InVitroMetrix QCM-Based Cell Biosensor: Research tool to accelerate pharmaceutical drug discovery success

As part of the mini-symposium entitled Shark Tank-UMass Spin-out Life Sciences Start-ups, Dr. Dewilde discusses an example of UMass life sciences technology that has been spun out into a start-up company -- Cell QCM from UMass Lowell

InVitro-Q: A High-throughput Biosensor Used to Evaluate the Mechanism of Phagocytosis of Macrophages Using Different Particles

The method of phagocytosis of a particle can provide information on how macrophages respond to a detected particle. The response elicited varies based on the nature of the particle and in turn changes which receptor-mediated phagocytosis is initiated. We have developed a multi-well cell-based sensor that can monitor real-time biological changes in living cells, such as mass redistribution, and viscoelasticity. This system provides unique kinetic information regarding the phenotypic change in the cells post treatment. As a proof of principle study, we evaluate macrophage phagocytosis using three different particles: latex beads, Zymosan A, and Staphylococcus aureus. These studies show the InVitro-Q’s ability to distinguish and differentiate the unique physiological method of macrophage phagocytosis of an indigestible particle (latex beads), and digestible particles of different origins (Zymosan A (yeast cell wall) and S. aureus (wood bacteria). The real-time data generated illustrates the unique phenotypic signatures of macrophages in response to particle specific phagocytosis. The traces then dictate time points at which visualization will occur, and guides the elucidation of the mechanism of action

Companion Diagnostics for Breast Cancer Chemotherapeutics

Chemotherapy plays a major role in breast cancer treatment. However, not every chemotherapeutics is appropriate for each cancer due to the person’s individual cancer characteristics and whether the patient has developed chemoresistance to a particular drug. In this research, the InVitro-Q is used to detect subtle differences in tumor cell proliferation post-treatment with four-breast cancer chemotherapeutics used: paclitaxel, docetaxel, nocodazole, and cytochalasin B. Our multi-well cell-based sensor that can monitor real-time biological changes in living cells, such as mass redistribution, and viscoelasticity. This system provides unique kinetic information regarding the phenotypic change in the cells post treatment. Each drug induces apoptosis by targeting a different mechanism of action. Each drug was assayed for 48h with MCF-7 or SK-Br-3 breast cancer cells, and data collected. Post analysis we created quantitative projection regarding the efficacy of each drug on the specific cancer type

A living cell quartz crystal microbalance biosensor for continuous monitoring of cytotoxic responses of macrophages to single-walled carbon nanotubes

<p>Abstract</p> <p>Background</p> <p>Numerous engineered nanomaterials (ENMs) exist and new ENMs are being developed. A challenge to nanotoxicology and environmental health and safety is evaluating toxicity of ENMs before they become widely utilized. Cellular assays remain the predominant test platform yet these methods are limited by using discrete time endpoints and reliance on organic dyes, vulnerable to interference from ENMs. Label-free, continuous, rapid response systems with biologically meaningful endpoints are needed. We have developed a device to detect and monitor in real time responses of living cells to ENMs. The device, a living cell quartz crystal microbalance biosensor (QCMB), uses macrophages adherent to a quartz crystal. The communal response of macrophages to treatments is monitored continuously as changes in crystal oscillation frequency (Δf). We report the ability of this QCMB to distinguish benign from toxic exposures and reveal unique kinetic information about cellular responses to varying doses of single-walled carbon nanotubes (SWCNTs).</p> <p>Results</p> <p>We analyzed macrophage responses to additions of Zymosan A, polystyrene beads (PBs) (benign substances) or SWCNT (3-150 μg/ml) in the QCMB over 18 hrs. In parallel, toxicity was monitored over 24/48 hrs using conventional viability assays and histological stains to detect apoptosis. In the QCMB, a stable unchanging oscillation frequency occurred when cells alone, Zymosan A alone, PBs alone or SWCNTs without cells at the highest dose alone were used. With living cells in the QCMB, when Zymosan A, PBs or SWCNTs were added, a significant decrease in frequency occurred from 1-6 hrs. For SWCNTs, this Δf was dose-dependent. From 6-18 hrs, benign substances or low dose SWCNT (3-30 μg/ml) treatments showed a reversal of the decrease of oscillation frequency, returning to or exceeding pre-treatment levels. Cell recovery was confirmed in conventional assays. The lag time to see the Δf reversal in QCMB plots was linearly SWCNT-dose dependent. Lastly, the frequency never reversed at high dose SWCNT (100-150 μg/ml), and apoptosis/necrosis was documented in conventional 24 and 48 hr-assays.</p> <p>Conclusion</p> <p>These data suggest that the new QCMB detects and provides unique information about peak, sub-lethal and toxic exposures of living cells to ENMs before they are detected using conventional cell assays.</p