Accelerating Antibody Production
“The critical feature of our technology is our newly developed MultiPure purification platform of fusion products,” states Nathalie Forster, product development and support manager for R&D at Maine Biotechnology Services (MBS). With the Multipure platform, one can normalize assays, perform biotin conjugations, and measure epitope compatibility for 96 or more clones simultaneously, she says.
In an effort to generate monoclonal antibodies to equine luteinizing hormone (eLH) suitable for the veterinary reproductive diagnostic market, MBS recently embarked upon a collaborative effort with James Weber, Ph.D., DVM, of the University of Maine. LH triggers ovulation and is critical for the reproductive process, which tends to be tenuous in horses and unresponsive to conventional reproductive technologies.
Accurate measurement of eLH levels would allow optimal timing of breeding and favor successful fertilization. It would also provide insight about when to terminate the process, as conventional tools reveal a broad window of several days, which adds to the expense. The goal of this project was to develop a prototype matched-pair sandwich assay sensitive and accurate enough to detect physiological eLH levels.
According to Dr. Forster, the success of the antibody-development project is contingent upon the integrity of the immunizing and screening reagents, the ability of the screening strategy to discern fusion products of interest, and the capability to characterize the resulting antibodies for use in the end application.
The ability to analyze the biological and physical characteristics of the fusion products at an early stage in the hybridoma process allows critical decisions to be made concerning choices for subcloning, production, and purification. This approach is ideal for the development of antibodies destined for diagnostics and matched pair applications. The protocol takes advantage of a 21-day rapid immunization strategy with a fusion done on day 28. The fusion screening typically occurs approximately 14 days post-fusion.
The MultiPure purification platform allows many clones of interest to be simultaneously grown and purified, with normalization of production rates so affinities can be compared.
By narrowing down a large number of clones and making pairwise assessments it was possible to isolate the highest performing combinations of monoclonal antibodies to be used in a diagnostic assay, Dr. Forster adds.
The resultant antibody pair and prototype assay were used to evaluate daily serum samples from mares taken through the course of one estrous cycle. In parallel, measurements of the dominant follicle and progesterone levels were assayed using a commercially available test kit. Serum samples were run on a quantitative MBS prototype eLH assay. The results on the serum samples provided insight as to what the optimum breeding time would have been, validating the assay and concept.
“With the successful outcome of this study we are making our MultiPure technology available as a service to our Hybridoma customers,” Dr. Forster says.
Biotech companies keep returning to the problems of narrowing down candidate diagnostics and therapeutics, a process that can entail substantial costs and extended time frames. The approaches discussed here entail new ways of looking at old problems and applying newly developed hardware and software to resolving them. Venture capital funds have virtually disappeared for all but the furthest late-stage products, so biotechs could profit from the opportunity to speed preclinical development to completion.