Ngoc Nhi Lê

Deep tech venture capital, startup strategy, and academic research commercialization.

 

Work History:

Startup and commercialization strategy consulting. Venture capital with focus on deep tech startups and VC funds. Accelerator associate at the Wisconsin Alumni Research Foundation (WARF). Director at gener8tor. 

 

Education:

Materials Science PhD from the University of Wisconsin-Madison. Research focus on stem cell engineering and biomanufacturing. Undergraduate degrees in Biomedical Engineering and Materials Science & Engineering from Georgia Tech.

Personal:

Vietnamese-American. Born in Vietnam, raised in  Georgia, USA, and residing in Wisconsin, USA.

Proud daughter of entrepreneurs-turned-factory workers and immigrants to the USA!

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Publications and Patents

Patent No: US 10,183,079

WARF Technology Summary (WARF: P160179US01)

Full Patent in PDF Format

Abstract: Vascular endothelial growth factor VEGF-sequestering hydrogel microspheres that have been prepared to selectively bind VEGF from blood products are disclosed herein. In one particular embodiment, the microspheres bind VEGF as part of an intra-operative process such that the growth factor can be removed from the blood products before the products are used in a clinical procedure.

Filed: March 18, 2916

Date of Patent: January 22, 2019

Inventors: William Murphy, David Belair, Ngoc Nhi Le, Michael Toepke, Nicholas Impellitteri, Connie Chamberlain

Assignee: Wisconsin Alumni Research Foundation​

Covalently-immobilized hydrogel arrays in multi-well plates

Patent No: US 9,694,338

WARF Technology Summary (WARF: P140305US01)

Full Patent in PDF Format

Abstract: Hydrogel arrays, methods for preparing hydrogel arrays and methods for screening cell-substrate interactions using the hydrogel arrays are disclosed. Advantageously, the hydrogel arrays include individual hydrogel posts that are completely isolatable, allowing for systematic and independent control of the chemical composition and physical dimensions of each hydrogel post.

Filed: December 18, 2014

Date of Patent: July 4, 2017

Inventors: William Murphy, Ngoc Nhi Le

Assignee: Wisconsin Alumni Research Foundation​

Method for forming hydrogel arrays using surfaces with differential wettability

Patent No: US  10,195,313

WARF Technology Summary (WARF: P140097US01)

Full Patent in PDF Format

Abstract: Patterned hydrogel arrays and methods of preparing patterned hydrogel arrays are disclosed. Advantageously, the methods used to prepare the patterned hydrogel arrays allow for controlling individual hydrogel spot conditions such as hydrogel spot modulus, hydrogel spot ligand identity and hydrogel spot ligand density, which allows for preparing a wide range of hydrogel spots in a single array format. Patterned hydrogel arrays can also be formed to include hydrogel-free pools surrounded by hydrogel. Additionally, the patterned hydrogel arrays of the present disclosure support the culture of a range of cell types. The patterned hydrogel arrays offer the ability to rapidly screen substrate components for influencing cell attachment, spreading, proliferation, migration, and differentiation.

Filed: July 24, 2014

Date of Patent: February 5, 2019

Inventors: William L. Murphy, Ngoc Nhi Thi Le, Stefan Zorn, Michael P. Schwartz, Eric Huy Dang Nguyen

Assignee: Wisconsin Alumni Research Foundation​

Hydrogel compositions for use in cell expansion and differentiation

Patent No: US 9,683,213

Full Patent in PDF Format

Abstract: Hydrogel compositions and methods of using hydrogel compositions are disclosed. Advantageously, the hydrogel compositions offer the ability to promote cellular expansion and/or cellular differentiation of various cells.
 

Filed: April 10, 2015

Date of Patent: June 20, 2017

Inventors: William L. Murphy, Matthew Brian Parlato, James A Molenda, Ngoc Nhi Le

Assignee: Wisconsin Alumni Research Foundation​

Hydrogel compositions for use in promoting tubulogenesis

Patent No: US 9,688,957

Full Patent in PDF Format

Abstract: Hydrogel Compositions and methods of using hydrogel compositions are disclosed. Advantageously, the hydrogel compositions offer the ability to rapidly screen substrate components for influencing cell attachment, spreading, proliferation, migration, and differentiation. In particularly suitable embodiments, the hydrogel compositions of the present disclosure may be used to promote tubulogenesis of endothelial cells.

Filed: April 10, 2015

Date of Patent: June 27, 2017

Inventors: William L. Murphy, Ngoc Nhi Le, Michael P. Schwartz, Eric Huy Dang Nguyen, Stefan Zorn, Hamisha Ardalani, Matthew Zanotelli, Matthew Brian Parlato, David Gregory Belair, William T. Daly

Assignee: Wisconsin Alumni Research Foundation​

Hydrogel arrays formed via differential wettability patterning enable combinatorial screening of stem cell behavior

Acta Biomaterialia
Volume 34, 1 April 2016, Pages 93-103

Full Article

Here, we have developed a novel method for forming hydrogel arrays using surfaces patterned with differential wettability. Our method for benchtop array formation is suitable for enhanced-throughput, combinatorial screening of biochemical and biophysical cues from chemically defined cell culture substrates. We demonstrated the ability to generate these arrays without the need for liquid handling systems and screened the combinatorial effects of substrate stiffness and immobilized cell adhesion peptide concentration on human mesenchymal stem cell (hMSC) behavior during short-term 2-dimensional cell culture. Regardless of substrate stiffness, hMSC initial cell attachment, spreading, and proliferation were linearly correlated with immobilized CRGDS peptide concentration. Increasing substrate stiffness also resulted in increased hMSC initial cell attachment, spreading, and proliferation; however, examination of the combinatorial effects of CRGDS peptide concentration and substrate stiffness revealed potential interplay between these distinct substrate signals. Maximal hMSC proliferation seen on substrates with either high stiffness or high CRGDS peptide concentration suggests that some baseline level of cytoskeletal tension was required for hMSC proliferation on hydrogel substrates and that multiple substrate signals could be engineered to work in synergy to promote mechanosensing and regulate cell behavior.

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Biomaterial arrays with defined adhesion ligand densities and matrix stiffness identify distinct phenotypes for tumorigenic and non-tumorigenic human mesenchymal cell types

Biomaterials Science

Issue 5, 204, Pages 745-756

Full Article

Here, we aimed to investigate migration of a model tumor cell line (HT-1080 fibrosarcoma cells, HT-1080s) using synthetic biomaterials to systematically vary peptide ligand density and substrate stiffness. A range of substrate elastic moduli were investigated by using poly(ethylene glycol) (PEG) hydrogel arrays (0.34–17 kPa) and self-assembled monolayer (SAM) arrays (∼0.1–1 GPa), while cell adhesion was tuned by varying the presentation of Arg-Gly-Asp (RGD)-containing peptides. HT-1080 motility was insensitive to cell adhesion ligand density on RGD-SAMs, as they migrated with similar speed and directionality for a wide range of RGD densities (0.2–5% mol fraction RGD). Similarly, HT-1080 migration speed was weakly dependent on adhesion on 0.34 kPa PEG surfaces. On 13 kPa surfaces, a sharp initial increase in cell speed was observed at low RGD concentration, with no further changes observed as RGD concentration was increased further. An increase in cell speed ∼two-fold for the 13 kPa relative to the 0.34 kPa PEG surface suggested an important role for substrate stiffness in mediating motility, which was confirmed for HT-1080s migrating on variable modulus PEG hydrogels with constant RGD concentration. Notably, despite ∼two-fold changes in cell speed over a wide range of moduli, HT-1080s adopted rounded morphologies on all surfaces investigated, which contrasted with well spread primary human mesenchymal stem cells (hMSCs). Taken together, our results demonstrate that HT-1080s are morphologically distinct from primary mesenchymal cells (hMSCs) and migrate with minimal dependence on cell adhesion for surfaces within a wide range of moduli, whereas motility is strongly influenced by matrix mechanical properties.

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Design of growth factor sequestering biomaterials

Chemical Communications

Issue 99, 2014, Pages 15651-15668

Full Article

Growth factors (GFs) are major regulatory proteins that can govern cell fate, migration, and organization. Numerous aspects of the cell milieu can modulate cell responses to GFs, and GF regulation is often achieved by the native extracellular matrix (ECM). For example, the ECM can sequester GFs and thereby control GF bioavailability. In addition, GFs can exert distinct effects depending on whether they are sequestered in solution, at two-dimensional interfaces, or within three-dimensional matrices. Understanding how the context of GF sequestering impacts cell function in the native ECM can instruct the design of soluble or insoluble GF sequestering moieties, which can then be used in a variety of bioengineering applications. This Feature Article provides an overview of the natural mechanisms of GF sequestering in the cell milieu, and reviews the recent bioengineering approaches that have sequestered GFs to modulate cell function. Results to date demonstrate that the cell response to GF sequestering depends on the affinity of the sequestering interaction, the spatial proximity of sequestering in relation to cells, the source of the GF (supplemented or endogenous), and the phase of the sequestering moiety (soluble or insoluble). We highlight the importance of context for the future design of biomaterials that can leverage endogenous molecules in the cell milieu and mitigate the need for supplemented factors.

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Versatile synthetic alternatives to Matrigel for vascular toxicity screening and stem cell expansion

Nature Biomedical Engineering

Volume 1, Article number: 0096 (2017)

Full Article

The physiological relevance of Matrigel as a cell-culture substrate and in angiogenesis assays is often called into question. Here, we describe an array-based method for the identification of synthetic hydrogels that promote the formation of robust in vitro vascular networks for the detection of putative vascular disruptors and that support human embryonic stem cell expansion and pluripotency. We identified hydrogel substrates that promote endothelial-network formation by primary human umbilical vein endothelial cells and by endothelial cells derived from human-induced pluripotent stem cells, and used the hydrogels with endothelial networks to identify angiogenesis inhibitors. The synthetic hydrogels showed superior sensitivity and reproducibility over Matrigel when known inhibitors were evaluated, as well as in a blinded screen of a subset of 38 chemicals, selected according to predicted vascular disruption potential, from the Toxicity ForeCaster library of the United States Environmental Protection Agency. We propose that the identified synthetic hydrogels are suitable alternatives to Matrigel for common cell-culture applications.

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A chemically-defined screening platform reveals behavioral
similarities between primary human mesenchymal stem cells
and endothelial cells

Integrative Biology

Volume 4, Issue 12, December 2012, Pages 1508–1521

Full Article

Chemically defined substrates, which rigorously control protein–surface and cell–surface interactions, can be used to probe the effects of specific biomolecules on cell behavior. Here we combined a chemically-defined, array-based format with automated, time-lapse microscopy to efficiently screen cell–substrate interactions. Self-assembled monolayers (SAMs) of alkanethiolates bearing oligo(ethylene glycol) units and reactive terminal groups were used to present cell adhesion peptides while minimizing non-specific protein interactions. Specifically, we describe rapid fabrication of arrays of 1 mm spots, which present varied densities of the integrin-binding ligand Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP). Results indicate that cell attachment, cell spreading, and proliferation exhibit strong dependencies on GRGDSP density for both human mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs). Furthermore, relative spreading and proliferation over a broad range of GRGDSP densities were similar for both primary cell types, and detailed comparison between cell behaviors identified a 1 : 1 correlation between spreading and proliferation for both HUVECs and hMSCs. Finally, time-lapse microscopy of SAM arrays revealed distinct adhesion-dependent migratory behaviors for HUVECs and hMSCs. These results demonstrate the benefits of using an array-based screening platform for investigating cell function. While the proof-of-concept focuses on simple cellular properties, the quantitative similarities observed for hMSCs and HUVECs provides a direct example of how phenomena that would not easily be predicted can be shown to correlate between different cell types.

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Regulating VEGF signaling in platelet concentrates via specific VEGF sequestering

Biomaterials Science

Issue 5, 2916

Full Article

Growth factors (GFs) are major regulatory proteins that can govern cell fate, Platelets contain an abundance of growth factors that mimic the composition of the wound healing milieu, and platelet-derived VEGF in particular can negatively influence wound healing if unregulated. Here, we sought to capture and regulate the activity of VEGF factor from human platelets using poly(ethylene glycol) microspheres. In this communication, we demonstrate that platelet freeze/thaw produced significantly higher levels of Vascular Endothelial Growth Factor (VEGF) than either calcium chloride treatment, protease activated receptor 1 activating peptide (PAR1AP) treatment, or thrombin treatment. PEG microspheres containing a VEGF-binding peptide (VBP), derived from VEGFR2, sequestered VEGF from platelet concentrate, prepared via freeze/thaw, and reduced the bioactivity of platelet concentrate in HUVEC culture, which suggests that VBP microspheres sequestered and reduced the activity of VEGF from patient-derived platelets. Here, we demonstrate the ability of VEGF sequestering microspheres to regulate the activity of VEGF derived from a growth factor-rich autologous human blood product.

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