Chimeric antibodies are antibodies that combine parental antibody variable regions and any acceptor constant area. Chimerization does not affect antibody specificity or affinity because of the way antibodies are organized. Chimeric antibodies retain the antigen specificity and affinity of the parental antibody, but exhibit a longer half-life and greater ability to mediate CDC and ADCC responses. As one of the professional bio-manufacturers, Alpha Lifetech Inc. is becoming an expert in the field of antibody engineering. We offer a wide range of unique services, including antibody humanization, expression of full-length chimeric antibodies and large-scale production of single-domain antibodies (sdAbs).
Phage Display Library – Chimeric Antibody Production Services
A chimeric antibody (cAb) is an antibody made by fusing the antigen binding region (variable domains of the heavy and light chains, VH and VL) from one species like a mouse, with the constant domain (effector region) from another species such as a rabbit. Chimeric antibodies retain the antigen specificity and affinity of the original antibody but reduce the risk of reaction to foreign antibodies from a non-SELF source when used in the clinic. The chimeric antibodies are valuable tools for in vitro and in vivo research.
Applications of chimeric antibodies in vitro:
-- Chimeric antibodies allow the antibody to be tailored to a specific application without being limited by the original antibody species
-- Chimeric antibodies allow the researcher the flexibility to adapt the monoclonal antibody of their choice to any platform or binding module/surface whilst retaining the original antibody's specificity and sensitivity for a particular antigen, such as protein microarray (chip) platforms or support beads.
-- Flow cytometry and IHC: Chimeric antibodies can circumvent potential non-specific binding issues associated with secondary antibody binding to the test cell or tissue (a common problem for Flow Cytometry and IHC).
-- Chimeric antibodies for assay development and diagnostics: Use as calibrators (standards) or controls in immunoassays - Serological immunoassays have been designed to detect a specific antibody in patient samples rely on serum calibrators (standards) and or positive controls.
Calibrators can be used in an immunoassay to generate standard curves to quantify the test antibody concentration in the patient serum and or as positive controls to assess the performance of the assay and reagents. Take the pneumonia polysaccharide vaccine as an example, turbidity Immunoassay, a serological immunoassay, often uses the anti-serum (polyclonal antibody from goat, sheep or rabbit) as a calibrator to quantify the potency of anti-serum from human beings. The value of coefficient of variation (CV value) varied significantly from -40% to +40%, because the calibrator is derived from seropositive serum or plasma and is heterogeneous by nature and thus suffers from significant drawbacks including:
-- Lot to lot variability concerning to antibody class IgG, IgM composition, specificity and affinity
-- Difficulty in sourcing large amounts with high titer
-- Limitations in characterization
Chimeric antibodies as calibrators or positive controls offer a viable and more reliable alternative to serum-based calibrators. The advantages of using chimeric antibody calibrators (standards) or positive controls in immunoassays are:
-- CV value among lots can be less than 5%
-- Large-size quantities are available and homogeneous in specificity and affinity
-- Fully characterized calibrator, stable potency and detailed compositions
-- Chimeric antibody calibrators are applicable to any diagnostic immunoassays
Applications of chimeric antibodies in vivo:
There are two mainly applications of chimeric antibodies: Antibody chimerization is a preliminary step before antibody humanization in order to associate biological function to parental antibody and to decrease its immunogenicity. Alternatively, chimeric antibodies can be employed for therapeutic purposes in particular diseases or under certain conditions (variable domain with high GI). The second one is diagnostic use: Chimeric antibodies are the best alternative to serum, calibrators and positive controls in diagnostics assays. They are particularly suitable as they can be produced in unlimited quantities and homogeneous (preservation of antibody specificity and affinity.
Alpha Lifetech Inc. has developed a proprietary strategy for the rapid production of chimeric antibodies including full-length rat/human, mouse/human, mouse/rabbit, rat/rabbit and other hybrid antibodies. Our proprietary chimeric antibody technology allows you to specify your requirements for expression and characterization. Our scientists have extensive experience in constructing and expressing recombinant or chimeric antibodies of various isotypes, including modified constant regions. We also specialize in expression in mammalian cells using our recombinant mammalian expression systems.
For more information about this program and to receive a custom quotation, please feel free to contact us at any time.