Fan Yuan

Overview:

Dr. Yuan's research interests include drug and gene delivery, mechanisms of molecular transport in cells and tissues, and tumor pathophysiology.

Cure of cancer through chemotherapy requires drug molecules to reach all tumor cells at an adequately high concentration. At present, such a requirement cannot be satisfied in most patients. This is because (a) amount of drugs that can be administered into patients is limited by normal tissue tolerance and (b) drug distribution and cellular response to drugs in tumors are heterogeneous. Therefore, cells in regions with drug concentration below the therapeutic level will cause tumor recurrence and they may also develop resistance to future treatment.

The goal of our research is two-fold. One is to improve delivery of therapeutic agents in solid tumors; and the second is to understand mechanisms of drug resistance in tumors caused by intrinsic cellular heterogeneity and physiological barriers. These studies may provide useful information on how to improve clinical treatment of cancer based on currently available drugs or molecular medicines in the future.

Research projects in our lab include quantification of transport parameters, delivery of drugs encapsulated in temperature sensitive liposomes, physical interventions of drugs, electric field-mediated gene delivery, mathematical modeling of drug and gene delivery.

Positions:

Professor of Biomedical Engineering

Biomedical Engineering
Pratt School of Engineering

Professor in Ophthalmology

Ophthalmology
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

B.S. 1983

Peking University (China)

M.S. 1985

Peking University (China)

Ph.D. 1990

City University of New York

Grants:

University Training Program in Biomolecular and Tissue Engineering

Administered By
Biomedical Engineering
Awarded By
National Institutes of Health
Role
Mentor
Start Date
End Date

University Training Program in Biomolecular and Tissue Engineering

Administered By
Biomedical Engineering
Awarded By
National Institutes of Health
Role
Mentor
Start Date
End Date

Intravital point-scanning confocal microscope

Administered By
Biomedical Engineering
Awarded By
National Institutes of Health
Role
Major User
Start Date
End Date

Upgrade of a Shared Instrumentation Resource in the PSOE: The Laser Scanning Confocal Microscope

Administered By
Biomedical Engineering
Awarded By
Lord Foundation of North Carolina
Role
Co-Principal Investigator
Start Date
End Date

Non-Canonical Pathways for Electrogene Transfer

Administered By
Biomedical Engineering
Awarded By
National Institutes of Health
Role
Principal Investigator
Start Date
End Date

Publications:

An Enhanced Tilted-Angle Acoustofluidic Chip for Cancer Cell Manipulation

In recent years, surface acoustic wave (SAW) devices have demonstrated great potentials and increasing applications in the manipulation of nano- and micro-particles including biological cells with the advantages of label-free, high sensitivity and accuracy. In this letter, we introduce a novel tilted-angle SAW devices to optimise the acoustic pressure inside a microchannel for cancer-cell manipulation. The SAW generation and acoustic radiation force are improved by seamlessly patterning electrodes in the space surrounding the microchannel. Comparisons between this novel SAW device and a conventional device show a 32% enhanced separation efficiency while the input power, manufacturing cost and fabrication effort remain the same. Effective separation of HeLa cancer cells from peripheral blood mononuclear cells is demonstrated. This novel SAW device has the advantages in minimizing device power consumption, lowering component footprint and increasing device density.
Authors
Wu, F; Shen, MH; Yang, J; Wang, H; Mikhaylov, R; Clayton, A; Qin, X; Sun, C; Xie, Z; Cai, M; Wei, J; Liang, D; Yuan, F; Wu, Z; Fu, Y; Yang, Z; Sun, X; Tian, L; Yang, X
MLA Citation
Wu, F., et al. “An Enhanced Tilted-Angle Acoustofluidic Chip for Cancer Cell Manipulation.” Ieee Electron Device Letters, vol. 42, no. 4, Apr. 2021, pp. 577–80. Scopus, doi:10.1109/LED.2021.3062292.
URI
https://scholars.duke.edu/individual/pub1477216
Source
scopus
Published In
Ieee Electron Device Letters
Volume
42
Published Date
Start Page
577
End Page
580
DOI
10.1109/LED.2021.3062292

A statistical framework for determination of minimal plasmid copy number required for transgene expression in mammalian cells.

Plasmid DNA (pDNA) has been widely used for non-viral gene delivery. After pDNA molecules enter a mammalian cell, they may be trapped in subcellular structures or degraded by nucleases. Only a fraction of them can function as templates for transcription in the nucleus. Thus, an important question is, what is the minimal amount of pDNA molecules that need to be delivered into a cell for transgene expression? At present, it is technically a challenge to experimentally answer the question. To this end, we developed a statistical framework to establish the relationship between two experimentally quantifiable factors - average copy number of pDNA per cell among a group of cells after transfection and percent of the cells with transgene expression. The framework was applied to the analysis of electrotransfection under different experimental conditions in vitro. We experimentally varied the average copy number per cell and the electrotransfection efficiency through changes in extracellular pDNA dose, electric field strength, and pulse number. The experimental data could be explained or predicted quantitatively by the statistical framework. Based on the data and the framework, we could predict that the minimal number of pDNA molecules in the nucleus for transgene expression was on the order of 10. Although the prediction was dependent on the cell and experimental conditions used in the study, the framework may be generally applied to analysis of non-viral gene delivery.
Authors
Wang, L; Chang, C-C; Sylvers, J; Yuan, F
MLA Citation
Wang, Liangli, et al. “A statistical framework for determination of minimal plasmid copy number required for transgene expression in mammalian cells.Bioelectrochemistry (Amsterdam, Netherlands), vol. 138, Apr. 2021, p. 107731. Epmc, doi:10.1016/j.bioelechem.2020.107731.
URI
https://scholars.duke.edu/individual/pub1470723
PMID
33434786
Source
epmc
Published In
Bioelectrochemistry (Amsterdam, Netherlands)
Volume
138
Published Date
Start Page
107731
DOI
10.1016/j.bioelechem.2020.107731

Thin film Gallium nitride (GaN) based acoustofluidic Tweezer: Modelling and microparticle manipulation.

Gallium nitride (GaN) is a compound semiconductor which shows advantages in new functionalities and applications due to its piezoelectric, optoelectronic, and piezo-resistive properties. This study develops a thin film GaN-based acoustic tweezer (GaNAT) using surface acoustic waves (SAWs) and demonstrates its acoustofluidic ability to pattern and manipulate microparticles. Although the piezoelectric performance of the GaNAT is compromised compared with conventional lithium niobate-based SAW devices, the inherited properties of GaN allow higher input powers and superior thermal stability. This study shows for the first time that thin film GaN is suitable for the fabrication of the acoustofluidic devices to manipulate microparticles with excellent performance. Numerical modelling of the acoustic pressure fields and the trajectories of mixtures of microparticles driven by the GaNAT was performed and the results were verified from the experimental studies using samples of polystyrene microspheres. The work has proved the robustness of thin film GaN as a candidate material to develop high-power acoustic tweezers, with the potential of monolithical integration with electronics to offer diverse microsystem applications.
Authors
Sun, C; Wu, F; Fu, Y; Wallis, DJ; Mikhaylov, R; Yuan, F; Liang, D; Xie, Z; Wang, H; Tao, R; Shen, MH; Yang, J; Xun, W; Wu, Z; Yang, Z; Cang, H; Yang, X
MLA Citation
Sun, Chao, et al. “Thin film Gallium nitride (GaN) based acoustofluidic Tweezer: Modelling and microparticle manipulation.Ultrasonics, vol. 108, Dec. 2020, p. 106202. Epmc, doi:10.1016/j.ultras.2020.106202.
URI
https://scholars.duke.edu/individual/pub1448356
PMID
32535411
Source
epmc
Published In
Ultrasonics
Volume
108
Published Date
Start Page
106202
DOI
10.1016/j.ultras.2020.106202

Inhibition of Caspases Improves Non-Viral T Cell Receptor Editing.

T cell receptor (TCR) knockout is a critical step in producing universal chimeric antigen receptor T cells for cancer immunotherapy. A promising approach to achieving the knockout is to deliver the CRISPR/Cas9 system into cells using electrotransfer technology. However, clinical applications of the technology are currently limited by the low cell viability. In this study, we attempt to solve the problem by screening small molecule drugs with an immortalized human T cell line, Jurkat clone E6-1, for inhibition of apoptosis. The study identifies a few caspase inhibitors that could be used to simultaneously enhance the cell viability and the efficiency of plasmid DNA electrotransfer. Additionally, we show that the enhancement could be achieved through knockdown of caspase 3 expression in siRNA treated cells, suggesting that the cell death in electrotransfer experiments was caused mainly by caspase 3-dependent apoptosis. Finally, we investigated if the caspase inhibitors could improve TCR gene-editing with electrotransferred ribonucleoprotein, a complex of Cas9 protein and a T cell receptor-α constant (TRAC)-targeting single guide RNA (sgRNA). Our data showed that inhibition of caspases post electrotransfer could significantly increase cell viability without compromising the TCR disruption efficiency. These new findings can be used to improve non-viral T cell engineering.
Authors
MLA Citation
Wang, Chunxi, et al. “Inhibition of Caspases Improves Non-Viral T Cell Receptor Editing.Cancers, vol. 12, no. 9, Sept. 2020. Epmc, doi:10.3390/cancers12092603.
URI
https://scholars.duke.edu/individual/pub1461009
PMID
32933048
Source
epmc
Published In
Cancers
Volume
12
Published Date
DOI
10.3390/cancers12092603

Enhancing Cell Viability and Efficiency of Plasmid DNA Electrotransfer Through Reducing Plasma Membrane Permeabilization.

<h4>Background</h4>Pulsed electric field has been widely used to facilitate molecular cargo transfer into cells. However, the cell viability is often decreased when trying to increase the electrotransfer efficiency. We hypothesize that the decrease is due to electropermeabilization of cell membrane that disrupts homeostasis of intracellular microenvironment. Thus, a reduction in the membrane permeabilization may increase the cell viability.<h4>Materials and methods</h4>Different compounds were supplemented into the pulsing buffer prior to electrotransfer for reduction of cell membrane damage. Extent of the damage was quantified by leakiness of the membrane to a fluorescent dye, calcein, preloaded into cells. At 24 hours post electrotransfer, cell viability and electrotransfer efficiency were quantified with flow cytometry.<h4>Results</h4>The cell viability could be substantially increased by supplementation of either type B gelatin or bovine serum albumin (BSA), without compromising the electrotransfer efficiency. The supplementation also decreased the amount of calcein leaking out of the cells, suggesting that the improvement in cell viability was due to the reduction in electrotransfer-induced membrane damage.<h4>Conclusion</h4>Data from the study demonstrate that type B gelatin and BSA can be used as inexpensive supplements for improving cell viability in electrotransfer.
Authors
Wang, Y; Chang, C-C; Wang, L; Yuan, F
MLA Citation
Wang, Yanhua, et al. “Enhancing Cell Viability and Efficiency of Plasmid DNA Electrotransfer Through Reducing Plasma Membrane Permeabilization.Bioelectricity, vol. 2, no. 3, Sept. 2020, pp. 251–57. Epmc, doi:10.1089/bioe.2020.0007.
URI
https://scholars.duke.edu/individual/pub1470031
PMID
33344914
Source
epmc
Published In
Bioelectricity
Volume
2
Published Date
Start Page
251
End Page
257
DOI
10.1089/bioe.2020.0007