Particle display: a new paradigm in high throughput discovery of ultra-high perfo

DESCRIPTION provided by applicant Nucleic acid aptamers have shown great promise as the synthetic alternative to monoclonal antibodies in therapeutics diagnostics and Randamp D tools Key advantages of aptamers comparing to antibodies include applicability to non immunogenic targets chemical and thermal stability low production cost and no batch to batch variation Nevertheless the potential of aptamers has not been fully realized due to the bottleneck in the discovery process to date the methods used to discover aptamers have been exclusively selection based i e SELEX Unfortunately these methods often fail to discover the highest performance aptamer in the starting library due to a multitude of interfering factors such as library synthesis bias PCR bias and non specific binding Furthermore previous investigations suggest that these methods may discover DNA aptamers for only of the human proteome greatly limiting aptamersandapos application scope Previous innovations in the discovery process are all variants of SELEX and mainly focus on improving selection efficiency in consequence the fundamental aptamer performance issue has not yet been solved The purpose of this SBIR project is to develop a screening based method referred as andquot Particle Displayandquot or andquot PDandquot in this proposal that overcomes the aptamer discovery barrier We display each aptamer in the library on an aptamer particle AP at copies which allows us to use FACS to quantitatively measure the binding property of the aptamer on each AP in an ultra high throughput fashion PD thus enables precise isolation of aptamers that pass a defined performance threshold Moreover we can use multi color FACS to simultaneously measure multiple fluorescence wavelengths of the APs each wavelength representing one binding property and thus uniquely enable screening of multiple favorable binding properties such as affinity specificity and binding kinetics The hypothesis of this project is that PD can overcome the limitations of conventional selection based methods and enable efficient discovery of the highest performance aptamers In Phase I we propose to first develop the PD platform for screen for high target affinity We will then work to develop multi color PD to simultaneously screen for multiple binding properties In Phase II we will use multi color PD to screen for aptamer pairs to enable sandwich assays to screen for application ready aptamers in biological samples and validate universal applicability of PD in different target types At the end of phase II we expect to have established the capability of Particle Display in developing high performance aptamers in a high throughput manner which can serve various unmet needs in therapeutics diagnostics and life science Randamp D PUBLIC HEALTH RELEVANCE Nucleic acid aptamers have shown great promise as the synthetic alternative to monoclonal antibodies in therapeutics diagnostics and Randamp D tools However the potential of aptamers has not been fully realized due to the bottleneck in the discovery process The purpose of this SBIR project is to develop a screening based method designated as andquot Particle Displayandquot that we believe will overcome the aptamer discovery barrier and satisfy the growing unmet needs for high performance affinity reagents in therapeutics diagnostics and life science Randamp D