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To facilitate treatment and limit transmission of tuberculosis (TB), new methods are needed to enable rapid and affordable diagnosis of the disease in high-burden low-resource settings. We have developed a prototype integrated nucleic acid testing device to detect Mycobacterium tuberculosis (M.tb) in sputum. The device consists of a disposable cartridge and compact, inexpensive instrument that automates pathogen lysis, nucleic acid extraction, isothermal DNA amplification and lateral flow detection. A liquefied and disinfected sputum sample is manually injected into the cartridge, and all other steps are automated, with a result provided in

Next-generation sequencing (NGS) can identify and validate new biomarkers of cancer onset, progression and therapy resistance. Substantial archives of formalin-fixed, paraffin-embedded (FFPE) cancer samples from patients represent a rich resource for linking molecular signatures to clinical data. However, performing NGS on FFPE samples is limited by poor RNA purification methods. To address this hurdle, we developed an improved methodology for extracting high-quality RNA from FFPE samples. By briefly integrating a newly-designed micro-homogenizing (mH) tool with commercially available FFPE RNA extraction protocols, RNA recovery is increased by approximately 3-fold while maintaining standard A260/A280 ratios and RNA quality index (RQI) values. Furthermore, we demonstrate that the mH-purified FFPE RNAs are longer and of higher integrity. Previous studies have suggested that pancreatic ductal adenocarcinoma (PDAC) gene expression signatures vary significantly under in vitro versus in vivo and in vivo subcutaneous versus orthotopic conditions. By using our improved mH-based method, we were able to preserve established expression patterns of KRas-dependency genes within these three unique microenvironments. Finally, expression analysis of novel biomarkers in KRas mutant PDAC samples revealed that PEAK1 decreases and MST1R increases by over 100-fold in orthotopic versus subcutaneous microenvironments. Interestingly, however, only PEAK1 levels remain elevated in orthotopically grown KRas wild-type PDAC cells. These results demonstrate the critical nature of the orthotopic tumor microenvironment when evaluating the clinical relevance of new biomarkers in cells or patient-derived samples. Furthermore, this new mH-based FFPE RNA extraction method has the potential to enhance and expand future FFPE-RNA-NGS cancer biomarker studies.

Recent studies regarding the origins of life and Mars-Earth meteorite transfer simulations suggest that biological informational polymers, such as nucleic acids (DNA and RNA), have the potential to provide unambiguous evidence of life on Mars. To this end, we are developing a metagenomics-based life-detection instrument which integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG). Our goal is to isolate and sequence nucleic acids from extant or preserved life on Mars in order to determine if a particular genetic sequence (1) is distantly related to life on Earth, indicating a shared ancestry due to lithological exchange, or (2) is unrelated to life on Earth, suggesting a convergent origins of life on Mars. In this study, we validate prior work on nucleic acid extraction from cells deposited in Mars analog soils down to microbial concentrations (i.e., 104 cells in 50 mg of soil) observed in the driest and coldest regions on Earth. In addition, we report low-input nanopore sequencing results from 2 pg of purified Bacillus subtilis spore DNA simulating ideal extraction yields equivalent to 1 ppb life-detection sensitivity. We achieve this by employing carrier sequencing, a method of sequencing sub-nanogram DNA in the background of a genomic carrier. After filtering of carrier, low-quality, and low-complexity reads we detected 5 B. subtilis reads, 18 contamination reads (including Homo sapiens), and 6 high-quality noise reads believed to be sequencing artifacts.

The International Space Station (ISS) National Laboratory is dedicated to studying the effects of space on life and physical systems, and to developing new science and technologies for space exploration. A key aspect of achieving these goals is to operate the ISS National Lab more like an Earth-based laboratory, conducting complex end-to-end experimentation, not limited to simple microgravity exposure. Towards that end NASA developed a novel suite of molecular biology laboratory tools, reagents, and methods, named WetLab-2, uniquely designed to operate in microgravity, and to process biological samples for real-time gene expression analysis on-orbit. This includes a novel fluidic RNA Sample Preparation Module and fluid transfer devices, all-in-one lyophilized PCR assays, centrifuge, and a real-time PCR thermal cycler. Here we describe the results from the WetLab-2 validation experiments conducted in microgravity during ISS increment 47/SPX-8. Specifically, quantitative PCR was performed on a concentration series of DNA calibration standards, and Reverse Transcriptase-quantitative PCR was conducted on RNA extracted and purified on-orbit from frozen Escherichia coli and mouse liver tissue. Cycle threshold (Ct) values and PCR efficiencies obtained on-orbit from DNA standards were similar to Earth (1 g) controls. Also, on-orbit multiplex analysis of gene expression from bacterial cells and mammalian tissue RNA samples was successfully conducted in about 3 h, with data transmitted within 2 h of experiment completion. Thermal cycling in microgravity resulted in the trapping of gas bubbles inside septa cap assay tubes, causing small but measurable increases in Ct curve noise and variability. Bubble formation was successfully suppressed in a rapid follow-up on-orbit experiment using standard caps to pressurize PCR tubes and reduce gas release during heating cycles. The WetLab-2 facility now provides a novel operational on-orbit research capability for molecular biology and demonstrates the feasibility of more complex wet bench experiments in the ISS National Lab environment.

Due to meteoritic transfer between Earth and Mars, if life on Mars exists, it may be related to life on Earth and utilize nucleic acids as informational polymers. Thus, a Search for Extra-Terrestrial Genomes (SETG) could detect and sequence (deoxy)ribonucleic acids (DNA/RNA) utilized by any extant or recently dead life on Mars. The abiotic synthesis of common organic building blocks, such as nucleobases, sugars, and amino acids, in the solar nebula and potentially in diverse habitable environments could also bias a second genesis of life towards utilizing informational polymers similar to life as we know it. Here we build on prior work and describe the advancement of a SETG instrument to technology readiness level 4 through sample-to-sequence processing with limited manual handling. Another advance includes validation of nucleic acid extraction from Mars analogs at cell counts down to 104 per 50 mg sample, equivalent to a limit of detection of approximately 1 part per billion. In addition, we demonstrate that biological nanopore-based single molecule sequencing can be used to detect non-standard bases. Finally, we link sequence data to a statistical test to distinguish between any forward contamination and putative life beyond Earth. Nanopore-based sensing may ultimately enable characterization of non-standard polymers and other molecules, highlighting the potential for nanopore-based life detection and sequencing on Mars or other words such as the icy moons Enceladus or Europa.

Nucleic acid amplification testing (NAAT) enables rapid and sensitive diagnosis of tuberculosis (TB), which facilitates treatment and mitigates transmission. Nucleic acid extraction from sputum constitutes the greatest technical challenge in TB NAAT for near-patient settings. This report presents preliminary data for a semi-automated sample processing method, wherein sputum is disinfected and liquefied, followed by PureLyse® mechanical lysis and solid-phase nucleic acid extraction in a miniaturized, battery-operated bead blender. Sputum liquefaction and disinfection enabled a >104 fold reduction in viable load of cultured Mycobacterium tuberculosis (M.tb) spiked into human sputum, which mitigates biohazard concerns. Sample preparation via the PureLyse® method and a clinically validated manual method enabled positive PCR-based detection for sputum spiked with 104 and 105 colony forming units (cfu)/mL M.tb. At 103 cfu/mL sputum, four of six and two of six samples amplified using the comparator and PureLyse® method, respectively. For clinical specimens from TB cases and controls, the two methods provided 100% concordant results for samples with "Equation missing"1 mL input volume (N = 41). The semi-automated PureLyse® method therefore performed similarly to a validated manual comparator method, but is faster, minimally instrumented and can be integrated into TB molecular diagnostic platforms designed for near-patient low-resource settings.

Two mechanical lysis devices have been developed as compact, robust components to provide rapid sample preparation for nucleic acid diagnostic systems. One such component, known as the Micro Bead-Beater™ (μBB™, BBTM, Claremont BioSolutions, Upland, CA), is a compact device that is capable of ultrarapid lysis (>90% lysis in 30 s) of micro volumes (

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths. Because there are virtually no biomarkers to aid in early detection or predicting therapy response, newly diagnosed patients have a dismal prognosis. Substantial archives of formalin-fixed, paraffin-embedded (FFPE) samples from PDAC tissue have been established and linked to clinical data. However, identifying biomarkers from these tumors is severely hindered because extracting high-quality nucleic acid material from FFPE samples is time-consuming and inefficient. Thus, developing improved methods for extracting high-quality RNA/DNA from FFPE samples represents an unmet need in the fields of cancer biology and Next-Generation Sequencing (NGS). We have tested Claremont BioSolutions’ microhomogenization (mH) tools in combination with commercial FFPE RNA extraction kits for their ability to improve high-quality RNA recovery from PDAC xenograft samples. Our results demonstrate that the addition of brief (< 5min) mH s...

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths. There are virtually no biomarkers to aid in early detection or predicting therapy response, newly diagnosed patients have less than a 7% 5-year survival rate and the median survival from the time of diagnosis is less than 12 months. Next-Generation Sequencing (NGS) together with in vitro/in vivo functional studies is likely to identify and validate new biomarkers of PDAC onset, progression and therapy resistance. Importantly, the substantial archives of formalin-fixed, paraffin-embedded (FFPE) samples from PDAC patients are likely to be a rich resource for linking molecular signatures to relevant clinical data. However, NGS methods on FFPE samples are severely hindered because extracting high-quality nucleic acid material from these samples is time-consuming and inefficient. We have sought to develop novel methods for improving the extraction of high-quality RNA from FFPE samples within the context of commercially-available FFPE RNA kits and protocols. Together with researchers and clinicians at Claremont BioSolutions, AntiCancer Inc. and UCSD our laboratory has developed a novel nucleic acid extraction method that significantly increases RNA yield and integrity from PDAC cell line and Patient-Derived Xenograft FFPE samples. By briefly ( Citation Format: Malachia Hoover, Yvess Adamian, Mark Brown, Ali A. Maawy, Robert Hoffman, Michael Bouvet, Robert Doebler, Jonathan A. Kelber. Analysis of microenvironment effects on pancreatic cancer biomarker expression using a novel method for FFPE RNA extraction. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-263.

Molecular detection of microorganisms requires microbial cell disruption to release nucleic acids. Sensitive detection of thick-walled microorganisms such as Bacillus spores and Mycobacterium cells typically necessitates mechanical disruption through bead beating or sonication, using benchtop instruments that require line power. Miniaturized, low-power, battery-operated devices are needed to facilitate mechanical pathogen disruption for nucleic acid testing at the point of care and in field settings. We assessed the lysis efficiency of a very small disposable bead blender called OmniLyse relative to the industry standard benchtop Biospec Mini-BeadBeater. The OmniLyse weighs approximately 3 g, at a size of approximately 1.1 cm 3 without the battery pack. Both instruments were used to mechanically lyse Bacillus subtilis spores and Mycobacterium bovis BCG cells. The relative lysis efficiency was assessed through real-time PCR. Cycle threshold ( C T ) values obtained at all microbial cell concentrations were similar between the two devices, indicating that the lysis efficiencies of the OmniLyse and the BioSpec Mini-BeadBeater were comparable. As an internal control, genomic DNA from a different organism was spiked at a constant concentration into each sample upstream of lysis. The C T values for PCR amplification of lysed samples using primers specific to this internal control were comparable between the two devices, indicating negligible PCR inhibition or other secondary effects. Overall, the OmniLyse device was found to effectively lyse tough-walled organisms in a very small, disposable, battery-operated format, which is expected to facilitate sensitive point-of-care nucleic acid testing.