A Novel GMP Protocol to Produce High-Quality Treg Cells From the Pediatric Thymic Tissue to Be Employed as Cellular Therapy

Pathological diagnosis and immunohistochemical analysis of giant retrosternal goiter in the elderly: A case report

BACKGROUND

Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition, often presenting clinical symptoms that can be confused with other diseases, posing diagnostic and therapeutic challenges. This study aims to delve into the characteristics and potential mechanisms of this ailment through pathological diagnosis and immunohistochemical analysis, providing clinicians with more precise diagnostic and treatment strategies.

CASE SUMMARY

A 77-year-old male, was admitted to hospital with the chief complaint of finding a goiter in the semilunar month during physical examination, accompanied by dyspnea. Locally protruding into the superior mediastinum, the adjacent structure was compressed, the trachea was compressed to the right, and the local lumen was slightly narrowed. The patient was diagnosed with giant retrosternal goiter. Considering dyspnea caused by trachea compression, our department planned to perform giant retrosternal thyroidectomy. Immunohistochemical results: Tg (+), TTF-1 (+), Calcitonin (CT) (I), Ki-67 (+, about 20%), CD34 (-). Retrosternal goiter means that more than 50% of the volume of the thyroid gland is below the upper margin of the sternum. As retrosternal goiter disease is a relatively rare disease, once the disease is diagnosed, it should be timely surgical treatment, and the treatment is more difficult, the need for professional medical team for comprehensive treatment.

CONCLUSION

The imaging manifestations of giant retrosternal goiter are atypical, histomorphology and immunohistochemistry can assist in its diagnosis. This article reviews the relevant literature of giant retrosternal goiter immunohistochemistry and shows that giant retrosternal goiter is positive for Tg, TTF-1, and Ki-67.

Treg in inborn errors of immunity: gaps, knowns and future perspectives

Regulatory T cells (Treg) are essential for immune balance, preventing overreactive responses and autoimmunity. Although traditionally characterized as CD4+CD25+CD127lowFoxP3hi, recent research has revealed diverse Treg subsets such as Tr1, Tr1-like, and CD8 Treg. Treg dysfunction leads to severe autoimmune diseases and immune-mediated inflammatory disorders. Inborn errors of immunity (IEI) are a group of disorders that affect correct functioning of the immune system. IEI include Tregopathies caused by genetic mutations affecting Treg development or function. In addition, Treg dysfunction is also observed in other IEIs, whose underlying mechanisms are largely unknown, thus requiring further research. This review provides a comprehensive overview and discussion of Treg in IEI focused on: A) advances and controversies in the evaluation of Treg extended subphenotypes and function; B) current knowledge and gaps in Treg disturbances in Tregopathies and other IEI including Treg subpopulation changes, genotype-phenotype correlation, Treg changes with disease activity, and available therapies, and C) the potential of Treg cell-based therapies for IEI with immune dysregulation. The aim is to improve both the diagnostic and the therapeutic approaches to IEI when there is involvement of Treg. We performed a non-systematic targeted literature review with a knowledgeable selection of current, high-quality original and review articles on Treg and IEI available since 2003 (with 58% of the articles within the last 6 years) in the PubMed database.

Clinical Manufacturing of Regulatory T Cell Products For Adoptive Cell Therapy and Strategies to Improve Therapeutic Efficacy

Based on successes in preclinical animal transplant models, adoptive cell therapy (ACT) with regulatory T cells (Tregs) is a promising modality to induce allograft tolerance or reduce the use of immunosuppressive drugs to prevent rejection. Extensive work has been done in optimizing the best approach to manufacture Treg cell products for testing in transplant recipients. Collectively, clinical evaluations have demonstrated that large numbers of Tregs can be expanded ex vivo and infused safely. However, these trials have failed to induce robust drug-free tolerance and/or significantly reduce the level of immunosuppression needed to prevent solid organ transplant (SOTx) rejection. Improving Treg therapy effectiveness may require increasing Treg persistence or orchestrating Treg migration to secondary lymphatic tissues or places of inflammation. In this review, we describe current clinical Treg manufacturing methods used for clinical trials. We also highlight current strategies being implemented to improve delivered Treg ACT persistence and migration in preclinical studies.

Promises and Pitfalls of Next-Generation Treg Adoptive Immunotherapy

Regulatory T cells (Tregs) are fundamental to maintaining immune homeostasis by inhibiting immune responses to self-antigens and preventing the excessive activation of the immune system. Their functions extend beyond immune surveillance and subpopulations of tissue-resident Treg cells can also facilitate tissue repair and homeostasis. The unique ability to regulate aberrant immune responses has generated the concept of harnessing Tregs as a new cellular immunotherapy approach for reshaping undesired immune reactions in autoimmune diseases and allo-responses in transplantation to ultimately re-establish tolerance. However, a number of issues limit the broad clinical applicability of Treg adoptive immunotherapy, including the lack of antigen specificity, heterogeneity within the Treg population, poor persistence, functional Treg impairment in disease states, and in vivo plasticity that results in the loss of suppressive function. Although the early-phase clinical trials of Treg cell therapy have shown the feasibility and tolerability of the approach in several conditions, its efficacy has remained questionable. Leveraging the smart tools and platforms that have been successfully developed for primary T cell engineering in cancer, the field has now shifted towards "next-generation" adoptive Treg immunotherapy, where genetically modified Treg products with improved characteristics are being generated, as regards antigen specificity, function, persistence, and immunogenicity. Here, we review the state of the art on Treg adoptive immunotherapy and progress beyond it, while critically evaluating the hurdles and opportunities towards the materialization of Tregs as a living drug therapy for various inflammation states and the broad clinical translation of Treg therapeutics.

First-in-human therapy with Treg produced from thymic tissue (thyTreg) in a heart transplant infant

Due to their suppressive capacity, regulatory T cells (Tregs) have attracted growing interest as an adoptive cellular therapy for the prevention of allograft rejection, but limited Treg recovery and lower quality of adult-derived Tregs could represent an obstacle to success. To address this challenge, we developed a new approach that provides large quantities of Tregs with high purity and excellent features, sourced from thymic tissue routinely removed during pediatric cardiac surgeries (thyTregs). We report on a 2-year follow-up of the first patient treated worldwide with thyTregs, included in a phase I/II clinical trial evaluating the administration of autologous thyTreg in infants undergoing heart transplantation. In addition to observing no adverse effects that could be attributed to thyTreg administration, we report that the Treg frequency in the periphery was preserved during the 2-year follow-up period. These initial results are consistent with the trial objective, which is to confirm safety of the autologous thyTreg administration and its capacity to restore the Treg pool.

Early Stage Professionals Committee Proceedings from the International Society for Cell & Gene Therapy 2022 Annual Meeting

In this Committee Proceedings, representatives from the Early Stage Professional (ESP) committee highlight the innovative discoveries and key take-aways from oral presentations at the 2022 International Society for Cell and Gene Therapy (ISCT) Annual Meeting that cover the following subject categories: Immunotherapy, Exosomes and Extracellular Vesicles, HSC/Progenitor Cells and Engineering, Mesenchymal Stromal Cells, and ISCT Late-Breaking Abstracts.

Opportunities for Treg cell therapy for the treatment of human disease

Regulatory T (Treg) cells are essential for maintaining peripheral tolerance, preventing autoimmunity, and limiting chronic inflammatory diseases. This small CD4+ T cell population can develop in the thymus and in the peripheral tissues of the immune system through the expression of an epigenetically stabilized transcription factor, FOXP3. Treg cells mediate their tolerogenic effects using multiple modes of action, including the production of inhibitory cytokines, cytokine starvation of T effector (e.g., IL-2), Teff suppression by metabolic disruption, and modulation of antigen-presenting cell maturation or function. These activities together result in the broad control of various immune cell subsets, leading to the suppression of cell activation/expansion and effector functions. Moreover, these cells can facilitate tissue repair to complement their suppressive effects. In recent years, there has been an effort to harness Treg cells as a new therapeutic approach to treat autoimmune and other immunological diseases and, importantly, to re-establish tolerance. Recent synthetic biological advances have enabled the cells to be genetically engineered to achieve tolerance and antigen-specific immune suppression by increasing their specific activity, stability, and efficacy. These cells are now being tested in clinical trials. In this review, we highlight both the advances and the challenges in this arena, focusing on the efforts to develop this new pillar of medicine to treat and cure a variety of diseases.

Manufacturing next-generation regulatory T-cell therapies

Regulatory T-cell (Treg) therapy has shown promise in treating autoimmune diseases, transplant rejection, or graft-versus-host disease in early clinical trials. These trials have demonstrated that cell therapy using polyclonal Tregs is feasible and safe, however, the field has been limited by the lack of polyclonal cell specificity and consequent large cell numbers required, and the difficulty in generating autologous products for some patients. Thus, the field is moving toward 'next generation' Treg cell therapies that include genetic modification strategies to engineer specificity and/or modify function, as well as methods to generate Tregs in vitro. In this review, we describe how genetic modification of Tregs using viral transduction or gene editing may be incorporated into Treg manufacturing protocols. We also describe how Tregs may be generated via FOXP3 gene editing or overexpression, or by differentiation from pluripotent stem cells. The application of these various types of engineered Tregs is discussed.