The proprietary concept is built upon the scientific premise that a disease evokes unique systemic responses in monocytes that can be accurately measured in the blood samples of patients.
Two-Step Platform Technology
The technology enables assessment of intracellular clearance of relevant biomarkers for specific neurodegenerative diseases through a two-step process consisting of the following two steps: Efficient isolation of blood monocytes (cell sorting) and) use of proprietary monoclonal antibodies to quantify the degradation of these biomarkers through an sensitive immunoassay test.
The use of monocytes as sample material, allows for higher concentration of the biomarker in the isolated blood sample. In combination with the ultra-sensitive digital immunoassay (Simoa, Quanterix) it enables development of assays providing much earlier disease detection, better prognoses, and enhanced treatment.
Blood Cell Isolation
The PreDx technology has been optimized using two different isolation methods, positive and negative isolation. Both methods can be performed manually or automated. For the negative isolation method, unwanted blood cells are removed by crosslinking to red blood cells (RBCs) present in the sample.
Target cells are purified during standard density gradient centrifugation, resulting in a pure monocyte sample. The positive isolation method uses antibodies selective for monocytes bound to paramagnetic beads. By placing the sample on a magnet, bead-bound monocytes are separated from the rest of the sample.
Before analysis, the cells are lysed, resulting in breakdown of the cell membranes and the cell content becomes available for analysis.
Pre Diagnostics uses a digital immunoassay (Simoa, Quanterix). Paramagnetic particles coupled with PreDx proprietary antibodies, designed to bind to the specific biomarker, are added to the sample. Subsequently, detection antibodies – capable of generating fluorescent product – are added. The objective is to form an immunocomplex consisting of the bead, bound protein, and detection antibody. At low concentrations, each bead will contain one bound protein, or none.
The sample is loaded into arrays, in the Simoa disc, consisting of more than 200,000 microwells – each large enough to hold one bead. The signal intensity on each bead is read and sample concentration determined from a calibration curve. To support future high-volume demand, the unique set of antibodies and reagents used in the digital immunoassay will be further optimized to ensure compatibility with the high-volume immunoassay instruments available in routine IVD laboratories.