Alvin Stern, PhD

Managing Partner


Alvin Stern, has 35 years of experience purifying proteins.  His post-doctoral fellowship centered on new technologies for the purification of proteins at the Roche Institute of Molecular Biology in the laboratory of Sidney Udenfriend.  Dr. Stern is most well-known for his pioneering work at Hoffmann-La Roche Inc. on the purification of Interleukin-2 (IL-2) using this technology. During Dr. Stern’s career, he developed unique approaches to purify difficult proteins.  Some of these technologies were subsequently used in the purification of IL-1 and the IL-1 receptor.  Equally novel was the purification of natural IL-12 which opened a whole field in the study of the differentiation of naive T cells into Th0 cells, which further develop into either Th1 cells or Th2 cells.  Along with Dr. Ueli Gubler, he was awarded the Roche Research and Development Award for the discovery of Interleukin-12.  

Dr. Stern was head of the Protein Biochemistry group at Roche and thus contributed to all the Therapeutic Areas in Roche’s Discovery Research division with particular focus on purification and characterization of recombinant proteins for assay development and structural determination.  In his role at Roche, his responsibilities included outsourcing tasks utilizing both off-shore and US-based CROs, coordinating the projects, reviewing results and guiding experiments. These relationships were quite productive and Dr. Stern gained an appreciation of the value of utilizing the expertise of CROs.  However, during these interactions he also realized the drawbacks in existing CROs.

Dr. Stern is world renowned in his skill as a protein purifier. He is the author or coauthor of over 65 publications and the inventor or co-inventor on four protein purification patents.

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Ueli Gubler, PhD

Head, Biotechnology


Ueli Gubler has over 30 years of experience in the field of gene cloning, expression of proteins and general molecular biology techniques. While working at Hoffmann-La Roche, one of Dr. Gubler’s seminal contribution to the field was the development of a simple and highly efficient method for cDNA cloning. At Roche, this technique was applied in a number of projects, resulting in original reports of the cDNA-sequences and expression of growth hormone releasing factor (GRF), preprocholecystokinin (CCK), mouse interleukin-1 alpha and human interleukin-12. The cDNA cloning method was highly cited and the paper became a citation classic.   Along with Alvin Stern, he was awarded the Roche Research and Development Award for the discovery of Interleukin-12.

From 2007 to 2012, he has led a biotechnology group (cloning/sequencing, cell culture, protein purification) within a larger framework of highly interactive research and discovery teams. The primary function of this group was the preparation of recombinant proteins and cell lines as screening and assay reagents.

For the past 15 years, Dr. Gubler has been interested in finding ways to improve expression in mammalian cells via expression vector development.  One outcome of these efforts was the development of a mammalian cell line stably expressing high levels of the hERG channel, through the application and further reduction to practice of an existing site-specific recombination system. This cell line greatly simplified the standard testing of compounds in the LO phase for hERG activity and has been patented. Ueli also is a co-inventor on six other issued US patents, and is an author on 79 publications.

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Kuo-Sen Huang, PhD

Head, Assay Development and Screening

Kuo-Sen Huang has over 30 years of experience in protein biochemistry, assay development, high throughput screening and data management.  He joined Hoffmann La-Roche 25 years ago in the Department of Protein Biochemistry.  One of his first projects focused on the purification of a novel GPI specific phospholipase D from serum, which led to the discovery of its function.  Later, he and coworkers initiated a cell adhesion molecule project, studied site-specific mutagenesis of E-selectin and purified mutant proteins for crystal structure studies.  He developed a novel SPA assay for screening E-selectin antagonists.  He then purified several other cell adhesion molecules (e.g. VCAM-1, MAdCAM-1, VLA-4 and a4ß7 integrins) and developed assays for screening antagonists.  He worked closely with chemists and biologists on these projects and eventually developed a potent VLA4 antagonist for Phase I and II clinical studies. 

In 1999, he joined the High-Throughput Screening (HTS) Group in the Department of Discovery Technologies.  He was responsible for assay development, HTS and supporting lead discovery programs for Oncology, Metabolic Disease and Inflammation Department projects.  Through the course of the next 14 years, he led a group of scientists supporting more than 80 projects and made numerous contributions.  He developed novel assay technologies, optimized HTS process and streamlined data management.  His efforts shortened HTS timelines and reduced reagent costs by over 50%.  He also implemented several biophysical techniques for hit validation (e.g. Biacore, thermal shift assay and ITC) allowing chemist to focus on relevant compounds.  In addition to primary assays, his group was also responsible for developing secondary and selectivity assays for drug development.      

Prior to joining Roche, Dr. Huang was a protein biochemist at Biogen. He was responsible for purification of both small-scale and large-scale therapeutically interested proteins.  He did his postdoctoral work at M.I.T. studying bacteriorhodopsin in the laboratory of Nobel Laureate Dr. H. Gobind Khorana.  He is a trained enzymologist earning his Ph.D. at the University of Chicago.   He is an author of 45 publications and an inventor/co-inventor of five assay and protein related patents. 

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Naoko Tanaka, PhD

Head, Protein Biochemistry

Naoko Tanaka has been at the forefront of research on protein biochemistry and enzymology with over 14 years of international research experience in industrial and academic settings. At Hoffmann-La Roche, Naoko held a joint position between the Protein Biochemistry group in Discovery Technologies and the Biochemistry group in Department of Virology, where she focused on the purification and characterization of viral proteins and host interacting proteins for assay development and structure determination.

Prior to her experience at Roche, Dr. Tanaka had worked at premier research institutions such as Memorial Sloan-Kettering Cancer Center (New York), Cancer Research UK (Herts, UK) and Weill Medical College of Cornell University (New York). During her postdoctoral training, she made a demonstrable impact on the field of protein biochemistry with her research on RNA splicing and processing. Dr. Tanaka contributed to the advanced understanding of RNA splicing and its mechanism that is critical to the understanding of the cause of diseases with genetic disorders. All of her research publications, including 13 papers as a first author, contain exquisite biochemical data with complementing genetic assays or structural information, all the result of high quality protein/enzyme production.

Dr. Tanaka obtained her Ph.D degree in Biochemistry/Biocatalysis from University of Amsterdam (The Netherlands). As a native of Japan, her unique research experience in Europe and the U.S. has brought interesting cultural exchange among colleagues with whom she worked with. She also continues to make monumental contributions in the global healthcare research field in the collaborative manner in which she works.

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Wei Chu, PhD

Head, Molecular Biology

Wei Chu has more than 20 years of experience in biomedical research and development.  During his post-doctoral fellowship in the Department of Molecular Genetics at Hoffmann-La Roche, Dr. Chu identified and characterized multiple novel cytokine inducible genes in human endothelial cells and identified the mechanism of tissue-specific gene regulation of adhesion molecule, E-selectin.  Dr. Chu continued his career at Roche broadening his drug discovery knowledge base while being a member of several departments including Inflammation, Genomic Research, Biopharmaceuticals and Discovery Technologies.  The general theme throughout his career has been a focus on recombinant protein expression and vector engineering.

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William Windsor, PhD

Head, Physical Biochemistry

William Windsor has over 30 years of experience in preclinical drug discovery and is an expert in biochemical and biophysical analysis of protein-ligand / protein-protein interactions, enzymology and structure-based drug design used to elucidate the mechanism of action of small molecule inhibitors. Prior to joining Cepter Biopartners, Dr Windsor was the Director of the Biochemistry & Biophysics Department at the Merck Research Laboratory and Director of Kinase Research at Schering-Plough Research Institute (SPRIDr). Dr Windsor has extensive experience in methods of calorimetry (ITC, DSC), circular dichroism, absorbance and fluorescence spectroscopy and protein purification.  Among his accomplishments are the development of seven clinical drugs including: Sarasar (FPT inhibitor for Progeria and Oncology), HCV protease inhibitor Boceprevir, kinase inhibitors Dinaciclib (CDK2) and ERK inhibitor SCH 900353.  Dr. Windsor was awarded the Schering-Plough Presidential Research Award for the discovery of Dinaciclib and for the X-ray Structure of FPT and is an author and co-inventor for over 50 publications and patents.

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Lena Liang

Senior Scientist, Protein Biochemistry

Lena has extensive skills in protein biochemistry, with over 10 years of experience in field. Lena was a Senior Associate and Project Coordinator at Hoffmann-La Roche, where she was responsible for developing and executing protocols for protein production and protein characterization for the therapeutic areas. As Project Coordinator, she facilitated interdepartmental communication and collaborations with Project Managers.

Prior to joining Roche, Lena worked in Dinshaw Patel’s Lab at Memorial Sloan Kettering where she was involved in elucidating epigenetic regulation using protein crystallography.

Lena received her B.A. in biochemistry from New York University.

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Chenguang Zhao, PhD

Senior Scientist, Protein Biochemistry

Chenguang Zhao has more than 15 years of experience in protein expression, purification and biochemical characterization, specializing in membrane proteins. Prior to joining Cepter Biopartners, he was a research scientist at Yale University.  While there, he and his mentor, Dr. Christian Schlieker, discovered the regulatory mechanism of cofactors on Torsin ATPases and defined the molecular defect underlying DYT1 dystonia.  They also established Lamin B receptor mutants as model substrates for studying nuclear protein quality control, a poorly understood area of cellular protein homeostasis.  Dr. Zhao obtained his PhD degree in biochemistry from Goethe University Frankfurt in the group of Dr. Robert Tampè.  During his graduate research, he functionally reconstituted the human ABC Transporter Associated with Antigen Process (ABCB9) onto proteo-liposomes, a milestone on research in eukaryotic ABC transporters including multidrug resistance transporters.

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Yingsi Chen

Senior Scientist, Assay Development and Screening

Yingsi Chen has over 10 years of drug discovery experience.  At Hoffmann-La Roche she focused on lead optimization of drug candidates and high-throughput screening (HTS).  She supported multiple discovery projects in the therapeutic areas of oncology, metabolic diseases, inflammation and virology. Her technical expertise is in development of biochemical assays of a variety of assay formats including ELISA, HTRF, FP, absorbance, and fluorescence. She developed and conducted biochemical assays to support lead optimization of over 20 discovery projects, including assay support for an advanced cyclin dependent kinase (CDK) Inhibitor project from lead series identified to clinical candidate selected.  She was awarded a Roche Special Recognition Award in 2011 for her outstanding contribution to an inflammation project from assay development, HTS through lead series identification.

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Frank Podlaski

Senior Scientist, Physical Biochemistry

Frank Podlaski has experience in academia and industry including six years at Memorial Sloan Kettering Cancer Center and 30 years with Hoffmann-La Roche. In his last ten years at Roche, his role was as site expert for biosensor (BiaCore) label free assays for small molecule drug discovery.  Frank’s management of this function was pivotal in developing methods and processes to efficiently work multiple programs supporting three therapeutic areas including oncology, inflammation and metabolic diseases.  He produced binding data on over 20 targets for both enzyme and protein-protein interaction systems including kinases, and cytokines.  Prior to the role as biophysical scientist, he functioned as biochemist and developed expertise in immunochemistry, protein purification and characterization of recombinant and natural proteins. This early work focused on cytokine research with structure-function studies of IL-2 and IL-2 receptor including development of anti-peptide antibodies and epitope mapping. Concurrently working on discovery programs for new cytokines, he was an integral part of the team that discovered IL-12.  Frank is author/coauthor on 26 publications and has one purification patent.

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