Glucagon Monoclonal Antibodies

Rabbit monoclonal antibodies for Glucagon

Proteolytic cleavage of the protein precursor proglucagon leads to the production of the peptide hormone glucagon.   However, proglucagon is also metabolized into a family of peptides which share sequence homology with the hormone.  This includes some with an identical amino or carboxy terminus. This shared sequence homology makes it challenging to develop antibodies that are highly specific for the active form. Therefore, we designed a strategy to generate antibody clones that recognize either the amino terminus or the carboxy terminus of glucagon in a NH2⁺ or COO^– group dependent manner.  Thus the pair of NH2⁺ and COO^– dependent antibody clones together in a sandwich ELISA setting will only recognize the active form of glucagon.

The two antibody clones chosen can form a pair in sandwich ELISA that is highly specific to only the active hormone. Both antibodies show no cross-reactivity to proglucagon or other metabolites derived from the proglucagon, such as mini-glucagon and oxyntomodulin.  The apparent affinity for both antibodies is approximately 50 pM.  Together, in a sandwich ELISA, these antibodies can detect as low as 10 pg/mL glucagon with a linear range up to 220 pg/mL. Since this is much lower than the average level in normal individual’s plasma (200 pg/mL), these antibodies can be useful in developing a highly sensitive and specific ELISA for accurate measurement of glucagon levels in human plasma.

Figure 1. Sensitivity and linear range of Sandwich ELISA.  The use of anti-Glucagon DA-2013 as the capture antibody and anti-Glucagon DA-2014 as the detection antibody allows the detection of as little as 10 pg/mL to greater than 220 pg/mL of human glucagon.

References

1. Mishra AK, Dubey V, and Ghosh AR (Jan 2016). “Obesity:  An overview of possible role(s) of gut hormones, lipid sensing, and gut microbiota”. Metabolism 65 (1): 48–65.