Title: A Point-of-Care test for Sepsis based on Calcium-induced turbidity in Blood
Funder: Department of Health (England)

Abstract: Research Plan We have engaged a professional information search consultant (Harrison Goddard Foote Patent & Trademark Attorneys) for a prior art search to [1] determine if the inventions are novel against 3rd party disclosures, and [2] identify any published 3rd party patents/pending applications which might infringe the claims The conclusion was that no relevant prior art disclosures were found. Aims This project follows on from having established proof of feasibility for a point-of-care (POC) diagnostic device for the rapid detection of bacterial sepsis. i4i FPD1 II-FS-0509-12093 funding enabled us to show that a derivative of the aPTT test is possible on a disposable CD with an embedded mini-lab system. The challenges of converting a well-established biomarker assay to POC format have therefore been addressed. Our AIM with this proposal is to develop the established system into a fully functional POC prototype for clinical use in diagnosing sepsis. Specifically, we will advance the TRANSLATIONAL PIPELINE that;(a) began with our discovery of the aPTT biphasic waveform as a novel marker of bacterial sepsis [Int Care Med 2003;29:55], (b) patented a derivative calcium-based turbidity assay, and (c) established a compact disc (CD) delivery platform for a POC diagnostic test. Having addressed the inventive steps in whole blood separation, plasma transfer, valving and detection in the FD1 project, the technical challenges to deliver a POC unit can be broken down in to 5 distinct WORK PACKAGES. These will be: Work Package [1]. Optimization of initial CD design Deliverable 1a. Creation of end-user Disc Building on the work already completed with regard to laser rupture valves, microfluidic channels and reaction/separation chambers, the design focus will be on overall end-usability to achieve an easy-to-use and efficient CD. Plan1. Optimise sample loading procedures onto the disc.2. Optimise the microfluidic channels to minimise sample loss within the disc and reduce its overall size. Milestone 1a: Complete CD design incorporating optimised microfluidics and sample loading features Deliverable 1b. Production of Disc Currently, the disc is made by bonding two CNC machined halves together using an adhesive membrane. This method is slow and unsuitable for mass production. A new process will be investigated with respect to materials, disposability and cost. Plan 1. Evaluate method for mass production to replace the current method of CNC milling. These may include hot embossing or injection moulding.2. Once method is chosen, examples will be produced to assess their impact on the microfluidics and design. Our collaboration with 4dProducts will be important in the event of unexpected challenges. Their wealth of knowledge regarding product design and manufacture with useful links to manufacturing companies will allow us to overcome any issues. Milestone 1b: A complete production method for the microfluidic CD Work Package [2]. Optimization of hardware Deliverable 2a. Optimised Optical and Detector ComponentsThe light source and optical components will be improved, e.g. the 405nm lasers will be replaced with LED of similar wavelength. Detector components suited to 405nm will replace current components to increase accuracy of detection, analysis and operational robustness. Plan1. Evaluate the light source for maximal detection.2. Evaluate the detection system and replace components, as necessary. 3. Minimise power consumption of the detector system.4. Producing an improved detector system. In the event of sub-optimal resolution or accuracy in detection, we will look to source the entire detector from an external source and incorporate this into our design. Milestone 2a: Produce an accurate detector for the device Deliverable 2b. Optimised Electrical & Mechanical Components Electrical and mechanical components will be reconsidered to meet the operational demands of continual use. Plan 1. The electrical/mechanical components will be assessed. 2. Printed circuit boards will be designed and made.3. Safety devices will be incorporated.4. Total power consumption of the device will be reduced. In the event of technical challenges, we are able to rely on in-house electronics expertise in the University Department of Clinical Engineering in conjunction with external electronic manufacturing companies. Milestone 2b: Efficient electrical and mechanical components within the device Deliverable 2c. Optimised Motor Components Motor and motor-control used will be redressed to reduce its size, cost and power consumption. The external control will be removed and embedded into the bespoke software of the device. Plan 1. The motor type will be changed to a smaller and more efficient alternative. 2. The separate control of the motor will be incorporated into the embedded software written in work package 3. We will be able to seek advice, as necessary, from the suppliers of the current motor McLennan Servo Supplies to meet this milestone. Milestone 2c: Optimised motor and control components for the device Deliverable 2d. A fully functioning prototype device Further to completion of deliverable 2a -c and inclusion of the components needed to embed the software and safety components, the prototype device will be built. Plan 1. Consultation with 4D products to generate CAD designs for the product.2. Production of a prototype device. As in Work Package 1, 4d Products involvement will enhance our ability to address any technical challenges. Milestone 2d: A complete prototype device Work Package [3]. Bespoke Software Development Deliverable 3a. A bespoke software solution for the operation of the prototype deviceThe control and analysis software for the system have been developed on an external PC using National Instruments LabVIEW. This program will be embedded on a device within the system using either C or National instruments Compact RIO. Plan1. Evaluate the different packages available to write the bespoke software.2. The relevant hardware needed for embedding the software and for displaying the user interface will be determined.3. Functionality of the software with respect to Data collection/storage will be considered.4. Bespoke control software and data analysis will be written. Should software development be slower than expected, we will liaise with National Instruments or external programmers to write specific parts of the software. Milestone 3a i: A software package for control of device and data analysisMilestone 3a ii: Determination of hardware components needed for embedding software into device and displaying the user interface Deliverable 3b. Creation of Intuitive User Interface An intuitive user interface to run on a touch screen panel incorporated into the device will be developed. Plan 1. Determine the functionality of the user interface.2. Develop an intuitive and easy-to-use user interface. Milestone 3b: Implementation of a User Interface Work Package [4]. Operational Safety of Product Deliverable 4a. Safe-to-use CD consumable Overall user safety for the CD will be evaluated. Safe sample loading, preparation and disposal of the CD within the working environment will be addressed. Plan 1. Evaluate different methods for loading blood onto the disc. These may include different types of syringes and methods to interact with the disc such as Luer lock connectors.2. Evaluate and determine safe operational procedures for the disc. This will encompass the total use of the disc from preparation to disposal in ensuring that the disc is safe to use. Milestone 4a: Comprehensive information to be used in the design and manufacture of the microfluidic CD Deliverable 4b. Operational Safety of the Device Safety devices for the system will be thoroughly considered. Plan 1. Evaluate and determine the hardware components needed for safe operation of the device in the event of user/hardware error. These will include mechanical and software interlocks.2. Produce a safe operating procedure for the device. Milestone 4b: Collation of information and hardware to be used in the production of the prototype device Work Package [5]. A Working Prototype for Clinical use Deliverable 5a. Early end-user utility All the above stages will be combined into a single working prototype suitable for field trials. Plan 1. Laboratory tests of device on patient samples (see section 15 on ethics).2. Operational Handling of device by clinical staff. Milestone 5a: Early end-user results and feedback Deliverable 5b. Product refinement Feedback generated in 5a will allow refinements to be made to both software and hardware within the final working prototype. Plan 1. Alterations in accordance to feedback and performance.2. Demonstration to wider audiences of its potential as a device and as a system. Milestone 5b: Fine-tuned product ready for commercialisation Benefit Healthcare BenefitIntroduction of a POC device based upon this assay would be expected to have immediate effect upon patient survival by arming the clinician with the means to immediately distinguish potentially fatal sepsis from other sepsis-like conditions, or at a pre-symptomatic stage in the disease. It may be used subsequently to track the patient's recovery after therapy or to suggest alteration of treatment. Technical Innovation The assay has the following technical advantages:1. More accurate than other biomarkers (procalcitonin and C-reactive protein) for differentiating patients with severe sepsis and septic shock, showing 90% sensitivity and 92% negative predictive value [Crit Care Med 2008;36:1507, Crit Care Med 2006;34:1654],2. Uniquely effective in diagnosis of sepsis in cardiac surgery patients (was able to discriminate between sepsis and non-septic systemic inflammatory response syndrome (SIRS) groups with 100% sensitivity and 93% specificity when neither C-reactive protein nor PCT (BRAHMS Kryptor PCT test) had significant predictive value) [Crit Care 2009;13:R180],3. An effective diagnostic of bacterial sepsis in neutropenic oncology patients [Thromb Haemost 2008;100:146]. Healthcare InnovationLiverpool is well-placed to undertake and follow-through this work. The University of Liverpool has consolidated its strengths in Infection research with a new £90M building to house the Institute in Infection & Global Health. This will complement the clinical focus and translational research base at the Royal Liverpool University Hospital with its NIHR Biomedical Research Centre (BRC) in Microbial Disease and planned Bio-innovation Campus. Uniquely, Liverpool also has the School of Tropical Medicine that leverages access to trials in under-resourced settings where infection is the major global cause of death. Worldwide, sepsis affects 18 million people annually.


Research activity codes: 4.1 DISCOVERY AND PRECLINICAL TESTING OF MARKERS AND TECHNOLOGIES
Health categories: INFLAMMATORY AND IMMUNE SYSTEM;INFECTION