One-step visualization of natural cell activities in non-labeled living spheroids
Abstract 3D cultured cell aggregates, including spheroids, reflect the gene expression patterns of living tissues/organs. Mass preparation of spheroids enables high-throughput drug screening (HTS). However, conventional optical imaging of spheroids makes it difficult to obtain sufficient resolution...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2022-01-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-022-05347-z |
| _version_ | 1818300288020250624 |
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| author | Shotaro Tanaka Kotaro Takizawa Fumio Nakamura |
| author_facet | Shotaro Tanaka Kotaro Takizawa Fumio Nakamura |
| author_sort | Shotaro Tanaka |
| collection | DOAJ |
| description | Abstract 3D cultured cell aggregates, including spheroids, reflect the gene expression patterns of living tissues/organs. Mass preparation of spheroids enables high-throughput drug screening (HTS). However, conventional optical imaging of spheroids makes it difficult to obtain sufficient resolution of individual living cells in the thick cellular stack. Rapid and accurate assessment of cellular responses in spheroids is required for effective drug screening. Here, we show that negative contrast imaging (NCI) of spheroids overcomes this issue. Hydrophilic fluorescent dye added into the culture medium rapidly diffused into the intercellular space of living spheroids within a few minutes. Confocal microscopy showed the NCI of individual cells as dark and detailed contours clearly separated with fluorescence signals in the intercellular space. NCI enables the visualization of the alteration of cell morphology after anti-tumor drug application to living spheroids and the measurement of the fluorescent dye diffusion rate without any complicated pretreatments. Using this system, we found that the antitumor drug doxorubicin reduced the intercellular space of spheroids consisting of the human hepatocyte carcinoma cell line HepG2, through the activation of TGF-β signaling and upregulation of ECM protein expression, implicating a drug resistance mechanism. Collectively, the combination of NCI of spheroids and HTS may enhance the efficiency of drug discovery. |
| first_indexed | 2024-12-13T05:04:44Z |
| format | Article |
| id | doaj.art-29e8ab50c9454904b3b2c868707067d5 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-13T05:04:44Z |
| publishDate | 2022-01-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-29e8ab50c9454904b3b2c868707067d52022-12-21T23:58:42ZengNature PortfolioScientific Reports2045-23222022-01-0112111110.1038/s41598-022-05347-zOne-step visualization of natural cell activities in non-labeled living spheroidsShotaro Tanaka0Kotaro Takizawa1Fumio Nakamura2Department of Biochemistry, Tokyo Women’s Medical University School of MedicineDepartment of Biochemistry, Tokyo Women’s Medical University School of MedicineDepartment of Biochemistry, Tokyo Women’s Medical University School of MedicineAbstract 3D cultured cell aggregates, including spheroids, reflect the gene expression patterns of living tissues/organs. Mass preparation of spheroids enables high-throughput drug screening (HTS). However, conventional optical imaging of spheroids makes it difficult to obtain sufficient resolution of individual living cells in the thick cellular stack. Rapid and accurate assessment of cellular responses in spheroids is required for effective drug screening. Here, we show that negative contrast imaging (NCI) of spheroids overcomes this issue. Hydrophilic fluorescent dye added into the culture medium rapidly diffused into the intercellular space of living spheroids within a few minutes. Confocal microscopy showed the NCI of individual cells as dark and detailed contours clearly separated with fluorescence signals in the intercellular space. NCI enables the visualization of the alteration of cell morphology after anti-tumor drug application to living spheroids and the measurement of the fluorescent dye diffusion rate without any complicated pretreatments. Using this system, we found that the antitumor drug doxorubicin reduced the intercellular space of spheroids consisting of the human hepatocyte carcinoma cell line HepG2, through the activation of TGF-β signaling and upregulation of ECM protein expression, implicating a drug resistance mechanism. Collectively, the combination of NCI of spheroids and HTS may enhance the efficiency of drug discovery.https://doi.org/10.1038/s41598-022-05347-z |
| spellingShingle | Shotaro Tanaka Kotaro Takizawa Fumio Nakamura One-step visualization of natural cell activities in non-labeled living spheroids Scientific Reports |
| title | One-step visualization of natural cell activities in non-labeled living spheroids |
| title_full | One-step visualization of natural cell activities in non-labeled living spheroids |
| title_fullStr | One-step visualization of natural cell activities in non-labeled living spheroids |
| title_full_unstemmed | One-step visualization of natural cell activities in non-labeled living spheroids |
| title_short | One-step visualization of natural cell activities in non-labeled living spheroids |
| title_sort | one step visualization of natural cell activities in non labeled living spheroids |
| url | https://doi.org/10.1038/s41598-022-05347-z |
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