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1. Synopsis I'd like to preface this by saying don't randomly use medicines without a doctor's advice. It's fairly unlikely antivenom would cause you any harm but in some cases, antivenom could be dangerous and even lethal. You have to consider possible allergic reactions and the route of administration. In any case, it would be a stupid idea to blithely ...


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Usually an antibody test against HIV is positive three month after the infection. Before this time a test can only be done with molecular biology methods as PCR. However, it is possible, that patients which have definitely been tested in an early phase using molecular biology methods and which afterwards receive a antiretroviral therapy (ART) that these ...


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The key feature of type O blood as "universal donor" is that the incoming red blood cells have neither A nor B antigens and so the resident antibodies (anti-A , anti-B) will not react with them. Since transfusions are carried out with packed red blood cells the plasma antibodies of the donor don't matter - they will not be introduced into the recipient.


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Maybe WB is easier for them to test? In general, however, my recommendation is to check if they provide refs to paper using those antibodies and look at the images on the paper. Be careful putting your trust in the supplier's pictures, I have seen obviously photoshopped images on commercial websites. Also always double-check the referenced papers, as ...


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No, they are of course not there to cause allergies. It is thought (although not directly proven in human) that IgE is important to fight parasites and worms. They bind to antigens from the parasites, which leads to the secretion of histamines. This causes a local immune reaction (which also is a problem in allergies) which is helpful to fight the parasites. ...


6

Making antibodies is mostly nothing you do with transgenic microorganisms. To make an antibody you first have to immunize an animal with the correct antigen. This includes have an animal facility where you can keep animals under clean conditions. If you are looking for polyclonal antibodies (meaning a whole bunch of different antibodies with different ...


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It is! Here is an amazing review from 2011 that literally has all the answers. I'm not kidding, all of them. I would marry this review if I could.1 It also includes information on other animals. The main takeaway is that IgA from milk is not readily absorbed by the infant body. Secreted IgA is mainly to provide a protective coating for the mucosa while ...


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I worked for a long time at a leading high-quality antibody company, so I'll try and share some of my experiences with you. The process of making a highly specific antibody (I'll focus on monoclonals) has three important parts - antigen design and immunization, cloning and subcloning, and screening/validation. Each part is crucial on its own, and the better ...


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Lets define the nomenclature first: An antigen is a large structure (protein, virus, bacteria and so an) which is recognized by the immune system as foreign. The word antigen derives from the abbreviation ANTIbody GENerator. Exposure of our immune system to an antigen results in an immune response and the generation of many antibodies. An epitope is a small ...


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I found some reports on it (like reference 1) but there is an oddly little amount of publications on this topic. then I found this review in Mucosal Immunology (reference 2, interesting to read) which doubts this activation. It says: Interaction with complement IgA lacks the residues identified in the Fc regions of IgG or IgM that bind to C1q, and ...


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Although transmissible cancer has been found in some species, such as Tasmanian Devils and clams, it is quite rare in most species. Certain viral and bacterial agents that cause cancer, however, can be transmitted. One example is HPV, which can cause cervical cancer


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In T-dependent antigen recognition, the B cell can switch the isotype by first altering the heavy chain gene. This is driven by Tfh cells. The specific cytokine stimulating the class switch determines the isotype of the heavy chain to be synthesized. For your example, interleukin 4 (IL-4) drives the class switch to IgE. You also need a costimulatory signal ...


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Okay, you have a few questions building on top of each other (rephrased the questions for clarity): How do scientists discover a new antigen? There are multiple ways to this, which are applied for different purposes. In order to discover a natural antigen, which is recognised by an antibody normally produced by the immune system, one would first have ...


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Immunopanning is essentially an immunoprecipitation (IP) of cells using an antibody immobilized to a solid surface, like a cell culture plate. Conventionally, an IP is performed using small agarose or magnetic beads (~50 to 150μm in size) conjugated to an antibody or Protein A/G, and can pull down individual proteins, protein complexes, and/or nucleic acid ...


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It happens, but it is very rare. Anti-A and Anti-B antibodies are IgM type. They do no cross the placenta. Sometimes IgG can be produced and lead to the hemolytic disease of the newborn. Anti-D antibodies are IgG type and can pass through the placenta.


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Most IgGs should be fine when stored in the freezer. Freezing at -20 or -80 in small aliquots is the optimal storage condition. Ali-quoting minimizes damage due to freezing and thawing, as well as contamination introduced by pipetting from a single vial multiple times. Aliquots are to be frozen and thawed once, with any remainder kept at 4 degrees ...


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There is such a thing as memory plasma cells, discovered only relatively recently. Here is a review from 2010 discussing them, here is another review from 2012, and here is a pre-publication manuscript of an upcoming review in Leukemia (I apologize if any are behind paywalls, let me know if you can't access any of them).


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Molecular context is important here. E.coli in your colon is OK with the body, it is taken up by phagocytes as part of normal "surveillance". Your immune system will learn and gain "tolerence" to these mutualistic bacteria as long as they are in the correct environment. If that same E.coli is a pathogenic strain or finds a way into the blood stream (sepsis),...


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The root of the problem in this case are not the antibodies but the antibody producing cells (APC). They are capable of producing vast amounts of antibody, so I doubt that this approach would be successful. The problem with targeting these APCs is, that you have to know exactly which are the ones which cause the problem, if you want to target them ...


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Within an organism, antibodies which bind to other antibodies in the body would be eliminated during clonal selection. They are not made by the body after that period, which is in the first few months of life. Such antibodies would have to be introduced from the outside. Many have been designed or engineered for biotech and as therapeutics.


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Antibodies are simply proteins and like any other protein have a relatively short "life", so after clearing out an infection, they are not retained for long (most of them anyway). What the body keeps is memory cells which can produce a much more rapid response if they come in contact with the same pathogen again. You could see it as a selective process: the ...


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When the radial immunodiffusion method is used to measure antigen concentrations in samples, a plate or slide is set up using agarose containing an antibody or antiserum. Holes are punched out of the agarose to form wells into which antigen is dispensed. The antigen diffuses out into the agarose and when the antigen/antibody ratio is favourable an ...


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The paratope is the part of an antibody that binds the epitope on the antigen. The CDRs (heavy chain CDRs shown below) are part of the structure of the variable domain, and contain the hypervariable regions that bind to the epitope. From Wikimedia The actual paratope is within the hypervariable regions, which are within the CDRs - the paratope is not ...


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For the generation of Fab-fragments antibodies, (possibly genetically modified) which can be made in large quantities by cells or animals, are used. Antibodies as a whole are not synthesized. The Fab fragment is obtained from antibodies using the enzyme papain, which cleaves the antibody over the disulfide bonds in the hinge region. This results in two Fab ...


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What you can do depends on your proteins: If both proteins (your target protein and the loading control) are seperated far enough, you can detect both of them in the same step by adding both primary antibodies and both secondary ABs into the buffer at the same time. They will bind only to their specific epitope and you will get nice signals. This is ...


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You can compare directly coupled antibodies to the classical indirect primary-secondary systems: Directly coupled antibodies Advantages: quicker workflow as only one antibody is used eliminates the chance of a cross-reacting secondary antibody (possibly less background) possibility to use differently labelled antibodies on the same blot Disadvantages: ...


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You don't specify which temperature of freezer you're talking about. Antibody can be stored at -80 for long time, but needs to avoid freeze and thaw process. Some people store aliquot of antibody in -80. Another way is to dilute antibody in Glycerol, make 50% dilution. You need to mix well, and then store at -20.


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The letter suffix in the name or abbreviation of an immunoglobulin specifies which type of "heavy chain" the immunoglobin contains. The heavy chain is the large polypeptide (amino acid chain) found in the antibody. In mammals there are five different classes or types of heavy chains, and these types are given Greek letters to differentiate them. As ...


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I would like to just add to Nicolai answer. What is an antigen ? First, and Nicolai said this, but I just want to make it clear, an antigen is anything that antibodies bind. That is distinct from and immunogen which is a type of antigen that causes your immune system to produce antibodies. But an antigen does not necessarily have to be an immunogen. ...


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Not only is it possible for multiple antibodies to bind a single antigen, when that happens, it's more likely to trigger a full immune response. Here's a description of the concept from a company that sells antibodies for research. To help understand the quote, you'll need to know that the portion of an antigen that an antibody binds is called an epitope. ...


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