Phospholipase D Mediates Glutamine-Induced mTORC1 Activation to Promote Porcine Intestinal Epithelial Cell Proliferation.

BACKGROUND: The intestinal epithelium is one of the fastest self-renewal tissues in the body, and glutamine plays a crucial role in providing carbon and nitrogen for biosynthesis. In intestinal homeostasis, phosphorylation-mediated signaling networks that cause altered cell proliferation, differentiation, and metabolic regulation have been observed. However, our understanding of how glutamine affects protein phosphorylation in the intestinal epithelium is limited, and identifying the essential signaling pathways involved in regulating intestinal epithelial cell growth is particularly challenging. OBJECTIVES: This study aimed to identify the essential proteins and signaling pathways involved in glutamine's promotion of porcine intestinal epithelial cell proliferation. METHODS: Phosphoproteomics was applied to describe the protein phosphorylation landscape under glutamine treatment. Kinase-substrate enrichment analysis was subjected to predict kinase activity and validated by qRT-PCR and Western blotting. Cell Counting Kit-8, glutamine rescue experiment, chloroquine treatment, and 5-fluoro-2-indolyl deschlorohalopemide inhibition assay revealed the possible underlying mechanism of glutamine promoting porcine intestinal epithelial cell proliferation. RESULTS: In this study, glutamine starvation was found to significantly suppress the proliferation of intestinal epithelial cells and change phosphoproteomic profiles with 575 downregulated sites and 321 upregulated sites. Interestingly, phosphorylation of eukaryotic initiation factor 4E-binding protein 1 at position Threonine70 was decreased, which is a crucial downstream of the mechanistic target of rapamycin complex 1 (mTORC1) pathway. Further studies showed that glutamine supplementation rescued cell proliferation and mTORC1 activity, dependent on lysosomal function and phospholipase D activation. CONCLUSION: In conclusion, glutamine activates mTORC1 signaling dependent on phospholipase D and a functional lysosome to promote intestinal epithelial cell proliferation. This discovery provides new insight into regulating the homeostasis of the intestinal epithelium, particularly in pig production.

Two-Stage Machine Learning-Based Approach to Predict Points of Departure for Human Noncancer and Developmental/Reproductive Effects.

Chemical points of departure (PODs) for critical health effects are crucial for evaluating and managing human health risks and impacts from exposure. However, PODs are unavailable for most chemicals in commerce due to a lack of in vivo toxicity data. We therefore developed a two-stage machine learning (ML) framework to predict human-equivalent PODs for oral exposure to organic chemicals based on chemical structure. Utilizing ML-based predictions for structural/physical/chemical/toxicological properties from OPERA 2.9 as features (Stage 1), ML models using random forest regression were trained with human-equivalent PODs derived from in vivo data sets for general noncancer effects (n = 1,791) and reproductive/developmental effects (n = 2,228), with robust cross-validation for feature selection and estimating generalization errors (Stage 2). These two-stage models accurately predicted PODs for both effect categories with cross-validation-based root-mean-squared errors less than an order of magnitude. We then applied one or both models to 34,046 chemicals expected to be in the environment, revealing several thousand chemicals of moderate concern and several hundred chemicals of high concern for health effects at estimated median population exposure levels. Further application can expand by orders of magnitude the coverage of organic chemicals that can be evaluated for their human health risks and impacts.

Evaluating scientific confidence in the concordance of in vitro and in vivo protective points of departure.

To fulfil the promise of reducing reliance on mammalian in vivo laboratory animal studies, new approach methods (NAMs) need to provide a confident basis for regulatory decision-making. However, previous attempts to develop in vitro NAMs-based points of departure (PODs) have yielded mixed results, with PODs from U.S. EPA's ToxCast, for instance, appearing more conservative (protective) but poorly correlated with traditional in vivo studies. Here, we aimed to address this discordance by reducing the heterogeneity of in vivo PODs, accounting for species differences, and enhancing the biological relevance of in vitro PODs. However, we only found improved in vitro-to-in vivo concordance when combining the use of Bayesian model averaging-based benchmark dose modeling for in vivo PODs, allometric scaling for interspecies adjustments, and human-relevant in vitro assays with multiple induced pluripotent stem cell-derived models. Moreover, the available sample size was only 15 chemicals, and the resulting level of concordance was only fair, with correlation coefficients <0.5 and prediction intervals spanning several orders of magnitude. Overall, while this study suggests several ways to enhance concordance and thereby increase scientific confidence in vitro NAMs-based PODs, it also highlights challenges in their predictive accuracy and precision for use in regulatory decision making.

Reducing uncertainty in dose-response assessments by incorporating Bayesian benchmark dose modeling and in vitro data on population variability.

There are two primary sources of uncertainty in the interpretability of toxicity values, like the reference dose (RfD): estimates of the point of departure (POD) and the absence of chemical-specific human variability data. We hypothesize two solutions-employing Bayesian benchmark dose (BBMD) modeling to refine POD determination and combining high-throughput toxicokinetic modeling with population-based toxicodynamic in vitro data to characterize chemical-specific variability. These hypotheses were tested by deriving refined probabilistic estimates for human doses corresponding to a specific effect size (M) in the Ith population percentile (HDM I) across 19 Superfund priority chemicals. HDM I values were further converted to biomonitoring equivalents in blood and urine for benchmarking against human data. Compared to deterministic default-based RfDs, HDM I values were generally more protective, particularly influenced by chemical-specific data on interindividual variability. Incorporating chemical-specific in vitro data improved precision in probabilistic RfDs, with a median 1.4-fold reduction in uncertainty variance. Comparison with US Environmental Protection Agency's Exposure Forecasting exposure predictions and biomonitoring data from the National Health and Nutrition Examination Survey identified chemicals with margins of exposure nearing or below one. Overall, to mitigate uncertainty in regulatory toxicity values and guide chemical risk management, BBMD modeling and chemical-specific population-based human in vitro data are essential.

Design and Implementation of Dongba Character Font Style Transfer Model Based on AFGAN.

Dongba characters are ancient ideographic scripts with abstract expressions that differ greatly from modern Chinese characters; directly applying existing methods cannot achieve the font style transfer of Dongba characters. This paper proposes an Attention-based Font style transfer Generative Adversarial Network (AFGAN) method. Based on the characteristics of Dongba character images, two core modules are set up in the proposed AFGAN, namely void constraint and font stroke constraint. In addition, in order to enhance the feature learning ability of the network and improve the style transfer effect, the Convolutional Block Attention Module (CBAM) mechanism is added in the down-sampling stage to help the network better adapt to input font images with different styles. The quantitative and qualitative analyses of the generated font and the real font were conducted by consulting with professional artists based on the newly built small seal script, slender gold script, and Dongba character dataset, and the styles of the small seal script and slender gold script were transferred to Dongba characters. The results indicate that the proposed AFGAN method has advantages in evaluation indexes and visual quality compared to existing networks. At the same time, this method can effectively learn the style features of small seal script and slender gold script, and transfer them to Dongba characters, indicating the effectiveness of this method.

Design and Experiment of an Unoccupied Control System for a Tracked Grain Vehicle.

In order to enhance crop harvesting efficiency, an automatic-driving tracked grain vehicle system was designed. Based on the harvester chassis, we designed the mechanical structure of a tracked grain vehicle with a loading capacity of 4.5 m3 and a grain unloading hydraulic system. Using the BODAS hydraulic controller, we implemented the design of an electronic control system that combines the manual and automatic operation of the chassis walking mechanism and grain unloading mechanism. We utilized a hybrid A* algorithm to plan the traveling path of the tracked grain vehicle, and the path-tracking controller of the tracked grain vehicle was designed by combining fuzzy control and pure pursuit algorithms. Leveraging binocular vision technology and semantic segmentation technology, we designed an automatic grain unloading control system with functions of grain tank recognition and grain unloading regulation control. Finally, we conducted experiments on automatic grain unloading control and automatic navigation control in the field. The results showed that both the precision of the path-tracking control and the automatic unloading system meet the requirements for practical unoccupied operations of the tracked grain vehicle.

Piceatannol Alleviates Deoxynivalenol-Induced Damage in Intestinal Epithelial Cells via Inhibition of the NF-κB Pathway.

Deoxynivalenol (DON) is a common mycotoxin that is widely found in various foods and feeds, posing a potential threat to human and animal health. This study aimed to investigate the protective effect of the natural polyphenol piceatannol (PIC) against DON-induced damage in porcine intestinal epithelial cells (IPEC-J2 cells) and the underlying mechanism. The results showed that PIC promotes IPEC-J2 cell proliferation in a dose-dependent manner. Moreover, it not only significantly relieved DON-induced decreases in cell viability and proliferation but also reduced intracellular reactive oxygen species (ROS) production. Further studies demonstrated that PIC alleviated DON-induced oxidative stress damage by increasing the protein expression levels of the antioxidant factors NAD(P)H quinone oxidoreductase-1 (NQO1) and glutamate-cysteine ligase modifier subunit (GCLM), and the mRNA expression of catalase (CAT), Superoxide Dismutase 1 (SOD1), peroxiredoxin 3 (PRX3), and glutathione S-transferase alpha 4 (GSTα4). In addition, PIC inhibited the activation of the nuclear factor-B (NF-κB) pathway, downregulated the mRNA expression of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) to attenuate DON-induced inflammatory responses, and further mitigated DON-induced cellular intestinal barrier injury by regulating the protein expression of Occludin. These findings indicated that PIC had a significant protective effect against DON-induced damage. This study provides more understanding to support PIC as a feed additive for pig production.

Immunosuppressive Drug-Resistant Armored T-Cell Receptor T Cells for Immune Therapy of HCC in Liver Transplant Patients.

BACKGROUND AND AIMS: HBV-specific T-cell receptor (HBV-TCR) engineered T cells have the potential for treating HCC relapses after liver transplantation, but their efficacy can be hampered by the concomitant immunosuppressive treatment required to prevent graft rejection. Our aim is to molecularly engineer TCR-T cells that could retain their polyfunctionality in such patients while minimizing the associated risk of organ rejection. APPROACH AND RESULTS: We first analyzed how immunosuppressive drugs can interfere with the in vivo function of TCR-T cells in liver transplanted patients with HBV-HCC recurrence receiving HBV-TCR T cells and in vitro in the presence of clinically relevant concentrations of immunosuppressive tacrolimus (TAC) and mycophenolate mofetil (MMF). Immunosuppressive Drug Resistant Armored TCR-T cells of desired specificity (HBV or Epstein-Barr virus) were then engineered by concomitantly electroporating mRNA encoding specific TCRs and mutated variants of calcineurin B (CnB) and inosine-5'-monophosphate dehydrogenase (IMPDH), and their function was assessed through intracellular cytokine staining and cytotoxicity assays in the presence of TAC and MMF. Liver transplanted HBV-HCC patients receiving different immunosuppressant drugs exhibited varying levels of activated (CD39+ Ki67+ ) peripheral blood mononuclear cells after HBV-TCR T-cell infusions that positively correlate with clinical efficacy. In vitro experiments with TAC and MMF showed a potent inhibition of TCR-T cell polyfunctionality. This inhibition can be effectively negated by the transient overexpression of mutated variants of CnB and IMPDH. Importantly, the resistance only lasted for 3-5 days, after which sensitivity was restored. CONCLUSIONS: We engineered TCR-T cells of desired specificities that transiently escape the immunosuppressive effects of TAC and MMF. This finding has important clinical applications for the treatment of HBV-HCC relapses and other pathologies occurring in organ transplanted patients.

Use of Expression Profiles of HBV-DNA Integrated Into Genomes of Hepatocellular Carcinoma Cells to Select T Cells for Immunotherapy.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is often associated with hepatitis B virus (HBV) infection. Cells of most HBV-related HCCs contain HBV-DNA fragments that do not encode entire HBV antigens. We investigated whether these integrated HBV-DNA fragments encode epitopes that are recognized by T cells and whether their presence in HCCs can be used to select HBV-specific T-cell receptors (TCRs) for immunotherapy. METHODS: HCC cells negative for HBV antigens, based on immunohistochemistry, were analyzed for the presence of HBV messenger RNAs (mRNAs) by real-time polymerase chain reaction, sequencing, and Nanostring approaches. We tested the ability of HBV mRNA-positive HCC cells to generate epitopes that are recognized by T cells using HBV-specific T cells and TCR-like antibodies. We then analyzed HBV gene expression profiles of primary HCCs and metastases from 2 patients with HCC recurrence after liver transplantation. Using the HBV-transcript profiles, we selected, from a library of TCRs previously characterized from patients with self-limited HBV infection, the TCR specific for the HBV epitope encoded by the detected HBV mRNA. Autologous T cells were engineered to express the selected TCRs, through electroporation of mRNA into cells, and these TCR T cells were adoptively transferred to the patients in increasing numbers (1 × 104-10 × 106 TCR+ T cells/kg) weekly for 112 days or 1 year. We monitored patients' liver function, serum levels of cytokines, and standard blood parameters. Antitumor efficacy was assessed based on serum levels of alpha fetoprotein and computed tomography of metastases. RESULTS: HCC cells that did not express whole HBV antigens contained short HBV mRNAs, which encode epitopes that are recognized by and activate HBV-specific T cells. Autologous T cells engineered to express TCRs specific for epitopes expressed from HBV-DNA in patients' metastases were given to 2 patients without notable adverse events. The cells did not affect liver function over a 1-year period. In 1 patient, 5 of 6 pulmonary metastases decreased in volume during the 1-year period of T-cell administration. CONCLUSIONS: HCC cells contain short segments of integrated HBV-DNA that encodes epitopes that are recognized by and activate T cells. HBV transcriptomes of these cells could be used to engineer T cells for personalized immunotherapy. This approach might be used to treat a wider population of patients with HBV-associated HCC.

Intrahepatic CD206+ macrophages contribute to inflammation in advanced viral-related liver disease.

BACKGROUND & AIMS: Liver inflammation is key in the progression of chronic viral hepatitis to cirrhosis and hepatocellular carcinoma. The magnitude of viral replication and the specific anti-viral immune responses should govern the degree of inflammation, but a direct correlation is not consistently found in chronic viral hepatitis patients. We aim to better define the mechanisms that contribute to chronic liver inflammation. METHODS: Intrahepatic CD14+ myeloid cells from healthy donors (n=19) and patients with viral-related liver cirrhosis (HBV, HBV/HDV or HCV; n=15) were subjected to detailed phenotypic, molecular and functional characterisation. RESULTS: Unsupervised analysis of multi-parametric data showed that liver disease was associated with the intrahepatic expansion of activated myeloid cells mainly composed of pro-inflammatory CD14+HLA-DRhiCD206+ cells, which spontaneously produced TNFα and GM-CSF. These cells only showed heightened pro-inflammatory responses to bacterial TLR agonists and were more refractory to endotoxin-induced tolerance. A liver-specific enrichment of CD14+HLA-DRhiCD206+ cells was also detected in a humanised mouse model of liver inflammation. This accumulation was abrogated following oral antibiotic treatment, suggesting a direct involvement of translocated gut-derived microbial products in liver injury. CONCLUSIONS: Viral-related chronic liver inflammation is driven by the interplay between non-endotoxin-tolerant pro-inflammatory CD14+HLA-DRhiCD206+ myeloid cells and translocated bacterial products. Deciphering this mechanism paves the way for the development of therapeutic strategies specifically targeting CD206+ myeloid cells in viral-related liver disease patients. Lay summary: Viral-related chronic liver disease is driven by intrahepatic pro-inflammatory myeloid cells accumulating in a gut-derived bacterial product-dependent manner. Our findings support the use of oral antibiotics to ameliorate liver inflammation in these patients.

Structural evolution and solvation of the OH radical in ionized water radical cations (H2O)n(+), n = 5-8.

Structural evolution of ionized water radical cations (H2O)n(+), n = 5-8, is studied by ab intio methods. A structure searching method based on the previous understanding of the hydrogen bond (H-bond) network in neutral and protonated water clusters is found to be effective, covering a wide range of structural isomers of (H2O)n(+). With these local minima, we can analyze both the size and temperature dependence of the structure of (H2O)n(+) and solvation of the OH radical. Agreement between our calculated IR spectra and experimental data in the free OH stretching region confirms that the OH radical preferred to stay on the terminal site of the H-bond network at n = 5 and n = 6. Furthermore, we found that the OH radical began to form H-bonds with water molecules as a H-bond donor at n = 7 and 8. Vibrational signatures of fully solvated OH were found to be located at 3200-3400 cm(-1) coinciding with the additional peaks found in previous experimental data obtained by Mizuse and Fujii.

Arf1 promotes porcine intestinal epithelial cell proliferation via the mTORC1 signaling pathway.

The promotion of gut health, a pervasive problem in modern animal husbandry, positively affects organismal health, productivity, and economics. Porcine intestinal epithelial cells (IPEC-J2) continuously proliferate to maintain intestinal homeostasis, including barrier, immune, and absorptive functions. Gut homeostasis is fundamental to organismal health. ADP-ribosylation factor 1 (Arf1), a small GTPase, plays a crucial role in coordinating mTORC1 in response to nutrients, especially amino acid availability in the gut. mTORC1 is the central hub of proliferation. Thus, it seems likely that Arf1 promotes IPEC-J2 cell proliferation. However, the exact role of Arf1 in the porcine gut remains unclear. Therefore, we evaluated the functional role and possible mechanisms of Arf1 in the porcine intestine through Arf1 overexpression and knockdown in IPEC-J2 cells. Arf1 overexpression and knockdown significantly enhanced and inhibited, respectively, IPEC-J2 cell viability, and PCNA expression varied with Arf1 expression. Moreover, the proportion of Ki67-positive cells was significantly greater in the Arf1-overexpressing group than in the control group. These results suggest that Arf1 improves IPEC-J2 cell proliferation. The underlying mechanism was explored by Western blotting. Arf1 overexpression and knockdown significantly enhanced and suppressed, respectively, the levels of p-S6K1 and p-RPS6, which are key downstream targets of the mTORC1 signaling pathway. Collectively, our findings reveal the role of the Arf1-mTORC1 axis in IPEC-J2 cell proliferation and its potential function in regulating intestinal homeostasis and health.

Glutamine Promotes Porcine Intestinal Epithelial Cell Proliferation through the Wnt/ß-Catenin Pathway.

Glutamine (Gln) is a critical nutrient required by neonatal mammals for intestinal growth, especially for newborn piglets. However, the mechanisms underlying the role of Gln in porcine intestinal epithelium development are not fully understood. The objective of the current study was to explore the possible signaling pathway involved in the promotion of porcine intestinal epithelial cell (IPEC-J2) proliferation by Gln. The results showed that 1 mM Gln promoted IPEC-J2 cell proliferation, and tandem mass tag proteomics revealed 973 differentially expressed proteins in Gln-treated IPEC-J2 cells, 824 of which were upregulated and 149 of which were downregulated. Moreover, gene set enrichment analysis indicated that the Wnt signaling pathway is activated by Gln treatment. Western blotting analysis further confirmed that Gln activated the Wnt/ß-catenin signaling pathway. In addition, Gln increased not only cytosolic ß-catenin but also nuclear ß-catenin protein expression. LF3 (a ß-catenin/TCF4 interaction inhibitor) assay and ß-catenin knockdown demonstrated that Gln-mediated promotion of Wnt/ß-catenin signaling and cell proliferation were blocked. Furthermore, the inhibition of TCF4 expression suppressed Gln-induced cell proliferation. These findings further confirmed that Wnt/ß-catenin signaling is involved in the promotion of IPEC-J2 cell proliferation by Gln. Collectively, these findings demonstrated that Gln positively regulated IPEC-J2 cell proliferation through the Wnt/ß-catenin pathway. These data greatly enhance the current understanding of the mechanism by which Gln regulates intestinal development.

Distinct roles for the NK cell-activating receptors in mediating interactions with dendritic cells and tumor cells.

NK cells are innate immune cells that are important in tumor immunity, but also have the ability to modulate the adaptive immune system through cytokine production or direct cell-cell interactions. This study investigates the interaction of NK cells with dendritic cells (DCs) and tumor cells, and the role of specific NK cell-activating receptors in this process. Primary rat NK cells and an NK cell line produced IFN-γ when cocultured with either DCs or the rat hepatoma cell line McA-RH7777 (McA). This NK cell activation by DCs and McA required cell-cell contact and was dependent on distinct NK-activating receptors. Silencing NK cell expression of NKp46 and NKp30 significantly diminished DC- and McA-mediated NK cell IFN-γ production, respectively. NK cells killed immature and mature DCs independently of NKp46, NKp30, and NKG2D; however, cytotoxicity against McA cells was dependent on NKp30 and NKG2D. Thus, we have shown in this study that NKp30 plays dual activating roles in NK-McA tumor interactions by mediating cytokine production and cytotoxicity. More importantly, NK cells are activated by both DCs and hepatoma cells to produce IFN-γ, but require distinct NK cell-activating receptors, NKp46 and NKp30, respectively. Our data suggest that therapeutics could be developed specifically to target NK-DC interactions without compromising NK tumor immunity.

Extracellular Glutamine Promotes Intestinal Porcine Epithelial Cell Proliferation via Arf1-mTORC1 Pathway Independently of Rag GTPases.

Glutamine (Gln) is the major energy source of intestinal porcine epithelial cells (IPEC-J2 cells) and plays a critical role in the nutritional physiological function of the intestine. However, the underlying mechanism requires further investigation. Here, the Gln-sensing pathway in IPEC-J2 cells was investigated. The results showed that Gln increased the cell proliferation. Subsequently, an analysis of the phosphorylated proteome revealed that Gln markedly upregulated ribosomal protein S6 (RPS6) phosphorylation at serine 235/236, suggesting that Gln activated the mTORC1 pathway. mTOR inhibition revealed that Gln promotes cell proliferation through the mTORC1 pathway. Similarly, blocking ADP-ribosylation factor 1 (Arf1) activity indicated that Gln-induced mTORC1 activation promoted cell proliferation in an Arf1-dependent manner. Additionally, the RagA/B pathway did not participate in Gln-induced mTORC1 activation. Collectively, these findings suggest that Gln-induced mTORC1 activation promotes IPEC-J2 cell proliferation via Arf1, not Rag GTPases. These results broaden our understanding of functional-cell-sensing amino acids, particularly Gln, that are regulated by mTORC1.

Advancing probabilistic risk assessment by integrating human biomonitoring, new approach methods, and Bayesian modeling: A case study with the mycotoxin deoxynivalenol.

Deoxynivalenol (DON) is a mycotoxin frequently observed in cereals and cereal-based foods, with reported toxicological effects including reduced body weight, immunotoxicity and reproductive defects. The European Food Safety Authority used traditional risk assessment approaches to derive a deterministic Tolerable Daily Intake (TDI) of 1 µg/kg-day, however data from human biomarkers studies indicate widespread and variable exposure worldwide, necessitating more sophisticated and advanced methods to quantify population risk. The World Health Organization/International Programme on Chemical Safety (WHO/IPCS) has previously used DON as a case example in replacing the TDI with a probabilistic toxicity value, using default uncertainty and variability distributions to derive the Human Dose corresponding to an effect size M in the Ith percentile of the population (HDMI) for M = 5 % decrease in body weight and I = 1 %. In this study, we extend this case study by incorporating (1) Bayesian modeling approaches, (2) using both in vivo data and in vitro population new approach methods to replace default distributions for interspecies toxicokinetic (TK) differences and intraspecies TK and toxicodynamic (TD) variability, and (3) integrating biomonitoring data and probabilistic dose-response functions to characterize population risk distributions. We first derive an HDMI of 5.5 [1.4-24] µg/kg-day, also using TK modeling to converted the HDMI to Biomonitoring Equivalents, BEMI for comparison with biomonitoring data, with a blood BEMI of 0.53 [0.17-1.6] µg/L and a urinary excretion BEMI of 3.9 [1.0-16] µg/kg-day. We then illustrate how this integrative approach can advance quantitative risk characterization using two human biomonitoring datasets, estimating both the fraction of population with an effect size M ≥ 5 % as well as the distribution of effect sizes. Overall, we demonstrate that integration of Bayesian modeling, human biomonitoring data, and in vitro population-based TD data within the WHO/IPCS probabilistic framework yields more accurate, precise, and comprehensive risk characterization.

Lytic efficiency of immunosuppressive drug-resistant armoured T cells against circulating HBV-related HCC in whole blood.

Recurrence of hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) after liver transplant (LT) is mediated by circulating tumour cells (CTCs) and exacerbated by the immunosuppressants required to prevent graft rejection. To circumvent the effects of immunosuppressants, we developed immunosuppressive drug-resistant armoured HBV-specific T-cell receptor-redirected T cells (IDRA HBV-TCR). However, their ability to eliminate HBV-HCC circulating in the whole blood has never been tested, and whether their lytic efficacy is compatible with the number of adoptively transferred T cells in vivo has never been measured. Hence, we developed a microscopy-based assay to quantify CTCs in whole blood. The assay was then used to quantify the efficacy of IDRA HBV-TCRs to lyse free-floating HBV-HCC cells in the presence of Tacrolimus and Mycophenolate Mofetil (MMF). We demonstrated that a panel of antibodies (AFP, GPC3, Vimentin, pan-Cytokeratin, and CD45) specific for HCC tumour antigens and immune cells can effectively differentiate HCC-CTCs in whole blood. Through dose-titration experiments, we observed that in the presence of immunosuppressive drugs, a minimum of 20 000 IDRA HBV-TCR T cells/ml of whole blood is necessary to lyse ~63.5% of free-floating HBV-HCC cells within 16 hours. In conclusion, IDRA HBV-TCR T cells can lyse free-floating HBV-HCC cells in whole blood in the presence of Tacrolimus and MMF. The quantity of IDRA-HBV TCR T cells required can be achieved by the adoptive transfer of 5 × 106 IDRA-HBV TCR-T cells/kg, supporting the utilisation of IDRA HBV-TCR T cells to eliminate CTCs as prophylaxis against recurrence after LT.

Messenger RNA electroporated hepatitis B virus (HBV) antigen-specific T cell receptor (TCR) redirected T cell therapy is well-tolerated in patients with recurrent HBV-related hepatocellular carcinoma post-liver transplantation: results from a phase I trial.

BACKGROUND AND AIMS: Liver transplantation (LT) is the primary curative option for cirrhotic patients with early-stage hepatocellular carcinoma (HCC). However, tumor recurrence occurs in 15-20% of cases with unfavorable prognosis. We have developed a library of T cell receptors (TCRs) specific for different hepatitis B virus (HBV) antigens, restricted by different molecules of human leucocyte antigen (HLA)-class I, to redirect T cells against HBV antigens (Banu in Sci Rep 4:4166, 2014). We further demonstrated that these transiently functional T cells specific for HBV obtained through messenger RNA (mRNA) electroporation can eliminate HCC cells expressing HBV antigens in vitro and in vivo (Kah in J Clin Invest 127:3177-3188, 2017). A phase I clinical trial for patients with HCC recurrence post-liver transplant was conducted to assess the safety, tolerability, and anti-tumor efficacy of transiently functional HBV-TCR T cells. Here, we report the clinical findings with regard to the safety and anti-tumor efficacy of mRNA electroporated HBV-specific TCR-T cells. (ClinicalTrials.gov identifier: NCT02719782). PATIENTS AND METHODS: A total of six patients with HBV-positive recurrent HCC post-liver transplant and HLA-matched to TCR targeting hepatitis B surface antigen (HBsAg) or hepatitis B core antigen (HBcAg) (HLA-A*02:01/HBsAg, HLA-A*11:01/HBcAg, HLA-B*58:01/HBsAg or HLA-C*08:01/HBsAg) were enrolled in this study. The primary objective was to assess the safety of short-lived mRNA electroporated HBV-TCR T cells based on the incidence and severity of the adverse event (AE) graded per National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE), Version 4.0. The secondary objective was to determine the effectiveness of HBV-TCR T cells as per RECIST 1.1 criteria. Patients were followed up for survival for 2 years post-end of treatment. RESULTS: The median age of the six patients was 35.5 years (range: 28-47). The median number of HBV-TCR T cell infusions administered was 6.5 (range: 4-12). The treatment-related AE included grade 1 pyrexia. This study reported no cytokine release syndrome nor neurotoxicity. One patient remained alive and five were deceased at the time of the data cutoff (30 April 2020). CONCLUSION: This study has demonstrated that multiple infusions of mRNA electroporated HBV-specific TCR T cells were well-tolerated in patients with HBV-positive recurrent HCC post-liver transplant.

Engineering immunosuppressive drug-resistant armored (IDRA) SARS-CoV-2 T cells for cell therapy.

Solid organ transplant (SOT) recipients receive immunosuppressive drugs (ISDs) and are susceptible to developing severe COVID-19. Here, we analyze the Spike-specific T-cell response after 3 doses of mRNA vaccine in a group of SOT patients (n = 136) treated with different ISDs. We demonstrate that a combination of a calcineurin inhibitor (CNI), mycophenolate mofetil (MMF), and prednisone (Pred) treatment regimen strongly suppressed the mRNA vaccine-induced Spike-specific cellular response. Such defects have clinical consequences because the magnitude of vaccine-induced Spike-specific T cells was directly proportional to the ability of SOT patients to rapidly clear SARS-CoV-2 after breakthrough infection. To then compensate for the T-cell defects induced by immunosuppressive treatment and to develop an alternative therapeutic strategy for SOT patients, we describe production of 6 distinct SARS-CoV-2 epitope-specific ISD-resistant T-cell receptor (TCR)-T cells engineered using the mRNA electroporation method with reactivity minimally affected by mutations occurring in Beta, Delta, Gamma, and Omicron variants. This strategy with transient expression characteristics marks an improvement in the immunotherapeutic field and provides an attractive and novel therapeutic possibility for immunosuppressed COVID-19 patients.

Immunological alterations after immunotherapy with short lived HBV-TCR T cells associates with long-term treatment response in HBV-HCC.

The application of hepatitis B virus (HBV)-T-cell receptor (TCR) T-cell immunotherapy in patients with HBV-related hepatocellular carcinoma (HBV-HCC) has been apathetic, as the expression of HBV antigens by both normal HBV-infected hepatocytes and HCC cells with HBV-DNA integration increases the risk of on-target off-tumor severe liver inflammatory events. To increase the safety of this immunotherapeutic approach, we developed messenger RNA (mRNA) HBV-TCR-redirected T cells that-due to the transient nature of mRNA-are functionally short lived and can be infused in escalating doses. The safety of this approach and its clinical potential against primary HBV-HCC have never been analyzed in human trials; thus, we studied the clinical and immunological parameters of 8 patients with chronic HBV infection and diffuse nonoperable HBV-HCC treated at weekly intervals with escalating doses (1 × 104 , 1 × 105 , 1 × 106 , and 5 × 106 TCR+ T cells/kg body weight) of T cells modified with HBV-TCR encoding mRNA. The treatment was well tolerated with no severe systemic inflammatory events, cytokine storm, or neurotoxicity observed in any of these patients throughout treatment. Instead, we observed a destruction of the tumor lesion or a prolonged stable disease in 3 of 8 patients. Importantly, the patients without clinically relevant reductions of HCC did not display any detectable peripheral blood immunological alterations. In contrast, signs of transient localized liver inflammation, activation of the T-cell compartment, and/or elevations of serum chemokine (C-X-C motif) ligand (CXCL) 9 and CXCL10 levels were detected in patients with long-term clinical benefit. Conclusion: We show that despite the reduced in vivo half-life (3-4 days), adoptive transfer of mRNA HBV-TCR T cells into patients with HBV-HCC show long-term clinical benefit that was associated with transient immunological alterations.