title: Molecular Detection of Schistosome Infections with a Disposable Microfluidic Cassette.
abstract: Parasitic helminths such as schistosomes, as well as filarial and soil-transmitted nematodes, are estimated to infect at least a billion people worldwide, with devastating impacts on human health and economic development. Diagnosis and monitoring of infection dynamics and efficacy of treatment depend almost entirely on methods that are inaccurate, labor-intensive, and unreliable. These shortcomings are amplified and take on added significance in mass drug administration programs, where measures of effectiveness depend on accurate monitoring of treatment success (or failure), changes in disease transmission rates, and emergence of possible drug resistance. Here, we adapt isothermal molecular assays such as loop-mediated isothermal amplification (LAMP) to a simple, hand-held, custom-made field-ready microfluidic device that allows sensitive and specific detection of schistosome cell-free nucleic acids in serum and plasma (separated with a point-of-care plasma separator) from Schistosoma mansoni-infected mice. Cell-free S. mansoni DNA was detected with our device without prior extraction from blood. Our chip exhibits high sensitivity (~2 x 10(-17) g/μL), with a positive signal for S. mansoni DNA detectable as early as one week post infection, several weeks before parasite egg production commences. These results indicate that incorporation of isothermal amplification strategies with our chips could represent a strategy for rapid, simple, low-cost diagnosis of both pre-patent and chronic schistosome infections as well as potential monitoring of treatment efficacy.
authors.affiliation: Department of Mechanical Engineering and Applied Mechanics, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Jinzhao
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Mechanical Engineering and Applied Mechanics, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Changchun
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Swarna
authors.initials: S
authors.lastname: Bais
authors.affiliation: Department of Mechanical Engineering and Applied Mechanics, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Mauk
authors.affiliation: Department of Mechanical Engineering and Applied Mechanics, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Haim H
authors.initials: HH
authors.lastname: Bau
authors.affiliation: Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Greenberg
mesh_terms: D000818:Animals; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D005260:Female; D006801:Humans; D051379:Mice; D044085:Microfluidics / Q000379:methods*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D019095:Point-of-Care Systems; D012550:Schistosoma mansoni / Q000235:genetics / Q000302:isolation & purification*; D012555:Schistosomiasis mansoni / Q000175:diagnosis* / Q000469:parasitology; D013997:Time Factors
chemical_list: D018509:DNA, Helminth