The discovery of induced pluripotent stem cells (iPSCs) constitutes a paradigm shift in regenerative medicine and holds a promise for new therapies for numerous hard to treat conditions such as cancer, diabetes, myocardial injury, retinitis pigmentosa and neurodegenerative diseases. iPSCs can be turned into any type of cell in the body and can be produced from any person in an autologous manner which circumvents the risk for graft rejection. Our aim in this project is to significantly advance this concept by developing a technology enabling mass production of autologous iPSCs.

iPSCs have the potential of producing advanced therapeutic medicinal products (ATMPs) including CAR-T cells, pancreatic islets, cardiomyocytes, and neurons. In accordance, a wide array of clinical trials is underway to treat Parkinson’s disease, blindness and different immune disorders utilizing iPSCs or human embryonic stem cells (ESC) [1]. However, the use of human ESCs is ethically controversial and the problem that most clinical trials face relates to the life-long use of immunosuppressants which is required to prevent tissue rejection because the iPSCs and ESCs are derived from genetically unrelated donors (allogeneic) [2].

Potential solutions to the problem of iPSC immunogenicity include modifying (deleting, replacing, and overexpressing) immunological genes to shield or hide the cells from the immune system3,4 as well as production of banks of iPSCs that are predicted to match human histocompatibility antigens (HLA) that are common in specific populations [5]. However, both approaches have significant shortcomings and the concept of hypo-immunological evasion has serious safety concerns [6]. Allogeneic iPSC and ESC trials have already shown indications of immunological complications [7], putting further investments in this highly promising field of medicine in jeopardy. Due to these hurdles, stem cell therapies have not yet gained significant clinical momentum.

Summary of AiPSC objectives

Challenge 1: The current use of allogenic iPSC is incompatible with many recipients and therapies.

Even though the potential of iPSC-based therapies is phenomenal, most iPSC-based therapies under development use immunologically non-matched (allogenic) lines. Therefore, patients receive immunosuppression to prevent immune rejection [1]. With regard to the HLA-banking approach, recipients whose HLA profile does not match with the available iPSC lines will end up being excluded. This problem has been theoretically addressed by engineering iPSCs without immunological recognition [3, 4]. However, the roadmap for approval is long due to safety concerns6 and the therapeutic potential of hypo-immunogenic iPSCs is limited to certain cell types because critical cell types such as hematopoietic stem cells [8], tissue resident macrophages [9], and thymocytes [10] depend on HLAs to perform their normal function.

Challenge 2: To date, manufacturing of autologous iPSCs is cost-ineffective and time-consuming.

The generation of autologous iPSCs would solve the immunogenicity problem described in Challenge 1. However, manufacturing of iPSCs under clinical standards (cGMP) is a multistep process that includes clean room procedures and extensive quality control for sterility, cell identity, purity, pluripotency, differentiation potential and genomic aberrations. The need for designated, GMP-approved clean room facilities, the cost of raw materials, the need for well-trained, experienced staff members and extensive quality tests gives the generation of one iPSC-line a price tag of approximately 500,000 € [11]. Additionally, the extensive manual handling (> 20 handling steps), daily monitoring of the cells during reprogramming and establishment of stable iPSC lines is portrayed in the long production time of a minimum of 6 months. This renders manufacturing of autologous iPSC cost-prohibitive, time-ineffective and poorly
suited for personalized therapies.

Challenge 3: To date, GMP-compliant iPSC manufacturing processes are not standardized.

Variability in the success of iPSC manufacturing is high and largely depends on the subjective expertise of the stem cell scientists in selecting highest quality clones [12, 13]. Additionally, the quality standards of different GMP-compliant iPSC lines are highly variable [7, 14, 15]. The latter stems from the lack of clear minimum requirements for quality control of iPSC lines as well as lack of simple, reliable and universal quality control tests for pluripotency and differentiation potential and genetic variation of newly generated iPSCs.

AiPSC promises to tackle these challenges by generating an AI-powered microfluidics platform for rapid, cost-effective, standardized, and automated manufacturing of clinical grade autologous iPSCs.

References:

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  2. Petrus-Reurer, S. et al. Immunological considerations and challenges for regenerative cellular therapies. Commun. Biol. 4, 798 (2021).
  3. Deuse, T. et al. Hypoimmunogenic derivatives of induced pluripotent stem cells evade immune rejection in fully immunocompetent allogeneic
    recipients. Nat. Biotechnol. 37, 252–258 (2019).
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  12. Schlaeger, T. M. et al. A comparison of non-integrating reprogramming methods. Nat. Biotechnol. 33, 58–63 (2015).
  13. O’Shea, O., Steeg, R., Chapman, C., Mackintosh, P. & Stacey, G. N. Development and implementation of large-scale quality control for the
    European bank for induced Pluripotent Stem Cells. Stem Cell Res. 45, 101773 (2020).
  14. Schweitzer, J. S. et al. Personalized iPSC-Derived Dopamine Progenitor Cells for Parkinson’s Disease. N. Engl. J. Med. 382, 1926–1932 (2020).
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