title: Cholestyramine as a promising, strong anion exchange resin for direct capture of genetic biomarkers from raw pancreatic fluids.
abstract: The ability to capture cell-free DNA from the gastrointestinal tract, in a minimally invasive manner, could enhance our ability to diagnose gastrointestinal disease, or gain a better understanding of the spatial mapping of the intestinal microbiota. We, therefore, sought to identify a class of capture agents that could directly and efficiently sequester genetic material from intestinal fluids. As a particular case study, we examined the ability to capture DNA from pancreatic secretions, for potential application in enabling the sequestration of early, genetic biomarkers of pancreatic disease. We hypothesized that the cholestyramine series of strong cation exchange resins, which are FDA approved for the treatment of high cholesterol, may be capable of capturing DNA from pancreatic secretions. We identified a particular cholestyramine resin, DOWEX 1 × 2 100-200 mesh, which is able to efficiently capture and purify DNA from pancreatic fluid. Using only 200 μL of pancreatic secretions, we are able to recover 247 ± 182 ng of amplifiable human DNA, giving an estimated pancreatic fluid DNA content of 1.23 ± 0.91 ng/μL. To our knowledge, this is the first demonstration of a material that can effectively capture and purify DNA directly from untreated pancreatic fluids. Thus, our approach could hold high utility for the in vivo capture of DNA and disease biomarkers if incorporated into an appropriate sampling device. Biotechnol. Bioeng. 2017;114: 934-938. © 2016 Wiley Periodicals, Inc.
authors: Departments of Chemistry, Chemical Engineering, and Biochemistry, Stanford University, Stanford 94305, California.
authors: Andrew J
authors: AJ
authors: Hilmer
authors: Department of Radiology, Stanford University Medical Center, Stanford, California.
authors: R Brooke
authors: RB
authors: Jeffrey
authors: Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University Medical Center, Stanford, California.
authors: Walter G
authors: WG
authors: Park
authors: Departments of Chemistry, Chemical Engineering, and Biochemistry, Stanford University, Stanford 94305, California.|Stanford ChEM-H, Stanford, California.
authors: Chaitan
authors: C
authors: Khosla
mesh_terms: D000837:Anion Exchange Resins / Q000737:chemistry* / Q000378:metabolism; D002460:Cell Line; D002792:Cholestyramine Resin / Q000737:chemistry* / Q000378:metabolism; D004247:DNA / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D005819:Genetic Markers / Q000235:genetics*; D006801:Humans; D008954:Models, Biological; D010189:Pancreatic Juice / Q000737:chemistry*
chemical_list: D000837:Anion Exchange Resins; D005819:Genetic Markers; D002792:Cholestyramine Resin; D004247:DNA
keywords: biomarker; cell-free DNA capture; cholestyramine; intestine; pancreatic fluid