Johns Hopkins University

Andrew B Feldman

Jeffrey S Lin

Plamen A Demirev

David A Weitz

Peter F Scholl

Andrew S Pekosz

John Heyman

Nathan A Hagan

Miquel D Antoine

Rengaswamy Srinivasan

David J Sullivan

Hassan M Saffarian

Christiane Wobus

Assaf Rotem

Joshua T Wolfe

Nirbhay Kumar

Kellogg Schwab

Jared D Evans

Jefffrey S Lin

Darin Kongkasuriyachai

Timothy Julian

Methods for analyzing DNA-containing samples are provided. The methods can comprise isolating a single genomic equivalent of DNA from the DNA-containing sample to provide a single isolated DNA molecule. The single isolated DNA molecule can be subjected to amplification conditions in the presence of one or more sets of unique molecularly tagged primers to provide one or more amplicons. Any spurious allelic sequences generated during the amplification process are tagged with an identical molecular tag. The methods can also include a step of determining the sequence of the one or more amplicons, in which the majority sequence for each code is selected as the sequence of the single original encapsulated target. The DNA-containing sample can be a forensic sample (e.g., mixed contributor sample), a fetal genetic screening sample, or a biological cell.

Analysis of DNA-containing samples and resolution of mixed contributor DNA samples

A microfluidic assembly may include a microfluidic chip operably coupled to a device source pressure port and a device relief pressure port, first and second input reservoirs, an output reservoir, and a reservoir interface. The microfluidic chip may include a microfluidic circuit configured to support a fluid flow that includes a gas flow and a liquid flow within the microfluidic circuit. The reservoir interface may be configured to operably couple the first and second input reservoirs to the microfluidic circuit. The device source pressure port may be configured to receive a source pressure to generate the fluid flow through the microfluidic circuit and cause a mixing of liquids to form an output liquid for delivery to the output reservoir via the fluid flow. The first liquid, the second liquid, and the output liquid need not contact the device source pressure port or the device relief pressure port during the mixing.

Microfluidic device with reservoir interface

Food products and/or pharmaceutical preparations including (i) viral neutralizing antibodies or antibody fragments anchored to a probiotic microorganism and (ii) a carrier medium for delivering the viral neutralizing antibodies or antibody fragments anchored to probiotic microorganisms to the gut of a mammal. Also provided are methods of making food products and/or pharmaceutical preparations, which can be used to treat existing viral infections or prevent the spread or transmission of viral infection.

Compositions and methods for preventing or relieving symptoms of infections

A method for synthesizing an antiserum for rapid-turnaround therapies includes collecting antibody-secreting cells from a test subject, wherein the test subject has been exposed to a target biological agent and has produced an antibody response; selecting a subset of the antibody-secreting cells, the subset of the antibody-secreting cells producing antibodies that neutralize the target biological agent; generating variable-region-coding DNA sequences from the antibodies that neutralize the target biological agent; tagging amplicons of the variable-region-coding DNA sequences with unique nucleic acid identifiers to associate the variable-region-coding DNA sequences derived from individual ones of the subset of the antibody-secreting cells; analyzing antibody-type distribution in a natural immune response; synthesizing antibodies from the variable-region-coding DNA sequences to form synthetic antibodies; and mixing the synthetic antibodies in a proportion equal to the antibody-type distribution in the natural immune response to form the antiserum.

Synthetic antiserum for rapid-turnaround therapies

Certain embodiments of the present invention include a method for rapidly designing pharmaceutical preparations for preventing viral infection that have adapted to growth in various culturing systems but maintain antigenic similarity to the original virus. The method may include serial passaging a plurality of instances of a targeted virus strain from an infected first animal in respective droplets in second animal cells, in parallel synthesizing antibodies that neutralize the targeted virus strain in a third animal, and selecting the second animal cell-adapted viral lineages that are neutralized by the antibodies to identify second animal cell-adapted viral lineages having antigenic similarity to the targeted virus strain.

Method for rapidly designing pharmaceutical preparations for preventing viral infection

The present invention is based on the discovery that drug resistance in microorganisms can be rapidly and accurately determined using mass spectrometry. A mass spectrum of an intact microorganism or one or more isolated biomarkers from the microorganism grown in drug containing, isotopically-labeled media is compared with a mass spectrum of the intact microorganism or one or more isolated biomarkers from the microorganism grown in non-labeled media without the drug present. Drug resistance is determined by predicting and detecting a characteristic mass shift of one or more biomarkers using algorithms. The characteristic mass shift is indicative that the microorganism is growing in the presence of the drug and incorporating the isotopic label into the one or more biomarkers, resulting in change in mass.

System for determining drug resistance in microorganisms

Systems and methods for determining drug resistance in microorganisms

Mass spectrometric techniques are provided for detecting the presence of parasites that accumulate unbound heme in red blood cells (including malaria parasites), based on the discovery that unbound heme can be detected and quantified using mass spectrometry. In one aspect of the invention, the method includes the steps of: obtaining a blood sample from the animal; preparing a test sample on a support from the blood sample, and inserting the support into a mass spectrometer for analysis. Next one obtains a mass spectrum of the test sample and determines whether the mass spectrum contains a mass/charge signature of unbound heme. If it is determined that the mass spectrum of the test sample shows the mass/charge signature of unbound heme, the animal is diagnosed as infected with malaria parasites.

Detection of malaria parasites by mass spectrometry

Methods are described for detecting and quantifying occult blood in a biological sample using laser desorption mass spectrometry (LD MS). Biological samples that can be analyzed using various embodiments of the present invention include stool (fecal occult blood, FOB), and any bodily fluid including urine, cerebrospinal fluid and other bodily fluids. If the heme or heme metabolite is bound to protein, the sample is treated with acid before analysis to release the porphyrin. Some of the methods use LD MS with a time of flight analyzer (TOF) to detect and measure unbound heme, other hemoglobin metabolites and other molecules that have a porphyrin-based structure, e.g., bilirubin, biliverdin, protoporphyrin IX, and Zinc protoporphyrin in the biological sample. In other methods, matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is used to detect and quantify the individual &#x3b1;- and &#x3b2;-polypeptide chains of hemoglobin.

Occult blood detection in biological samples by laser desorption and matrix-assisted laser desorption/ionization mass spectrometry for biomedical applications

Provided are methods of producing an electrode capable of binding an analyte thereto comprising: providing a substrate capable of binding a dithiol molecule thereto; electrochemically treating the substrate using cyclic voltammetry to provide a treated substrate having a fractal dimension of greater than about 2; and contacting the treated substrate with dithiol molecules to produce an electrode having dithiol groups attached thereto and capable of binding an analyte to be detected thereto. Also provided are methods of accumulating and detecting analytes using the electrodes produced via the methods of the present invention.

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Columbia, MD, United States of America

Andrew B Feldman