With our superior bispecific antibodies (BsAbs) production platforms, Creative Biolabs is capable of providing customers versatile bispecific antibodies with higher sensitivity and reproductively.
BsAbs are engineered macromolecules with two or more distinct binding specificities within one molecule. They are excellent diagnostic immunoprobes as they can simultaneous bind to one antigen and one marker enzyme (forced protein association). BsAbs have been used in a number of diagnostic applications such as immunoassays, radioimmunodiagnosis, and immunohistochemistry. Detection is more sensitive, rapid and specific with the help of BsAbs. Another advantage of applying BsAbs in the application of diagnostics is that BsAb diagnostic reagents avoid batch to batch variations. In the case of immunohistochemistry and immunodiagnostic assays, BsAb-mediated reactions have also improved the signal to noise ratio and simplified procedure.
Chemical conjugation of the antibody with the detection moiety can be not needed when BsAbs are used. This eliminates the possibility of aggregations and/or inactivation of the molecule that may occur during chemical conjugation. Comparing to previous reagents, BsAbs ensure the antibody: detection moiety ratio to be 1:1 and ensure the uniformity of the products, which are critical for immunohistochemical reactions. Also, BsAbs for diagnostic applications are purified along with tagging, which simplifies the production procedure. Therefore, BsAb diagnostic reagents have great potentials in the application of diagnostics, as they are uniform, homogenous and have reproducible high specific activity. BsAbs have already been applied in different areas of diagnostics. BsAbs can function as detection antibodies for diagnosis of infectious diseases caused by bacterial and viral infections, and different types of cancers. Mycobacterium tuberculosis, Bordetella pertussis, Escherichia coli O157:H7, Severe Acute Respiratory Syndrome (SARS) Coronavirus, Dengue Virus, and Prostate Cancer are some pathogens/diseases that BsAbs have been used to detect.
Figure 1. This figure shows the cell imaging of BsAb modified NPs. The SW480 (EGFR þ) and SW620 (EGFR À) cells were incubated with aEGFR-Lipo/Rho. The cells were fixed, stained with DAPI and then examined under a confocal microscopy. (Kao, C. H., 2014)
BsAbs for diagnostic applications normally are tagged with enzymes [horse radish peroxidase (HRPO), alkaline phosphatase, or b-galactosidase, etc.] during purification. In immunoassays, commonly a solid phase is coated with a pathogen antigen-specific antibody and then incubated with the clinical specimen. The pathogen then specifically binds to the antibody through antigen-antibody interaction. After washing off other unbound materials, the purified BsAb is added as the detection antibody. One arm of the BsAb recognizes the antigen, while the other arm is tagged with the enzyme (e.g., HRPO). Last, enzyme substrate [e.g., 3, 30, 5, 50-tetramethylbenzidine (TMB) for HRPO] is added and specific color (e.g., blue for HRPO-TMB reaction) is formed as an indication of the presence of the pathogen. If generated based on specific tumor-associated antigens (TAA), BsAbs can be used in cancer diagnostics as well. It has been reported that an anti-PSA BsAb can be produced by hybrid-hybridoma technology. This BsAb recognizes the prostate-specific antigen (PSA) in the serum and is widely used for screening and monitoring the progression of prostate cancer.
As one of leader biotechnology companies in BsAb development, Creative Biolabs is dedicated to providing versatile BsAbs with the superior production platforms. We are here to assist your research for both scientific and clinical purposes.
1. Kao, C. H.; et al. One-step mixing with humanized anti-mPEG bispecific antibody enhances tumor accumulation and therapeutic efficacy of mPEGylated nanoparticles. Biomaterials. 2014, 35(37): 9930-9940.
2. Byrne, H.; et al. A tale of two specificities: bispecific antibodies for therapeutic and diagnostic applications.” Trends in biotechnology. 2013, 31(11): 621-632.