prevention for low-income families in developing countries."

     

    To make this advance, Both and colleagues "humanized" the sequences for the antibody so people could tolerate it. Then, the antibody was produced using transgenic tobacco plants as an inexpensive production platform. The antibody was purified from the plant leaves and characterized with regards to its protein and sugar composition. The antibody was also shown to be active in neutralizing a broad panel of rabies viruses, and the exact antibody docking site on the viral envelope was identified using certain chimeric rabies viruses.

     

    "Although treatable by antibodies if caught in time, rabies is bad news," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "This is especially true for people in the developing world where manufacturing costs lead to treatment shortages. Being able to grow safe, humanized antibodies in genetically modified tobacco should reduce costs to make treatments more accessible, and save more lives."

     

     

    Published in News

    In a series of lab experiments designed to unravel the workings of a key enzyme widely considered a possible trigger of rheumatoid arthritis, researchers at Johns Hopkins have found that in the most severe cases of the disease, the immune system makes a unique subset of antibodies that have a disease-promoting role.

    Enzyme-Activating AntibodiesReporting in the journal Science Translational Medicine online May 22, the Johns Hopkins team describes how it found the novel antibodies to peptidylarginine deiminase 4, or PAD4, in blood samples from people with aggressive inflammation and connective tissue damage.

    Researchers say the presence of so-called PAD3/PAD4 cross-reactive autoantibodies could serve as the basis for the first antibody-specific diagnostic test to distinguish those with severe rheumatoid arthritis from those with less aggressive forms of the disease.
    "Identifying early on a subset of patients with severe rheumatoid arthritis could benefit their health, as these patients could start aggressive drug therapy immediately and find the most effective treatment option," says senior study investigator Antony Rosen, M.D. Rosen, director of rheumatology and the Mary Betty Stevens Professor at the Johns Hopkins University School of Medicine, says that a third, or 1 million of the more than 3 million Americans -- mostly women -- estimated to have rheumatoid arthritis have an aggressive form of the disease.
    In the study, the antibodies were present -- in 18 percent of 44 fluid samples from one research collection and in 12 percent of another collection of 194 -- but only in people with severe cases of rheumatoid arthritis. Past research shows that those with the most aggressive disease are less likely to respond to anti-inflammatory treatments with steroids and other drugs.
    An examination of patients' medical records revealed that 80 percent of patients with the antibody saw their disease worsen over the previous year, while only 53 percent without the antibody showed disease progression. In comparing average scores of disease-damaged joints, researchers found that those with the antibody had an average deterioration in joints and bones by a score of 49. Those without the antibody had an average degradation in their score of 7.5, indicating much milder disease.
    In a related finding, the Johns Hopkins team also uncovered how the PAD3/PAD4 cross-reactive auto-antibodies might contribute to more severe, erosive disease in rheumatoid arthritis. The team performed a series of experiments to gauge the antibodies' effects on PAD4 in response to varying cell levels of calcium, on which PAD enzymes depend.
    Lab experiments showed that the antibodies greatly increase PAD4 enzyme function at the low levels of calcium normally present in human cells. Results showed that PAD4 activity was 500 times greater in the presence of antibodies than when they were absent. Tests of the antibody and enzymes' chemical structures later showed that the antibodies bind to PAD4 in the same region as calcium, suggesting to researchers that the antibodies might be substituting for calcium in activating the enzyme.
    According to Rosen, the series of experiments, which took two years to complete, represents the first evidence of an antibody having a direct role in generating the targets of the immune response, or auto-antigens, in rheumatoid arthritis.
    "Our results suggest that drugs inhibiting the PAD4 enzyme may have real benefit in patients with severe rheumatoid arthritis and represent an important field of study for investigating new and alternative treatments," says lead study investigator and biologist Erika Darrah, Ph.D.
    Darrah says the team next plans long-term monitoring of arthritis sufferers to find out when the antibody first appears in the blood, and when intervention may have maximum impact in preventing or stalling disease progression. The team also plans further experiments to see if the antibody is taking control of the chemical pathways normally used by other cell proteins to control PAD4 sensitivity to calcium.
    Funding support for this study was provided by the National Institutes of Health, and corresponding grant number T32-AR048522; the American College of Rheumatology; the Donald B. and Dorothy L. Stabler Foundation; and Sibley Memorial Hospital.
    In addition to Rosen and Darrah, other Johns Hopkins researchers involved in this study were Jon Giles, M.D.; Michelle Ols, Ph.D.; and Felipe Andrade, M.D., Ph.D. Additional research assistance was provided by enzymologist Herbert Bull, Ph.D.

    Published in News

    130422154756-largeCurrent techniques for turning patients' marrow cells into cells of some other desired type are relatively cumbersome, risky and effectively confined to the lab dish. The new finding points to the possibility of simpler and safer techniques. Cell therapies derived from patients' own cells are widely expected to be useful in treating spinal cord injuries, strokes and other conditions throughout the body, with little or no risk of immune rejection.
    "These results highlight the potential of antibodies as versatile manipulators of cellular functions," said Richard A. Lerner, the Lita Annenberg Hazen Professor of Immunochemistry and institute professor in the Department of Cell and Molecular Biology at TSRI, and principal investigator for the new study. "This is a far cry from the way antibodies used to be thought of -- as molecules that were selected simply for binding and not function."
    The researchers discovered the method, reported in the online Early Edition of the Proceedings of the National Academy of Sciences the week of April 22, 2013, while looking for lab-grown antibodies that can activate a growth-stimulating receptor on marrow cells. One antibody turned out to activate the receptor in a way that induces marrow stem cells -- which normally develop into white blood cells -- to become neural progenitor cells, a type of almost-mature brain cell.
    Nature's Toolkit
    Natural antibodies are large, Y-shaped proteins produced by immune cells. Collectively, they are diverse enough to recognize about 100 billion distinct shapes on viruses, bacteria and other targets. Since the 1980s, molecular biologists have known how to produce antibodies in cell cultures in the laboratory. That has allowed them to start using this vast, target-gripping toolkit to make scientific probes, as well as diagnostics and therapies for cancer, arthritis, transplant rejection, viral infections and other diseases.
    In the late 1980s, Lerner and his TSRI colleagues helped invent the first techniques for generating large "libraries" of distinct antibodies and swiftly determining which of these could bind to a desired target. The anti-inflammatory antibody Humira®, now one of the world's top-selling drugs, was discovered with the benefit of this technology.
    Last year, in a study spearheaded by TSRI Research Associate Hongkai Zhang, Lerner's laboratory devised a new antibody-discovery technique -- in which antibodies are produced in mammalian cells along with receptors or other target molecules of interest. The technique enables researchers to determine rapidly not just which antibodies in a library bind to a given receptor, for example, but also which ones activate the receptor and thereby alter cell function.
    Lab Dish in a Cell
    For the new study, Lerner laboratory Research Associate Jia Xie and colleagues modified the new technique so that antibody proteins produced in a given cell are physically anchored to the cell's outer membrane, near its target receptors. "Confining an antibody's activity to the cell in which it is produced effectively allows us to use larger antibody libraries and to screen these antibodies more quickly for a specific activity," said Xie. With the improved technique, scientists can sift through a library of tens of millions of antibodies in a few days.
    In an early test, Xie used the new method to screen for antibodies that could activate the GCSF receptor, a growth-factor receptor found on bone marrow cells and other cell types. GCSF-mimicking drugs were among the first biotech bestsellers because of their ability to stimulate white blood cell growth -- which counteracts the marrow-suppressing side effect of cancer chemotherapy.
    The team soon isolated one antibody type or "clone" that could activate the GCSF receptor and stimulate growth in test cells. The researchers then tested an unanchored, soluble version of this antibody on cultures of bone marrow stem cells from human volunteers. Whereas the GCSF protein, as expected, stimulated such stem cells to proliferate and start maturing towards adult white blood cells, the GCSF-mimicking antibody had a markedly different effect.
    "The cells proliferated, but also started becoming long and thin and attaching to the bottom of the dish," remembered Xie.
    To Lerner, the cells were reminiscent of neural progenitor cells -- which further tests for neural cell markers confirmed they were.
    A New Direction
    Changing cells of marrow lineage into cells of neural lineage -- a direct identity switch termed "transdifferentiation" -- just by activating a single receptor is a noteworthy achievement. Scientists do have methods for turning marrow stem cells into other adult cell types, but these methods typically require a radical and risky deprogramming of marrow cells to an embryonic-like stem-cell state, followed by a complex series of molecular nudges toward a given adult cell rate. Relatively few laboratories have reported direct transdifferentiation techniques.
    "As far as I know, no one has ever achieved transdifferentiation by using a single protein -- a protein that potentially could be used as a therapeutic," said Lerner.
    Current cell-therapy methods typically assume that a patient's cells will be harvested, then reprogrammed and multiplied in a lab dish before being re-introduced into the patient. In principle, according to Lerner, an antibody such as the one they have discovered could be injected directly into the bloodstream of a sick patient. From the bloodstream it would find its way to the marrow, and, for example, convert some marrow stem cells into neural progenitor cells. "Those neural progenitors would infiltrate the brain, find areas of damage and help repair them," he said.
    While the researchers still aren't sure why the new antibody has such an odd effect on the GCSF receptor, they suspect it binds the receptor for longer than the natural GCSF protein can achieve, and this lengthier interaction alters the receptor's signaling pattern. Drug-development researchers are increasingly recognizing that subtle differences in the way a cell-surface receptor is bound and activated can result in very different biological effects. That adds complexity to their task, but in principle expands the scope of what they can achieve. "If you can use the same receptor in different ways, then the potential of the genome is bigger," said Lerner.
    In addition to Lerner and Xie, contributors to the study, "Autocrine Signaling Based Selection of Combinatorial Antibodies That Transdifferentiate Human Stem Cells," were Hongkai Zhang of the Lerner Laboratory, and Kyungmoo Yea of The Scripps Korea Antibody Institute, Chuncheon-si, Korea.
    Funding for the study was provided by The Scripps Korea Antibody Institute and Hongye Innovative Antibody Technologies (HIAT).

    Published in News

    Red squirrel gentaur antibodiesAs parents, we set our children up for life’s challenges by feeding them, caring for their health, and sending them to school. Many animals also provide for their young, and some do it in inadvertent and surprising ways. Take the red squirrel. The first year of this cute creature’s life is marked by intense competition and imminent death. Its goal is simple: get a territory before winter sets in, or face death by starvation. That goal becomes tougher if there are lots of other competitors around, but a mother squirrel has ways of preparing her pups for these trials. If she hears the sounds of crowded forest, stress hormones surge through her body and begin affecting her pups even before they are born. When they finally pop into the world, they start growing faster. The hormones are a chemical message from mum: Live fast, so you don’t die young.

    Red squirrels have a diverse diet, but the seeds of the white spruce are among the most important items on their menu. These trees are “mast seeders” meaning that they all produce tons of seeds every 2 to 6 years and very few seeds in others. In the bonanza years, the squirrels have plenty of spruce seeds to bury in the autumn and snack on through the harsh winter. This means that a bumper autumn for spruce is always followed by a crowded spring for squirrels. That leads to conflict. Red squirrels defend large areas surrounding a central store of spruce cones. They’ll fight for this real estate, because if the youngsters don’t establish a territory before winter sets in, they’ll find themselves bereft of buried grains, and almost certainly die. A team of Canadian scientists has been studying the fates of red squirrels in the Yukon, Canada for the last 22 years. Back in 2006, they showed that the squirrels can actually anticipate gluts of spruce seeds, and produce more young in anticipation. Now, the same team have found that females can also adjust how quickly their young grow up depending on how much competition they will face.

    The team, led by Ben Dantzer, now at the University of Cambridge, found that in competitive years following a spruce bonanza, the fastest-growing squirrels fare best and are more likely to survive their first winter. In normal years, these fast-growers have no advantage. This explains why the mothers don’t always give birth to fast-growing young. It comes at a price—squirrels tend to have shorter lifespans if they are born in crowded years, so their early spurt seems to cost them later on in life. It’s a cost that’s only worth paying if there’s some advantage to be gained. To test this link between density and growth, Dantzer’s team carried out a wonderfully simple but beautiful experiment where they simulated the sounds of a crowd. They recorded the loud “rattles” that squirrels make to defend their territories, and played them back to the creatures at two levels—one representing six times more squirrels than the other. If the females heard what sounded like squirrel-infested woods, they gave birth to pups that grew much faster.

    How? The answer lies in the mothers’ hormones. The more crowded an area is, the higher the levels of cortisol - a stress hormone - in the squirrels’ bodies. Indeed, if Dantzer’s team created more crowded forests - either genuinely so by feeding the squirrels and boosting their numbers, or dishonestly so by playing the rattle recordings - the females’ cortisol levels went up. Mums with higher cortisol levels gave birth to pups that grew faster. This wasn’t just a correlation. The team also injected some females with extra cortisol, and saw that their offspring grew up 41 percent faster.

    Why? This part of the story is less clear. We know from other studies that and early dose of stress hormones can steer the development of young animals, affecting their ability to learn or handle stressful situations. Think of the hormones as an fortune-telling system, plugged into the mother’s senses. It provides the young squirrel with omens of the conditions it will face in the outside world, and prepares its brain and body to deal with those challenges.

     

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    cellsThe biggest breakthrough in understanding the genetics of cancer before. So Iyls Ross, professor of cancer genetics at the Institute of Cancer Research in London, described the results of an international effort of more than 1,000 scientists, presented in late Wednesday.

    Their study - the largest ever study of "faults" of DNA that promote the development of cancer - revealed a series of genetic markers with which can identify people most likely to develop these conditions. In this case for three of the most encountered its forms - prostate, breast and ovarian.

    According to London's "Guardian" doctors have said that they can in five years with a simple saliva test based markers make for each risk profile and create a foundation for individual monitoring. For people with an increased risk of developing cancer would go more often reviewing and possibly developing cancer will be detected at an early stage, when there is a much greater chance of prolonging life.

    Test based on genetic markers can identify men who are 50% likely to become ill from prostate cancer. This would not only allow the UK have called for a national program. screening of men, it will stop the practice because of inaccurate blood tests a quarter of people with this diagnosis are treated, there was no need.

    To identify genetic markers for prostate cancer, the researchers compared the DNA data of 25,000 patients with the disease with the same number of healthy men. So were discovered 23 new "defect" in the DNA, increasing the risk of disease, 16 were identified as "culprits" to reach the most aggressive form. In practice, few men wear markers for prostate cancer, but 1% of them have DNA "defects" that increase the risk of developing it 5 times.

    The same procedure has found 49 new DNA "defect" associated with the risk of developing breast cancer.

    The third part of the project included the 130 institutes worldwide to compare DNA profiles of women with ovarian cancer with this healthy. This established eight new sections of DNA associated with increased risk of disease.

    Professor Iyls believe that a simple test in the GP's office soon enough every patient to have a personal account of the risk of these diseases. Physicians can improve performance by adding factors of lifestyle specific person - the risk of breast cancer, for example, alcohol increases and decreases from birth and breastfeeding.

    The big problem started after that - experts disagree on what age should these tests, complement it with ultrasound, magnetic rezonas and biopsies and what kind therapy to apply.

    The result of the research was published in Nature Genetics and several other scientific journals.

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