Cardiopoietic cell therapy significantly improved left ventricular function, blunted pathological remodeling, and functional outcomes in animal models and Phase I/II clinical trial of heart failure patients. There is ongoing Phase III trial. In this therapeutic approach, bone marrow-derived mesenchymal stem cells are engaged into cardiac stem cells by exposing to a cardiogenic cocktail of growth factors, including activin A, transforming growth factor-b1, and bone morphogenetic protein-4, which is the single largest cost component of clinical manufacturing. These cytokines all belong to the TGF-b superfamily, which are critical for cardiopoietic stem cell expansion and differentiation. However, due to the complex post-proteolytic modifications and poor solubility at neutral pH, yield from all the curren manufacturing process is very low, and as a result bulk volume is uneconomical and not readily available. Currently, commercial products are transiently produced in non-human cell systems (E coli, SF9, CHO, by, for example, R&D Systems and PeproTech) or HEK293 cells (by, for example, HumanZyme and StemR&D) as research-use only reagents. Today, there is no capacity anywhere in the world to produce these essential TGF-b superfamily cytokines at the scale and quality that will meet the requirements for future large-scale clinical ex vivo processing of cardiopoietic and other human stem cell products. Currently, these high-demand cytokines are costly, $6540-$9,800/mg, which severely hinders clinical scale processing of stem cell therapeutics. We have been focused on the development of a cost-effective and scalable expression system to produce authentic, recombinant TGF-b superfamily cytokines from stable HEK293SH cells that current human cell or non-human cell expression systems either cannot produce or cannot economically produce. The proprietary technology includes HEK293SH, a selected high-yield HEK293 cell line adapted to suspension for growth in serum-free and chemically defined medium, an optimized human promoter and signal peptide, optimization of post-translational processing, and proprietary purification and stabilization methods for these poor-solubility proteins. Currently, Activin A, TGFb1 and BMP4 are produced at >10-30 fold higher yield and exhibit greater stability, higher activity, and higher purity than any other products commercially available, resulting in profoundly lower raw material and process labor costs. In this study, we propose to further optimize the production and develop large-scale and cost-effective production and processing capabilities for generating serum-free and xeno-free TGFb superfamily cytokines, which will enable safe, robust, and cost-effective ex vivo processing of cardiopoietic mesenchymal stem cell therapeutics. The targeted price will be reduced from current $6540-$9,800/mg to $100/mg.

Public Health Relevance

We will optimize the production of serum-free and xeno-free growth factors to enable safe, robust, and cost-effective ex vivo processing of cardiopoietic mesenchymal stem cell therapeutics for heart failure patients.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Small Business Innovation Research Grants (SBIR) - Phase I (R43)
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Special Emphasis Panel (ZRG1-CVRS-C (10))
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Lee, Albert
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Apt Therapeutics, Inc.
Saint Louis
United States
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