High Quality Antibodies from ARP
Antibodies are glycoproteins belonging to the immunoglobulin superfamily. They are created in response to foreign substances (antigens) being introduced into the body. Their purpose is to protect the body against disease and infection. There are many different types of antibodies that are segmented into five different antibody isotypes in mammals. They perform different roles and help direct the appropriate immune response for each different type of foreign object they encounter. Though the general structure of all antibodies is very similar, a small region at the tip of the protein is extremely variable, allowing millions of antibodies with slightly different tip structures, or antigen binding sites, to exist. This region is known as the hypervariable region. Each of these variants can bind to a different antigen. This variability allows the immune system to recognize an equally wide variety of antigens. Antibodies can be purified and used in many applications. They can be used to:
- Identify and locate intracellular and extracellular proteins
- Examine protein expression in tissue sections
- Locate proteins within cells with the assistance of a microscope
- Used in immunoprecipitation to separate proteins and anything bound to them (co-immunoprecipitation) from other molecules in a cell lysate
Antibody Supplier of Monoclonal and Polyclonal Antibodies
ARP offers both monoclonal antibodies and polyclonal antibodies to research customers. For 20 years, we’ve been offering the scientific community the highest quality, pure antibodies.
Are made of one type of antibody that can detect one type of determinant of an antibody. They are always identical and homogeneous, which make them ideal for testing that requires conditions to be constant.
These contain numerous antibodies that bind to one antigen. They are typically able to recognize various determinants of an antigen. However, these antibodies are prone to variability making them useful for immunoprecipitation.
How Antibodies are Produced
Specific antibodies are produced by injecting an antigen into a mammal, such as a mouse, rat, rabbit, goat, sheep, or horse. Blood isolated from these animals contains polyclonal antibodies — multiple antibodies that bind to the same antigen — in the serum, which can now be called antiserum. Antigens are also injected into chickens for generation of polyclonal antibodies in egg yolk. To obtain an antibody that is specific for a single epitope of an antigen, antibody-secreting lymphocytes are isolated from the animal and immortalized by fusing them with a cancer cell line. The fused cells are called hybridomas, and will continually grow and secrete antibody in culture. Single hybridoma cells are isolated by dilution cloning to generate cell clones that all produce the same antibody, known as monoclonal antibodies. Polyclonal and monoclonal antibodies are often purified using Protein A/G or antigen-affinity chromatography.
Antibodies in Research
Purified antibodies are used in many applications. They are most commonly used to identify and locate intracellular and extracellular proteins. Antibodies are used in flow cytometry to differentiate cell types by the proteins they express. Different types of cell express different combinations of cluster of differentiation molecules on their surface and produce different intracellular and secretable proteins. They are also used in immunoprecipitation to separate proteins and anything bound to them (co-immunoprecipitation) from other molecules in a cell lysate, in Western blot analysis, to identify proteins separated by electrophoresis, and in immunohistochemistry or immunofluorescence to examine protein expression in tissue sections or to locate proteins within cells with the assistance of a microscope. Proteins can also be detected and quantified with antibodies, using ELISA and ELISPOT techniques.