Adoptive T-cell Immunotherapy Research Articles

Adoptive T-cell Immunotherapy: Perfecting Self-Defenses.

As an important part of the immune system, T lymphocytes exhibit undoubtedly an important role in targeting and eradicating cancer. However, despite these characteristics, their natural antitumor response may be insufficient. Numerous clinical trials in terminally ill cancer patients testing the design of novel and efficient immunotherapeutic approaches based on the adoptive transfer of autologous tumor-specific T lymphocytes have shown encouraging results. Moreover, this also led to the approval of engineered T-cell therapies in patients. Herein, we will expand on the development and the use of such strategies using tumor-infiltrating lymphocytes or genetically engineered T-cells. We will also comment on the requirements and potential hurdles encountered when elaborating and implementing such treatments as well as the exciting prospects for this kind of emerging personalized medicine therapy.

HBV-HCC treatment with mRNA electroporated HBV-TCR T cells.

Hepatocellular carcinoma is a significant global health challenge with steadily increasing incidence in the East Asia region. While both Hepatitis C and B virus infections account for the majority of HCC cases, the advent of potent antivirals against HCV infection has biased the aetiology towards chronic HBV infection that at the moment remains without an effective cure. For this reason, HBV-HCC remains a persistent global problem. Treatment options for intermediate to advanced stages of HBV-HCC remain limited, hence novel therapeutic strategies are required to fulfil this medical need. Following the considerable success of adoptive T-cell immunotherapy against B-cell malignancies, it is conceivable to envision whether the same could be achieved against HBV-HCC. In this review, we describe the development of T-cell therapy strategies for HBV-HCC and discuss the safety and the efficacy of the strategies in terms of the direct killing of tumour cells and the other alterations possibly induced by the action of the T cells.

Cancer-cell stiffening via cholesterol depletion enhances adoptive T-cell immunotherapy.

Malignancy and tumour progression are associated with cancer-cell softening. Yet how the biomechanics of cancer cells affects T-cell mediated cytotoxicity and thus the outcomes of adoptive T-cell immunotherapies is unknown. Here, we show that T-cell-mediated cancer-cell killing is hampered for cortically soft cancer cells, whose plasma membrane is enriched with cholesterol, and that cancer-cell stiffening via cholesterol depletion augments T-cell cytotoxicity and enhances the efficacy of adoptive T-cell therapy against solid tumours in mice. We also show that the enhanced cytotoxicity against stiffened cancer cells is mediated by augmented T-cell forces arising from an increased accumulation of filamentous actin at the immunological synapse, and that cancer-cell stiffening has a negligible influence on T-cell-receptor signalling, on the production of cytolytic proteins such as granzyme B, on the secretion of interferon gamma and tumour necrosis factor alpha, and on Fas-receptor–Fas-ligand interactions. Our findings reveal a mechanical immune checkpoint that could be targeted therapeutically to improve the effectiveness of cancer immunotherapies.Cancer cells enriched with cholesterol in their plasma membrane impair T-cell mediated cytotoxicity, which can be augmented by stiffening the cancer cells via cholesterol depletion, as shown in mouse models of adoptive T-cell therapy.

Augmenting Adoptive T-cell Immunotherapy by Targeting the PD-1/PD-L1 Axis.

Cancer immunotherapy utilizing checkpoint blockade antibodies or adoptive cellular therapy (ACT) with tumor-specific T cells has led to unprecedented clinical responses in patients with cancer and has been considered one of the most significant breakthroughs in cancer treatment in the past decade. Nevertheless, many cancers remain refractory to these therapies due to the presence of an immunosuppressive tumor microenvironment. This has led to the innovative idea of combining ACT with checkpoint inhibition. A landmark 2004 study by Blank and colleagues published in Cancer Research was one of the original demonstrations that adoptive transfer of T cells lacking the negative T-cell regulator, PD-1, was able to restore functional T-cell antitumor activity, resulting in rapid regression of established tumors in a preclinical model. This work was instrumental in not only driving clinical studies utilizing checkpoint inhibition but also a new wave of recent trials involving checkpoint blockade in the setting of ACT.See related article by Blank and colleagues, Cancer Res 2004;64:1140-5.

Immunotherapy for Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is characterized by extensive tumor heterogeneity at both the pathologic and molecular levels, particularly accelerated aggressiveness, and terrible metastasis. It is responsible for the increased mortality of breast cancer patients. Due to the negative expression of estrogen receptors, progesterone receptors, and human epidermal growth factor receptor 2, the progress of targeted therapy has been hindered. Higher immune response in TNBCs than for other breast cancer types makes immunotherapy suitable for TNBC therapy. At present, promising treatments in immunotherapy of TNBC include immune checkpoints (ICs) blockade therapy, adoptive T-cell immunotherapy, and tumor vaccine immunotherapy. In addition, nanomedicines exhibit great potential in cancer therapy through the enhanced permeability and retention (EPR) effect. Immunotherapy-involved combination therapy may exert synergistic effects by combining with other treatments, such as traditional chemotherapy and new treatments, including photodynamic therapy (PTT), photodynamic therapy (PDT), and sonodynamic therapy (SDT). This review focuses on introducing the principles and latest development as well as progress in using nanocarriers as drug-delivery systems for the immunotherapy of TNBC.

Trial Watch: Adoptive TCR-Engineered T-Cell Immunotherapy for Acute Myeloid Leukemia.

Simple SummaryAcute myeloid leukemia (AML) is a type of blood cancer with an extremely grim prognosis. This is due to the fact that the majority of patients will relapse after frontline treatment. Overall survival of relapsed AML is very low, and treatment options are few. T lymphocytes harnessed with antitumor T-cell receptors (TCRs) can produce objective clinical responses in certain cancers, such as melanoma, but have not entered the main road for AML. In this review, we describe the current status of the field of TCR-T-cell therapies for AML.Despite the advent of novel therapies, acute myeloid leukemia (AML) remains associated with a grim prognosis. This is exemplified by 5-year overall survival rates not exceeding 30%. Even with frontline high-intensity chemotherapy regimens and allogeneic hematopoietic stem cell transplantation, the majority of patients with AML will relapse. For these patients, treatment options are few, and novel therapies are urgently needed. Adoptive T-cell therapies represent an attractive therapeutic avenue due to the intrinsic ability of T lymphocytes to recognize tumor cells with high specificity and efficiency. In particular, T-cell therapies focused on introducing T-cell receptors (TCRs) against tumor antigens have achieved objective clinical responses in solid tumors such as synovial sarcoma and melanoma. However, contrary to chimeric antigen receptor (CAR)-T cells with groundbreaking results in B-cell malignancies, the use of TCR-T cells for hematological malignancies is still in its infancy. In this review, we provide an overview of the status and clinical advances in adoptive TCR-T-cell therapy for the treatment of AML.

Updates on the diagnosis, current and future therapeutic options in Merkel-cell carcinoma.

Merkel-cell carcinoma (MCC) is a rare and extremely aggressive nonmelanocytic cutaneous neuroendocrine carcinoma. Historically, it has been associated with limited therapy options and poor prognosis. While its incidence has been rising over the last two decades, recent discoveries and a better understanding of its pathogenesis, viral association and immunologic features have allowed for the emergence of new therapies. Surgical excision with or without radiotherapy remains the first-line therapy for primary lesions without evidence of metastatic disease. The majority of MCC cases are regrettably diagnosed at advanced stages and oftentimes require systemic therapy. There have been several significant advances in the treatment of MCC in the last decade. Among these have been the development of immune checkpoint inhibitors targeting the programmed death protein-1 (PD-1)/programmed death ligand-1 (PDL-1). Despite recent success of immunotherapy, nearly 50% of patients diagnosed with MCC still succumb to the disease. Fortunately, there has been a number of new targeted therapies that hold great promise. Among them are phosphatidylinositide-3kinase (Pl3K) inhibitors, adoptive T-cell immunotherapy, activated NK-92 cells infusions and therapeutic vaccines. Additional emerging therapeutic targets include cellular ubiquitin-specific processing protease 7 (Usp7) that restricts viral replication and IFN genes (STING), activation of which promotes an antitumor inflammatory response.

Haploidentical age-adapted myeloablative transplant and regulatory and effector T cells for acute myeloid leukemia

Allogeneic hematopoietic stem cell transplantation (HSCT) is the most effective treatment in eradicating high-risk acute myeloid leukemia (AML). Here, we present data from a novel HLA-haploidentical HSCT protocol that addressed the 2 remaining major unmet medical needs: leukemia relapse and chronic graft-versus-host disease (cGVHD). Fifty AML patients were enrolled in the study. The conditioning regimen included total body irradiation for patients up to age 50 years and total marrow/lymphoid irradiation for patients age 51 to 65 years. Irradiation was followed by thiotepa, fludarabine, and cyclophosphamide. Patients received an infusion of 2 × 106/kg donor regulatory T cells on day −4 followed by 1 × 106/kg donor conventional T cells on day −1 and a mean of 10.7 × 106 ± 3.4 × 106/kgpurified CD34+ hematopoietic progenitor cells on day 0. No pharmacological GVHD prophylaxis was administered posttransplantation. Patients achieved full donor–type engraftment. Fifteen patients developed grade ≥2 acute GVHD (aGVHD). Twelve of the 15 patients with aGVHD were alive and no longer receiving immunosuppressive therapy. Moderate/severe cGVHD occurred in only 1 patient. Nonrelapse mortality occurred in 10 patients. Only 2 patients relapsed. Consequently, at a median follow-up of 29 months, the probability of moderate/severe cGVHD/relapse-free survival was 75% (95% confidence interval, 71%-78%). A novel HLA-haploidentical HSCT strategy that combines an age-adapted myeloablative conditioning regimen with regulatory and conventional T-cell adoptive immunotherapy resulted in an unprecedented cGVHD/relapse-free survival rate in 50 AML patients with a median age of 53 years. This trial was registered with the Umbria Region Institutional Review Board Public Registry as identification code 02/14 and public registry #2384/14 and at www.clinicaltrials.gov as #NCT03977103.

CAR Tcells as drugs for novel therapies (advanced therapy medicinal products)

Two commercial chimeric antigen receptor (CAR) T cell products, axicabtagene-ciloleucel (Yescarta®) and tisagenlecleucel (Kymriah®), are registered for the treatment of B cell neoplasia, for which an increased supply of CAR T cell products is required. The production of patient-specific CAR T cells as advanced therapy medicinal products (ATMPs) poses considerable challenges with respect to logistics, regulation, and manufacturing. Review of the CAR Tcell manufacturing process and the regulatory network, the current challenges, and future development capabilities of CAR Tcells for adoptive immunotherapy. CAR Tcells are manufactured under individualized, laborious, good manufacturing practice-conforming processes in decentralized or in specialized centers. Starting from the patient's leukapheresis product, Tcells are genetically engineered ex vivo with aCAR, amplified, and after extensive quality control re-applied to the patient. Most CAR Tcell products are manufactured in amanual or semi-automated process; fully automated, supervised, and closed systems are increasingly applied to meet the need for agrowing number of CAR Tcell products. In this setting, research aims at providing allogeneic CAR Tcell products or non-Tcells such as natural killer cells for broad applications. The significance of CAR Tcells in adoptive immunotherapy is continuously growing. As individualized cell products, manufacturing requires highly efficient processes under the control of harmonized protocols and regulations so as to ensure the quality of the ATMP in view of increasing demand and to develop new fields in therapy.

The combination therapy with EpCAM/CD3 BsAb and MUC-1/CD3 BsAb elicited antitumor immunity by T-cell adoptive immunotherapy in lung cancer.

Lung cancer remains a global challenge due to high morbidity and mortality rates and poor response to treatment, and there are still no effective strategies to solve it. The bispecific antibody (BsAb) is a novel antibody, which can target two different antigens and mediate specific killing effects by selectively redirecting effector cells to the target cells. In this study, we combined two BsAbs to achieve a dual-target therapy strategy of EpCAM+ and MUC-1+ with high affinity and specificity. The results showed that the combination of two BsAbs against EpCAM and MUC-1 could inhibit the growth of lung cancer more effectively in cell lines and primary tumors. The superior antitumor effect of two BsAbs could be attributable to enhanced CTL and increased production of type I IFNs. At the same time, the combination of EpCAM/CD3 BsAb and MUC-1/CD3 BsAb significantly regulated T population in the TDLNs. Therefore, we have found a potential immunotherapeutic strategy, which was the combination therapy with EpCAM/CD3 BsAb and MUC-1/CD3 BsAb for the treatment of non-small cell lung cancer.

Engineering advanced dynamic biomaterials to optimize adoptive T-cell immunotherapy

Adoptive T-cell therapy (ACT) is a promising therapeutic approach based on the concept of potent T-cell mediated immunity against the tumor. The outcome of antigen-specific T-cells responses relies on the interaction between T-cells and antigen-presenting cells, which provides signals for generating different T-cell phenotypes with different roles in tumor removal. However, such interaction is often not optimal in vivo and results in low therapeutic efficacy. To reach the full potential of the T-cell response, current research put effort into developing dynamic biomaterials as artificial antigen-presenting cells to study and regulate the T-cell activity for controlling T-cell fate. In this perspective, we provide (1) an overview of ACT and general T-cells behaviors, (2) explore the insight on how biomaterials can be used for studying and regulating T-cell behaviors, (3) and discuss conceptual gaps in knowledge for biomaterials-based immunotherapy.

Adoptive transfer of neoantigen-specific T-cell therapy is feasible in older patients with higher-risk myelodysplastic syndrome

BackgroundMyelodysplastic syndromes (MDS) represent the most common type of acquired bone marrow failure in adults and is characterized by ineffective maturation of myeloid precursor cells and peripheral cytopenias associated with higher rates of infection, bleeding and transfusion dependence. In higher-risk patients with MDS who relapse or do not respond after standard hypomethylating agent (HMA) therapy, the 2-year survival rate is 15%. MethodsHere the authors report the feasibility and safety of a novel experimental T-cell therapy called personalized adoptive cell therapy, which selects, immunizes and expands T cells against MDS-specific mutations and is targeted to patient-specific tumor cell neoantigens. Somatic mutations serve as the pathogenic drivers of cancer, including MDS, as these transformative genetic mutations may generate novel immunogenic proteins (i.e., neopeptides and possible neoantigens) that may be targeted therapeutically. ResultsThe authors demonstrate that the adaptive immune system can be trained ex vivo to recognize neopeptides as neoantigens and that the infusion of culture-expanded, neoantigen-immunized autologous T cells has been feasible and safe in the three patients treated to date. DiscussionThe authors report on early results from their first-in-human phase 1 clinical trial that aims to assess the safety and tolerability of this novel form of adoptive T-cell immunotherapy for HMA-refractory patients with higher-risk MDS.

The CAR T-Cell Mechanoimmunology at a Glance.

Chimeric antigen receptor (CAR) T‐cell transfer is a novel paradigm of adoptive T‐cell immunotherapy. When coming into contact with a target cancer cell, CAR T‐cell forms a nonclassical immunological synapse with the cancer cell and dynamically orchestrates multiple critical forces to commit cytotoxic immune function. Such an immunologic process involves a force transmission in the CAR and a spatiotemporal remodeling of cell cytoskeleton to facilitate CAR activation and CAR T‐cell cytotoxic function. Yet, the detailed understanding of such mechanotransduction at the interface between the CAR T‐cell and the target cell, as well as its molecular structure and signaling, remains less defined and is just beginning to emerge. This article summarizes the basic mechanisms and principles of CAR T‐cell mechanoimmunology, and various lessons that can be comparatively learned from interrogation of mechanotransduction at the immunological synapse in normal cytotoxic T‐cell. The recent development and future application of novel bioengineering tools for studying CAR T‐cell mechanoimmunology is also discussed. It is believed that this progress report will shed light on the CAR T‐cell mechanoimmunology and encourage future researches in revealing the less explored yet important mechanosensing and mechanotransductive mechanisms involved in CAR T‐cell immuno‐oncology.

Cellular Uptake of siRNA-Loaded Nanocarriers to Knockdown PD-L1: Strategies to Improve T-cell Functions.

T-cells are a type of lymphocyte (a subtype of white blood cells) that play a central role in cell-mediated immunity. Currently, adoptive T-cell immunotherapy is being developed to destroy cancer cells. In this therapy, T-cells are harvested from a patient’s blood. After several weeks of growth in culture, tumor-specific T-cells can be reinfused into the same cancer patient. This technique has proved highly efficient in cancer treatment. However, there are several biological processes that can suppress the anti-cancer responses of T-cells, leading to a loss of their functionality and a reduction of their viability. Therefore, strategies are needed to improve T-cell survival and their functions. Here, a small interfering RNA (siRNA)-loaded nanocarrier was used to knockdown PD-L1, one of the most important proteins causing a loss in the functionality of T-cells. The biocompatibility and the cellular uptake of siRNA-loaded silica nanocapsules (SiNCs) were investigated in CD8+ T-cells. Then, the PD-L1 expression at protein and at mRNA levels of the treated cells were evaluated. Furthermore, the effect of the PD-L1 knockdown was observed in terms of cell proliferation and the expression of specific biomarkers CD25, CD69 and CD71, which are indicators of T-cell functions. The results suggest that this siRNA-loaded nanocarrier showed a significant potential in the delivery of siRNA into T-cells. This in turn resulted in enhanced T-cell survival by decreasing the expression of the inhibitory protein PD-L1. Such nanocarriers could, therefore, be applied in adoptive T-cell immunotherapy for the treatment of cancer.

Effect of adoptive T-cell immunotherapy on immunological parameters and prognosis in patients with advanced pancreatic cancer

Background aimsImmunotherapy is effective for many types of cancer, but its benefits in advanced pancreatic cancer, which has a poor prognosis, are not well established. In this study, the authors examined the effects of adoptive T-cell immunotherapy (ATI) on immune cell profiles and prognosis in patients with unresectable advanced pancreatic cancer. MethodsSeventy-seven patients with unresectable advanced pancreatic cancer were treated with six cycles of αβ T cells alone or in combination with chemotherapy or chemoradiation. Immune cell profiles in peripheral blood samples obtained before and after treatment were comprehensively evaluated by flow cytometry. Furthermore, associations between changes in immune cell frequencies and prognosis were determined. ResultsATI prolonged survival to 18.7 months compared with previous estimates of 6.2–11.1 months for patients treated with chemotherapy alone. ATI decreased CD3+CD4+CD8− T cell frequency in peripheral blood and increased CD3+CD4−CD8+ T cell frequency. An increase in CD3+ T cells and CD3+TCRγδ− T cells in peripheral blood after treatment was associated with a good prognosis. ConclusionsATI altered the immune profile in peripheral blood, including CD3+CD4−CD8+ T cells, and improved prognosis in pancreatic cancer.

Silica Nanocapsules with Different Sizes and Physicochemical Properties as Suitable Nanocarriers for Uptake in T-Cells.

IntroductionAdoptive T-cell immunotherapy emerged as a powerful and promising cancer therapy, as the problem regarding the immuno-reaction between different donors and recipients can be avoided. However, this approach is challenging. After long cultivation and expansion under laboratory media conditions, T-cells are losing their viability and function due to immune checkpoint proteins, leading to decreased efficiency in killing cancer cells. Therefore, a new strategy to improve T-cell survival and function is needed. With the advantages of nanotechnology and the biocompatibility of silica-based material, silica nanocapsules (SiNCs) provide an ideal delivery system to transport therapeutic biomolecules to T-cells. Up to now, there is a lack of cellular uptake studies of nanocarriers towards T-cells.MethodsWe systematically studied the influence of various physicochemical properties such as sizes, core hydrophobicities, surface charges, and surface functionalities of SiNC for their impact on cellular uptake and toxicity in CD8+ T-cells by flow cytometry and confocal laser scanning microscopy. Cytokine secretion assay was performed using the enzyme-linked immunosorbent assay. To identify suitable uptake conditions for SiNCs into CD8+ T-cells, the impact of human serum in cell culture medium was also investigated.ResultsThe major impact on cellular uptake and toxicity was found to be size- and dose-dependent. Smaller sizes of SiNCs than 100 nm caused significant toxicity to the cells. It was found that the formed protein corona reduced the toxicity of the SiNCs. However, it also inhibited their uptake.ConclusionOverall, we present a set of different criteria for a suitable design of nanocarriers and cell culture conditions, which need to be carefully considered for T-cell immunotherapy in vitro to facilitate uptake while avoiding toxicity.

Axicabtagene Ciloleucel: Clinical Data for the Use of CAR T-cell Therapy in Relapsed and Refractory Large B-cell Lymphoma.

To evaluate the literature for axicabtagene ciloleucel (axi-cel), a first-in-class chimeric antigen receptor (CAR) T-cell therapy, in the treatment of relapsed/refractory (r/r) large B-cell lymphoma (LBCL). We conducted a PubMed (inception to June 22, 2020) and ClinicalTrials.gov search using the following terms: CD19, chimeric antigen receptor, and lymphoma. All retrospective and prospective studies evaluating the use of axi-cel in LBCL were reviewed. In the pivotal ZUMA-1 trial, axi-cel exhibited unprecedented overall and complete response rates of 83% and 58%, respectively. With a median follow-up of 27.1 months, 39% of patients had ongoing responses. Furthermore, postmarketing retrospective analyses found similar response rates in a more clinically diverse LBCL patient population. Novel CAR T-cell therapy elicits unique and potentially life-threatening toxicities that include cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Studies reported grade ≥3 CRS in 7% to 14% of patients and grade ≥3 ICANS in 31% to 55% of patients. Axi-cel was the first US Food and Drug Administration-approved genetically engineered autologous CAR T-cell agent in r/r LBCL, representing an important milestone and paradigm shift in cancer treatment. Adoptive T-cell immunotherapy is a breakthrough treatment modality requiring careful patient selection, multidisciplinary collaboration, comprehensive patient counseling, and expert training to ensure optimal treatment. The initial and ongoing results with axi-cel are encouraging, but long-term safety and efficacy data are lacking. Additional studies are required to identify axi-cel's ideal place in LBCL therapy.

The CD4+ T Cell Response to Human Cytomegalovirus in Healthy and Immunocompromised People.

While CD8+ T cells specific for human cytomegalovirus (HCMV) have been extensively studied in both healthy HCMV seropositive carriers and patients undergoing immunosuppression, studies on the CD4+ T cell response to HCMV had lagged behind. However, over the last few years there has been a significant advance in our understanding of the importance and contribution that CMV-specific CD4+ T cells make, not only to anti-viral immunity but also in the potential maintenance of latently infected cells. During primary infection with HCMV in adults, CD4+ T cells are important for the resolution of symptomatic disease, while persistent shedding of HCMV into urine and saliva is associated with a lack of HCMV specific CD4+ T cell response in young children. In immunosuppressed solid organ transplant recipients, a delayed appearance of HCMV-specific CD4+ T cells is associated with prolonged viremia and more severe clinical disease, while in haematopoietic stem cell transplant recipients, it has been suggested that HCMV-specific CD4+ T cells are required for HCMV-specific CD8+ T cells to exert their anti-viral effects. In addition, adoptive T-cell immunotherapy in transplant patients has shown that the presence of HCMV-specific CD4+ T cells is required for the maintenance of HCMV-specific CD8+ T cells. HCMV is a paradigm for immune evasion. The presence of viral genes that down-regulate MHC class II molecules and the expression of viral IL-10 both limit antigen presentation to CD4+ T cells, underlining the important role that this T cell subset has in antiviral immunity. This review will discuss the antigen specificity, effector function, phenotype and direct anti-viral properties of HCMV specific CD4+ T cells, as well as reviewing our understanding of the importance of this T cell subset in primary infection and long-term carriage in healthy individuals. In addition, their role and importance in congenital HCMV infection and during immunosuppression in both solid organ and haemopoietic stem cell transplantation is considered.

Raman spectroscopy for adaptive process control of adoptive T-cell immunotherapy manufacture

Background & Aim The majority of adoptive T-cell immunotherapies currently in clinical trials are autologous in nature. Their manufacture is constrained by fixed processes that typically allow for little, if any, adaptive control. Manufacturing platforms also have few real-time sensing technologies (biomass, glucose, pH and DO) and provide read-outs which are weak surrogate predictors of culture behaviour and quality. In this study we demonstrate the potential of Raman spectroscopy as a Process Analytical Technology (PAT). Methods, Results & Conclusion Method: A total of 6 healthy donor leukapheresis samples were processed to isolate T-cells. These were then activated and expanded in a stirred tank bioreactor over a period of 10 days. Raman spectroscopy was performed in situ in real-time, every hour and was supplemented with off-line characterisation of cell counts, viability, immunophenotying, and metabolomics. For 2 donors, full transcriptomics analysis, mass cytometry and mitochondrial potential were also performed. Results Unlike the outputs of current inline sensors, the multidimensional nature of Raman spectra allowed the development of chemometric models for cell concentration, cell viability, and a range of metabolites which correlated to cell quality. These models could be applied hourly to get a real-time snapshot of the culture status, thus providing the ability to make rapid process decisions. Together with the multivariate characterisation of the cells and medium, this approach provided a comprehensive description of the system's behaviour, paving the way for the design of informed specifications and tolerances which could be used as part of an adaptive control strategy. Conclusion The use of Raman spectroscopy for adaptive control could compensate for inherent patient-to-patient variability, providing a robust manufacturing process that can consistently meet release acceptance criteria. It could also help reduce product cycle times through optimal bioprocessing and have significant impact on the overall cost of autologous T-cell manufacturing.

High-intensity interval training in allogeneic adoptive T-cell immunotherapy \u2013 a big HIT?

BackgroundAdoptive transfer of virus-specific T cells (VSTs) represents a prophylactic and curative approach for opportunistic viral infections and reactivations after transplantation. However, inadequate frequencies of circulating memory VSTs in the T-cell donor’s peripheral blood often result in insufficient enrichment efficiency and purity of the final T-cell product, limiting the effectiveness of this approach.MethodsThis pilot study was designed as a cross-over trial and compared the effect of a single bout (30 min) of high-intensity interval training (HIT) with that of 30 min of continuous exercise (CONT) on the frequency and function of circulating donor VSTs. To this end, we used established immunoassays to examine the donors’ cellular immune status, in particular, with respect to the frequency and specific characteristics of VSTs restricted against Cytomegalovirus (CMV)-, Epstein–Barr-Virus (EBV)- and Adenovirus (AdV)-derived antigens. T-cell function, phenotype, activation and proliferation were examined at different time points before and after exercise to identify the most suitable time for T-cell donation. The clinical applicability was determined by small-scale T-cell enrichment using interferon- (IFN-) γ cytokine secretion assay and virus-derived overlapping peptide pools.ResultsHIT proved to be the most effective exercise program with up to fivefold higher VST response. In general, donors with a moderate fitness level had higher starting and post-exercise frequencies of VSTs than highly fit donors, who showed significantly lower post-exercise increases in VST frequencies. Both exercise programs boosted the number of VSTs against less immunodominant antigens, specifically CMV (IE-1), EBV (EBNA-1) and AdV (Hexon, Penton), compared to VSTs against immunodominant antigens with higher memory T-cell frequencies.ConclusionThis study demonstrates that exercise before T-cell donation has a beneficial effect on the donor’s cellular immunity with respect to the proportion of circulating functionally active VSTs. We conclude that a single bout of HIT exercise 24 h before T-cell donation can significantly improve manufacturing of clinically applicable VSTs. This simple and economical adjuvant treatment proved to be especially efficient in enhancing virus-specific memory T cells with low precursor frequencies.