Novel Saliva-based Renal Function Test Platform

Project Summary Chronic Kidney DiseaseCKDaffects millions of people worldwideincludingmillion adults and children in the USATimely detection of kidney function deterioration can improve management of CKDincluding in kidney transplanted recipientsWithout a blood drawan acute kidney injuryAKIevent or a transplant rejection could remain unrecognized for extended periods of timeleading to irreversible loss of kidney function and structureNovel patient friendly methods of kidney function measurement with high levels of precision and reproducibility are urgently needed to ensure more frequent and reliable monitoring in the home and for point of care screeningCurrentlyinvasive phlebotomy followed by laborious blood specimen processing and reporting are the only way to measure the three major kidney filtration markersserum creatinineureaand cystatin CHoweversaliva has been proven to mirror blood biomarker levelsLimited preliminary data suggest that salivary creatinine and urea levels correlate with those in serum in CKD patientsMeasurable levels of cystatin C have been assayed in saliva without being affected by periodontal diseaseBased on these findingsIntelligent Optical SystemsIOSin collaboration with the University of CaliforniaUCIrvine and UC San Franciscoplans to developPhase Imonthsa novel means of detecting creatininecystatin Cand urea in salivausing a highly sensitive and selective enzyme based lateral flow assayELF assayIn this novelcompactsingle stepenzymatic multiplexed assayhighly fluorescent dyes yield reliable quantitative measurements on a portable analyzerThe innovatively developed methods will be subsequentlyFast Trackvalidated inCKD patients from UCI nephrology and transplant clinicsPhase IImonthsThe proposed development builds on extensive IOS expertise in complex assay developmentusing saliva matrix that has been successfully validated in clinics for bone metabolism markers and rapid testing for drug of abuseIn Phase I we will demonstrate the feasibility of recording reproducible and sensitive measurements of salivary creatininecystatin Cand ureausing spiked and laboratory tested human saliva samples obtained from BioreclamationIVTAssay specificationsensitivity LODspecificityand stability will be reported by the end of Phase I in accordance with IOS established protocols for salivary assay development and optimizationBuilding on a successful Phase I demonstration of an ELF assayand validating the results against the predetermined milestone criteriawe will then conduct the clinical validation in Phase IItesting saliva measurements against blood levels inhuman subjects with CKDincludingkidney transplant recipientswith a broad range of GFR ofmL minmBSAOur proposed Fast Track design is efficientfeasibleand innovativeand has a high likelihood of sustained powerful influence and immediate clinical applicabilityThe availability of non invasivepoint of caremultiplex measures of kidney function would have a dramatic impact on the care and monitoring of patients with CKDparticularly in remote locations Project Narrative Intelligent Optical Systemsin collaboration with the University of California Irvine Nephrology and transplant Centersproposes to develop a novel rapid technique for measuring three kidney function markers in salivaThe device will be portable for rapid bedside measurement of saliva samples acquired noninvasively from patients in point of care and home settingsand for rapid screeningThe multiplexed measurements of the target markers will not only be a reliable and reproducible measure of kidney filtration functionbut will also be an early predictor of CKD progression or acute worsening of kidney function in transplanted patients