We present a new technology platform, a hyperpolarized micromagnetic resonance spectrometer (HMRS), that achieves real-time, 103-fold more sensitive metabolic analysis on live cells
June 20, 2021
We present a new technology platform, a hyperpolarized micromagnetic resonance spectrometer (HMRS), that achieves real-time, 103-fold more sensitive metabolic analysis on live cells. concentration after the imatinib treatment. fig. S11. High-throughput analysis of hyperpolarized pyruvate. fig. S12. Comparison of the HMRS technique with conventional approaches to study metabolism. Abstract Metabolic reprogramming is usually widely considered a hallmark of cancer, and understanding metabolic dynamics described by the conversion rates or fluxes of metabolites can shed light onto biological processes of tumorigenesis and response to therapy. For real-time analysis of metabolic flux in intact cells or organisms, magnetic resonance (MR) Vicagrel spectroscopy and imaging methods have been developed in conjunction with hyperpolarization of nuclear spins. These approaches enable noninvasive monitoring of tumor progression and treatment efficacy and are being tested in multiple clinical trials. However, because of their limited Vicagrel sensitivity, these methods require a larger number of cells, around the order of 107, which is usually impractical for analyzing scant target cells or mass-limited samples. We present a new technology platform, a hyperpolarized micromagnetic resonance spectrometer (HMRS), that achieves real-time, 103-fold more sensitive metabolic analysis on live cells. This platform enables quantification of the metabolic flux in a wide range of cell types, including leukemia stem cells, without significant changes in viability, which allows downstream molecular analyses in tandem. It also enables rapid assessment of metabolic changes by a given drug, which may direct therapeutic choices in patients. We further advanced this platform for high-throughput analysis of hyperpolarized molecules by integrating a three-dimensionally printed microfluidic system. The HMRS platform holds promise as a sensitive method for studying metabolic dynamics in mass-limited samples, including primary malignancy cells, providing novel therapeutic targets and an enhanced understanding of cellular metabolism. value = not significant; Fig. 3D and fig. S6), demonstrating another advantage of the HMRS platform: nondestructive analysis of metabolic flux. Quantification of metabolic flux in LSCs LSCs, defined by their ability to initiate and re-establish malignancy upon transplantation, are more resistant to conventional therapeutic regimens as compared to bulk leukemia populations (oncogene are of particular interest because is related to deregulated expression of Myc (AML mice, were sorted on the basis of the surface protein c-Kit (CD117) and assayed rapidly within 24 hours noninvasively (Fig. 4, A and B) (AML. The leukemia cells, collected from a mouse bone marrow, were sorted using the gates indicated in the plot. (B) Median fluorescence intensity of c-Kit in the LSCs (c-KitHi) and leukemia nonCstem cells (c-KitLo) after 20 hours in media. MFI, mean fluorescence intensity. *= 0.0281. (C) Profiling of the flux metric in the leukemia cells. **= 0.0045. Rapid quantitative assessment of drug treatment response Because metabolic changes can be induced by anticancer drug treatments before major clinicopathological changes occur (transformed leukemic cells, were crushed in a sterile mortar in the addition of serum-free RPMI 1640 medium. The bone marrow leukemic cells were strained (70 M Nylon strainer, Falcon), resuspended in red blood cell lysis buffer (Qiagen) to remove red blood cells, and washed with serum-free RPMI 1640 media. After centrifugation (15,000 rpm, 5 min), the cell pellet was resuspended in 2% FBS/RPMI medium and stained with Mac1-PacBlue and c-KitCPeCy7 (myeloid leukemia stem cells employs a transcriptional program shared with embryonic rather than adult stem cells. Cell Stem Cell 4, 129C140 (2009). [PMC free article] [PubMed] [Google Scholar] 34. Park S.-M., G?nen M., Vu L., Minuesa G., Tivnan P., Barlowe T. S., Taggart J., Lu Y., Deering Vicagrel R. P., Hacohen N., Figueroa M. E., Paietta E., Fernandez H. F., Tallman M. S., Melnick A., Levine R., Leslie C., Lengner C. J., Kharas M. G., Musashi2 sustains the mixed-lineage leukemiaCdriven stem cell regulatory program. J. Clin. Invest. 125, 1286C1298 (2015). [PMC free article] [PubMed] [Google Scholar] 35. Stine Z. E., Vicagrel Walton Z. E., Altman B. J., Hsieh A. L., Dang C. V., MYC, metabolism, and cancer. Malignancy Discov. 5, 1024C1039 (2015). [PMC free article] [PubMed] [Google Scholar] 36. Krivtsov A. V., Twomey D., Feng Z., Stubbs M. C., Wang Y., Faber J., Levine J. FLI1 E., Wang J., Hahn W. C., Gary Gilliland D., Golub T. R., Armstrong S. A., Transformation Vicagrel from committed progenitor to leukaemia stem cell initiated by MLL-AF9. Nature 442, 818C822 (2006). [PubMed].