A Novel GMP Protocol to Produce High-Quality Treg Cells From the Pediatric Thymic Tissue to Be Employed as Cellular Therapy
Open Access
- 16 May 2022
- journal article
- research article
- Published by Frontiers Media SA in Frontiers in Immunology
- Vol. 13, 893576
- https://doi.org/10.3389/fimmu.2022.893576
Abstract
Due to their suppressive capacity, the adoptive transfer of regulatory T cells (Treg) has acquired a growing interest in controlling exacerbated inflammatory responses. Limited Treg recovery and reduced quality remain the main obstacles in most current protocols where differentiated Treg are obtained from adult peripheral blood. An alternate Treg source is umbilical cord blood, a promising source of Treg cells due to the higher frequency of naïve Treg and lower frequency of memory T cells present in the fetus' blood. However, the Treg number isolated from cord blood remains limiting. Human thymuses routinely discarded during pediatric cardiac surgeries to access the retrosternal operative field has been recently proposed as a novel source of Treg for cellular therapy. This strategy overcomes the main limitations of current Treg sources, allowing the obtention of very high numbers of undifferentiated Treg. We have developed a novel good manufacturing practice (GMP) protocol to obtain large Treg amounts, with very high purity and suppressive capacity, from the pediatric thymus (named hereafter thyTreg). The total amount of thyTreg obtained at the end of the procedure, after a short-term culture of 7 days, reach an average approximately of 1,500 x106 cells from a single thymus. The thyTreg product obtained with our protocol shows very high viability (>95%), very high purity (>90% of CD25+FOXP3+ cells), stability under proinflammatory conditions and a very high suppressive capacity (inhibiting in more than 75% the proliferation of activated CD4+ and CD8+ T cells in vitro). Our thyTreg product has been approved by the Spanish Drug Agency (AEMPS) to be administered as cell therapy. We are recruiting patients in the first-in-human phase I/II clinical trial worldwide that evaluates the safety, feasibility, and efficacy of autologous thyTreg administration in children undergoing heart transplantation (NCT04924491). The high quality and amount of thyTreg and the differential features of the final product obtained with our protocol allow preparing hundreds of doses from a single thymus with improved therapeutic properties, which can be cryopreserved and could open the possibility of an "off-the-shelf" allogeneic use in another individual.Funding Information
- Instituto de Salud Carlos III (ICI20/00063, PI21/00189, PI18/00495, PI18/00506, CD18/00105)
- H2020 Excellent Science (MSCA-IF-EF-RI. 101028834)
- Comunidad de Madrid (B2017/BMD3727)
This publication has 56 references indexed in Scilit:
- Immunoselection and clinical use of T regulatory cells in HLA-haploidentical stem cell transplantationBest Practice & Research Clinical Haematology, 2011
- CXCR3 in T cell functionExperimental Cell Research, 2011
- Infusion of ex vivo expanded T regulatory cells in adults transplanted with umbilical cord blood: safety profile and detection kineticsBlood, 2011
- Human regulatory T cells in autoimmune diseasesCurrent Opinion in Immunology, 2010
- Functional Delineation and Differentiation Dynamics of Human CD4+ T Cells Expressing the FoxP3 Transcription FactorImmunity, 2009
- Human T Regulatory Cell Therapy: Take a Billion or So and Call Me in the MorningImmunity, 2009
- Mechanisms of regulatory T‐cell suppression – a diverse arsenal for a moving targetImmunology, 2008
- Comparative Study of Regulatory T Cell Function of HumanT Cells from Thymocytes, Cord Blood, and Adult Peripheral BloodJournal of Immunology Research, 2008
- Altering the distribution of Foxp3+ regulatory T cells results in tissue-specific inflammatory diseaseThe Journal of Experimental Medicine, 2007
- Human CD4+ CD25hi Foxp3+ regulatory T cells are derived by rapid turnover of memory populations in vivoJCI Insight, 2006