Improving TCR Gene Therapy for Treatment of Haematological Malignancies

Adoptive immunotherapy using TCR gene modified T cells may allow separation of beneficial Graft versus tumour responses from harmful GvHD. Improvements to this include methods to generate high avidity or high affinity TCR, improvements in vector design and reduction in mispairing. Following adoptive transfer, TCR transduced T cells must be able to survive and persist in vivo to give most effective antitumour responses. Central memory or naive T cells have both been shown to be more effective than effector cells at expanding and persisting in vivo. Lymphodepletion may enhance persistence of transferred T cell populations. TCR gene transfer can be used to redirect CD4 helper T cells, and these could be used in combination with CD8+ tumour specific T cells to provide help for the antitumour response. Antigen specific T regulatory T cells can also be generated by TCR gene transfer and could be used to suppress unwanted alloresponses

Synthetic Cell-Based Immunotherapies for Neurologic Diseases

The therapeutic success and widespread approval of genetically engineered T cells for a variety of hematologic malignancies spurred the development of synthetic cell-based immunotherapies for CNS lymphoma, primary brain tumors, and a growing spectrum of nononcologic disease conditions of the nervous system. Chimeric antigen receptor effector T cells bear the potential to deplete target cells with higher efficacy, better tissue penetration, and greater depth than antibody-based cell depletion therapies. In multiple sclerosis and other autoimmune disorders, engineered T-cell therapies are being designed and currently tested in clinical trials for their safety and efficacy to eliminate pathogenic B-lineage cells. Chimeric autoantibody receptor T cells expressing a disease-relevant autoantigen as cell surface domains are designed to selectively deplete autoreactive B cells. Alternative to cell depletion, synthetic antigen-specific regulatory T cells can be engineered to locally restrain inflammation, support immune tolerance, or efficiently deliver neuroprotective factors in brain diseases in which current therapeutic options are very limited. In this article, we illustrate prospects and bottlenecks for the clinical development and implementation of engineered cellular immunotherapies in neurologic diseases

Modifications outside CDR1, 2 and 3 of the TCR variable β domain increase TCR expression and antigen-specific function

T cell receptor (TCR) gene modified T cells are a promising form of adoptive cellular therapy against human malignancies and viral infections. Since the first human clinical trial was carried out in 2006, several strategies have been developed to improve the efficacy and safety of TCR engineered T cells by enhancing the surface expression of the introduced therapeutic TCRs whilst reducing the mis-pairing with endogenous TCR chains. In this study, we explored how modifications of framework residues in the TCR variable domains affect TCR expression and function. We used bioinformatic and protein structural analyses to identify candidate amino acid residues in the framework of the variable β domain predicted to drive high TCR surface expression. Changes of these residues in poorly expressed TCRs resulted in improved surface expression and boosted target cell specific killing by engineered T cells expressing the modified TCRs. Overall, these results indicate that small changes in the framework of the TCR variable domains can result in improved expression and functionality, while at the same time reducing the risk of toxicity associated with TCR mis-pairing

Machbarkeitsstudie: Entwicklung und Etablierung eines Netzwerkes von Pilotbetrieben des Ökologischen Landbaus

Die Kritik an der bisherigen Forschungspraxis war Ausgangspunkt für die Suche nach neuen Lösungsansätzen, die die Grundsätze und Praxis des ökologischen Landbaus wieder stärker in den Fordergrund rücken sollen. Die Grundidee besteht darin, die Betriebe als Ganzes in den Mittelpunkt zu stellen und sie als Systeme zu untersuchen. Der Untersuchungszeitraum muss ausreichend lang sein, damit sich Systemveränderungen in entsprechenden Beobachtungsparametern abbilden. In dieser Machbarkeitsstudie wurde untersucht, wie sich ein solcher Forschungsansatz in Zielsetzung und Organisation umsetzen lässt. Die Diskussion mit potenziellen Kooperationspartnern in vier Regional-Workshops in Deutschland und einem Abschlusstreffen führte zu dem Konzept, ein Netzwerk von Pilotbetrieben aufzubauen, in dem Forscher, Berater und Praktiker gleichberechtigt mit den Zielsetzungen zusammenarbeiten: a) das System des ökologischen Landbaus in der Ausprägung unterschiedlicher Betriebe umfassend zu verstehen und weiter zu entwickeln; b) die Produktionsverfahren aus einem besseren Systemverständnis heraus zu optimieren und c) eine Praxis-Forschungs-Plattform als Organisationsstruktur zu etablieren. Um die Systeme zu verstehen, sollen kontinuierlich Betriebsdaten erhoben, gezielte Bestandesbeobachtungen durchgeführt und Messparameter erhoben werden, um diese Betriebssysteme dann als Modell abbilden zu können. Dadurch wird es möglich Entwicklungen und Zusammenhänge in den Betrieben zu erkennen aber auch zu bewerten. Die geplante Praxis-Forschungs-Plattform bildet sowohl die Struktur innerhalb des geplanten Netzwerkes als auch die Möglichkeit, zusätzliche Projekte anzugliedern

Engineering Specificity and Function of Therapeutic Regulatory T Cells

Adoptive therapy with polyclonal regulatory T cells (Tregs) has shown efficacy in suppressing detrimental immune responses in experimental models of autoimmunity and transplantation. The lack of specificity is a potential limitation of Treg therapy, as studies in mice have demonstrated that specificity can enhance the therapeutic potency of Treg. We will discuss that vectors encoding T cell receptors or chimeric antigen receptors provide an efficient gene-transfer platform to reliably produce Tregs of defined antigen specificity, thus overcoming the considerable difficulties of isolating low-frequency, antigen-specific cells that may be present in the natural Treg repertoire. The recent observations that Tregs can polarize into distinct lineages similar to the Th1, Th2, and Th17 subsets described for conventional T helper cells raise the possibility that Th1-, Th2-, and Th17-driven pathology may require matching Treg subsets for optimal therapeutic efficacy. In the future, genetic engineering may serve not only to enforce FoxP3 expression and a stable Treg phenotype but it may also enable the expression of particular transcription factors that drive differentiation into defined Treg subsets. Together, established and recently developed gene transfer and editing tools provide exciting opportunities to produce tailor-made antigen-specific Treg products with defined functional activities

Modifications outside CDR1, 2 and 3 of the TCR variable β domain increase TCR expression and antigen-specific function

T cell receptor (TCR) gene modified T cells are a promising form of adoptive cellular therapy against human malignancies and viral infections. Since the first human clinical trial was carried out in 2006, several strategies have been developed to improve the efficacy and safety of TCR engineered T cells by enhancing the surface expression of the introduced therapeutic TCRs whilst reducing the mis-pairing with endogenous TCR chains. In this study, we explored how modifications of framework residues in the TCR variable domains affect TCR expression and function. We used bioinformatic and protein structural analyses to identify candidate amino acid residues in the framework of the variable β domain predicted to drive high TCR surface expression. Changes of these residues in poorly expressed TCRs resulted in improved surface expression and boosted target cell specific killing by engineered T cells expressing the modified TCRs. Overall, these results indicate that small changes in the framework of the TCR variable domains can result in improved expression and functionality, while at the same time reducing the risk of toxicity associated with TCR mis-pairing

Framework engineering to produce dominant T cell receptors with enhanced antigen-specific function

Immunobiology of allogeneic stem cell transplantation and immunotherapy of hematological disease

Efficacy of a Tyrothricin-Containing Wound Gel in an Abrasive Wound Model for Superficial Wounds

Background: Topical preparations are a common treatment for superficialacute wounds, which at the least do not interfere with healing andideally result in enhanced wound healing irrespective of microbialcolonization. Objective: To examine the effects of a topicalantimicrobial gel and its vehicle on the wound healing of standardized,superficial abrasions. Methods: Thirty-three healthy volunteers wereenrolled in a double-blinded, randomized, intraindividual comparisonstudy. Three standardized, superficial abrasions were induced on theirforearms. A tyrothricin 0.1% gel (Tyrosur (R) gel; EngelhardArzneimittel GmbH & Co. KG, Niederdorfelden, Germany) and its vehiclewere randomly applied to two of the test areas, and one lesion remaineduntreated. Results: A significant improvement of wound healing was seenwith both tyrothricin 0.1% gel and its corresponding vehicle in theclinical assessment. The mean area under the curve (AUC) of woundhealing scores was the same for both preparations and the meanreepithelization scores were comparable at all test points over theentire 12 days. A lower mean AUC representing less reepithelization wasfound for the untreated test fields. Conclusion: The use of tyrothricin0.1% gel and its corresponding vehicle resulted in statisticallysignificant improved wound healing with an earlier onset of healing inparticular. Based on these results obtained using an abrasive woundmodel, it can be concluded that the addition of tyrothricin 0.1% to thegel vehicle did not interfere with the improved wound healing seen withthe vehicle alone

Reconstitution of a functional human thymus by postnatal stromal progenitor cells and natural whole-organ scaffolds.

The thymus is a primary lymphoid organ, essential for T cell maturation and selection. There has been long-standing interest in processes underpinning thymus generation and the potential to manipulate it clinically, because alterations of thymus development or function can result in severe immunodeficiency and autoimmunity. Here, we identify epithelial-mesenchymal hybrid cells, capable of long-term expansion in vitro, and able to reconstitute an anatomic phenocopy of the native thymus, when combined with thymic interstitial cells and a natural decellularised extracellular matrix (ECM) obtained by whole thymus perfusion. This anatomical human thymus reconstruction is functional, as judged by its capacity to support mature T cell development in vivo after transplantation into humanised immunodeficient mice. These findings establish a basis for dissecting the cellular and molecular crosstalk between stroma, ECM and thymocytes, and offer practical prospects for treating congenital and acquired immunological diseases