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Introduction: Point-of-care (POC) manufacturing of chimeric antigen receptor (CAR) modified T cell has expanded rapidly over the last decade. In addition to the use of CD19 CAR T cells for hematological diseases, there is a growing interest in targeting a variety of tumor-associated epitopes. Methods: Here, we report the manufacturing and characterization of autologous anti-CD20 CAR T cells from melanoma patients within phase I clinical trial (NCT03893019). Using a second-generation lentiviral vector for the production of the CD20 CAR T cells on the CliniMACS Prodigy®. Results: We demonstrated consistency in cell composition and functionality of the products manufactured at two different production sites. The T cell purity was >98.5%, a CD4/CD8 ratio between 2.5 and 5.5 and transduction rate between 34% and 61% on day 12 (harvest). Median expansion rate was 53-fold (range, 42-65-fold) with 1.7-3.8×109 CAR T cells at harvest, a sufficient number for the planned dose escalation steps (1×105/kg, 1×106/kg, 1×107/kg BW). Complementary research of some of the products pointed out that the CAR+ cells expressed mainly central memory T-cell phenotype. All tested CAR T cell products were capable to translate into T cell activation upon engagement of CAR target cells, indicated by the increase in pro-inflammatory cytokine release and by the increase in CAR T cell amplification. Notably, there were some interindividual, cell-intrinsic differences at the level of cytokine release and amplification. CAR-mediated T cell activation depended on the level of CAR cognate antigen. Discussion: In conclusion, the CliniMACS Prodigy® platform is well suited for decentralized POC manufacturing of anti-CD20 CAR T cells and may be likewise applicable for the rapid and automated manufacturing of CAR T cells directed against other targets. [ABSTRACT FROM AUTHOR]

BACKGROUND. Adoptive transfer of EBV-specific T cells can restore specific immunity in immunocompromised patients with EBV-associated complications. METHODS. We provide results of a personalized T cell manufacturing program evaluating donor, patient, T cell product, and outcome data. Patient-tailored clinical-grade EBV-specific cytotoxic T lymphocyte (EBV-CTL) products from stem cell donors (SCDs), related third-party donors (TPDs), or unrelated TPDs from the allogeneic T cell donor registry (alloCELL) at Hannover Medical School were manufactured by immunomagnetic selection using a CliniMACS Plus or Prodigy device and the EBV PepTivators EBNA-1 and Select. Consecutive manufacturing processes were evaluated, and patient outcome and side effects were retrieved by retrospective chart analysis. RESULTS. Forty clinical-grade EBV-CTL products from SCDs, related TPDs, or unrelated TPDs were generated for 37 patients with refractory EBV infections or EBV-associated malignancies with and without a history of transplantation, within 5 days (median) after donor identification. Thirty-four patients received 1-14 EBV-CTL products (fresh and cryopreserved). EBV-CTL transfer led to a complete response in 20 of 29 patients who were evaluated for clinical response. No infusion-related toxicity was reported. EBV-specific T cells in patients' blood were detectable in 16 of 18 monitored patients (89%) after transfer, and their presence correlated with clinical response. CONCLUSION. Personalized clinical-grade manufacture of EBV-CTL products via immunomagnetic selection from SCDs, related TPDs, or unrelated TPDs in a timely manner is feasible. Overall, EBV-CTLs were clinically effective and well tolerated. Our data suggest EBV-CTL transfer as a promising therapeutic approach for immunocompromised patients with refractory EBV-associated diseases beyond HSCT, as well as patients with preexisting organ dysfunction. TRIAL REGISTRATION. Not applicable. FUNDING. This study was funded in part by the German Research Foundation (DFG, 158989968/SFB 900), the Deutsche Kinderkrebsstiftung (DKS 2013.09), Wilhelm-Sander-Stiftung (reference 2015.097.1), Ellen-Schmidt-Program of Hannover Medical School, and German Federal Ministry of Education and Research (reference 01E00802)., Introduction Morbidity and mortality in patients with hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT) are frequently caused by graft rejection or graft-versus-host disease (GvHD) and increased by [...]

Chimeric antigen receptor (CAR)-engineered T cells can be highly effective in the treatment of hematological malignancies, but mostly fail in the treatment of solid tumors. Thus, approaches using 4th advanced CAR T cells secreting immunomodulatory cytokines upon CAR signaling, known as TRUCKs (" T cells redirected for universal cytokine-mediated killing "), are currently under investigation. Based on our previous development and validation of automated and closed processing for GMP-compliant manufacturing of CAR T cells, we here present the proof of feasibility for translation of this method to TRUCKs. We generated IL-18-secreting TRUCKs targeting the tumor antigen GD2 using the CliniMACS Prodigy® system using a recently described "all-in-one" lentiviral vector combining constitutive anti-GD2 CAR expression and inducible IL-18. Starting with 0.84 x 108 and 0.91 x 108 T cells after enrichment of CD4+ and CD8+ we reached 68.3-fold and 71.4-fold T cell expansion rates, respectively, in two independent runs. Transduction efficiencies of 77.7% and 55.1% was obtained, and yields of 4.5 x 109 and 3.6 x 109 engineered T cells from the two donors, respectively, within 12 days. Preclinical characterization demonstrated antigen-specific GD2-CAR mediated activation after co-cultivation with GD2-expressing target cells. The functional capacities of the clinical-scale manufactured TRUCKs were similar to TRUCKs generated in laboratory-scale and were not impeded by cryopreservation. IL-18 TRUCKs were activated in an antigen-specific manner by co-cultivation with GD2-expressing target cells indicated by an increased expression of activation markers (e.g. CD25, CD69) on both CD4+ and CD8+ T cells and an enhanced release of pro-inflammatory cytokines and cytolytic mediators (e.g. IL-2, granzyme B, IFN-γ, perforin, TNF-α). Manufactured TRUCKs showed a specific cytotoxicity towards GD2-expressing target cells indicated by lactate dehydrogenase (LDH) release, a decrease of target cell numbers, microscopic detection of cytotoxic clusters and detachment of target cells in real-time impedance measurements (xCELLigence). Following antigen-specific CAR activation of TRUCKs, CAR-triggered release IL-18 was induced, and the cytokine was biologically active, as demonstrated in migration assays revealing specific attraction of monocytes and NK cells by supernatants of TRUCKs co-cultured with GD2-expressing target cells. In conclusion, GMP-compliant manufacturing of TRUCKs is feasible and delivers high quality T cell products. [ABSTRACT FROM AUTHOR]

Several single-nucleotide polymorphisms (SNPs) have been associated with papillary and follicular thyroid cancer (PTC and FTC, respectively) risk, but few have replicated. After analyzing 17 525 tag SNPs in 1129 candidate genes, we found associations with PTC risk in SERPINA5, FTO, HEMGN (near FOXE1) and other genes. Here, we report results from a replication effort in a large independent PTC/FTC case-control study conducted in Germany. We evaluated the best tagging SNPs from our previous PTC study and additionally included SNPs in or near FOXE1 and NKX2-1 genes, known susceptibility loci for thyroid cancer. We genotyped 422 PTC and 130 FTC cases and 752 controls recruited from three German clinical centers. We used polytomous logistic regression to simultaneously estimate PTC and FTC associations for 79 SNPs based on log-additive models. We assessed effect modification by body mass index (BMI), gender and age for all SNPs, and selected SNP by SNP interactions. We confirmed associations with PTC and SNPs in FOXE1/HEMGN, SERPINA5 (rs2069974), FTO (rs8047395), EVPL (rs2071194), TICAM1 (rs8120) and SCARB1 (rs11057820) genes. We found associations with SNPs in FOXE1, SERPINA5, FTO, TICAM1 and HSPA6 and FTC. We found two significant interactions between FTO (rs8047395) and BMI (P = 0.0321) and between TICAM1 (rs8120) and FOXE1 (rs10984377) (P = 0.0006). Besides the known associations with FOXE1 SNPs, we confirmed additional PTC SNP associations reported previously. We also found several new associations with FTC risk and noteworthy interactions. We conclude that multiple variants and host factors might interact in complex ways to increase risk of PTC and FTC. [ABSTRACT FROM AUTHOR]

Background The adoptive transfer of allogeneic antiviral T lymphocytes derived from seropositive donors can safely and effectively reduce or prevent the clinical manifestation of viral infections or reactivations in immunocompromised recipients after hematopoietic stem cell (HSCT) or solid organ transplantation (SOT). Allogeneic third party T-cell donors offer an alternative option for patients receiving an allogeneic cord blood transplant or a transplant from a virusseronegative donor and since donor blood is generally not available for solid organ recipients. Therefore we established a registry of potential third-party T-cell donors (allogeneic cell registry, alloCELL) providing detailed data on the assessment of a specific individual memory T-cell repertoire in response to antigens of cytomegalovirus (CMV), Epstein-Barr virus (EBV), adenovirus (ADV), and human herpesvirus (HHV) 6. Methods To obtain a manufacturing license according to the German Medicinal Products Act, the enrichment of clinical-grade CMV-specific T cells from three healthy CMV-seropositive donors was performed aseptically under GMP conditions using the CliniMACS cytokine capture system (CCS) after restimulation with an overlapping peptide pool of the immunodominant CMVpp65 antigen. Potential T-cell donors were selected from alloCELL and defined as eligible for clinical-grade antiviral T-cell generation if the peripheral fraction of IFN-γ+ T cells exceeded 0.03% of CD3+ lymphocytes as determined by IFN-γ cytokine secretion assay. Results Starting with low concentration of IFN-γ+ T cells (0.07-1.11%) we achieved 81.2%, 19.2%, and 63.1% IFN-γ+CD3+ T cells (1.42×106, 0.05×106, and 1.15×106) after enrichment. Using the CMVpp65 peptide pool for restimulation resulted in the activation of more CMV-specific CD8+ than CD4+ memory T cells, both of which were effectively enriched to a total of 81.0% CD8+IFN-γ+ and 38.4% CD4+IFN-γ+ T cells. In addition to T cells and NKT cells, all preparations contained acceptably low percentages of contaminating B cells, granulocytes, monocytes, and NK cells. The enriched T-cell products were stable over 72 h with respect to viability and ratio of T lymphocytes. Conclusions The generation of antiviral CD4+ and CD8+ T cells by CliniMACS CCS can be extended to a broad spectrum of common pathogen-derived peptide pools in single or multiple applications to facilitate and enhance the efficacy of adoptive T-cell immunotherapy. [ABSTRACT FROM AUTHOR]

Granulocyte colony-stimulating factor (G-CSF) is a major regulator of granulopoiesis on engagement with the G-CSF receptor (G-CSFR). The truncated, alternatively spliced, class IV G-CSFR (G-CSFRIV) has been associated with defective differentiation and relapse risk in pediatric acute myeloid leukemia (AML) patients. However, the detailed biological properties of G-CSFRIV in human CD34+ hematopoietic stem and progenitor cells (HSPCs) and the potential leukemogenic mechanism of this receptor remain poorly understood. In the present study, we observed that G-CSFRIV-overexpressing (G-CSFRIV+) HSPCs demonstrated an enhanced proliferative and survival capacity on G-CSF stimulation. Cell cycle analyses showed a higher frequency of G-CSFRIV+ cells in the S and G2/M phase. Also, apoptosis rates were significantly lower in G-CSFRIV+ HSPCs. These findings were shown to be associated with a sustained Stat5 activation and elevated miR-155 expression. In addition, G-CSF showed tofurther induce G-CSFRIV and miR-155 expression of peripheral blood mononuclear cells isolated from AML patients. A Stat5 pharmacological inhibitor or ribonucleic acid (RNA) interference-mediated silencing of the expression of miR-155 abrogated the aberrant proliferative capacity of the G-CSFRIV+ HSPCs. Hence, the dysregulation of Stat5/miR-155 pathway in the G-CSFRIV+ HSPCs supports their leukemogenic potential. Specific miRNA silencing or the inhibition of Stat5-associated pathways might contribute to preventing the risk of leukemogenesis in G-CSFRIV+ HSPCs. This study may promote the development of a personalized effective antileukemia therapy, in particular for the patients exhibiting higher expression levels of G-CSFRIV, and further highlights the necessity of prescreening the patients for G-CSFR isoforms expression patterns before G-CSF administration. [ABSTRACT FROM AUTHOR]

Integrins are a large family of heterodimeric proteins that are involved in cell adhesion, migration, and proliferation. Integrin diversity and function is regulated by alternative splicing. Membrane-bound and truncated β3-integrins were shown to be key players in cancer metastasis. However, the immunomodulatory functions of the soluble (s) β3-integrin have not been investigated yet. In this study, we described a novel form of sβ3-integrin in acute myeloid leukaemia (AML) patients. Furthermore, we assessed the role of the sβ3-integrin in the modulation of natural killer (NK)-cell activity. Levels of sβ3-integrin were analysed in plasma samples of 23 AML patients and 26 healthy donors by ELISA. The capacity of sβ3-integrin to regulate NK cell activity was investigated using proliferation, cytokine secretion, and cytotoxicity assays. Circulating sβ3-integrin was detected in the plasma of 8 AML patients. NK cells showed significantly higher proliferation rates after stimulation with sβ3-integrin and IL-2, IL-15 (73%). Significant increases in the NK cells’ secreted levels of TNF-α, IFN-γ were measured in presence of sβ3-integrin. In addition, sβ3-integrin caused the upregulation of Granzyme B transcripts levels as well as FasL expression levels in NK cells. Most importantly, significantly higher K562 or AML blast target cell lysis rates were observed when NK cells were exposed to sβ3-integrin. This study reports the identification of a novel sβ3-integrin in AML patients and provides novel insights into its role in the immunomodulation of NK cell activity. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptor (CAR)-engineered T cells can be highly effective in the treatment of hematological malignancies, but mostly fail in the treatment of solid tumors. Thus, approaches using 4 th advanced CAR T cells secreting immunomodulatory cytokines upon CAR signaling, known as TRUCKs (" T cells redirected for universal cytokine-mediated killing "), are currently under investigation. Based on our previous development and validation of automated and closed processing for GMP-compliant manufacturing of CAR T cells, we here present the proof of feasibility for translation of this method to TRUCKs. We generated IL-18-secreting TRUCKs targeting the tumor antigen GD 2 using the CliniMACS Prodigy ® system using a recently described "all-in-one" lentiviral vector combining constitutive anti-GD 2 CAR expression and inducible IL-18. Starting with 0.84 x 10 8 and 0.91 x 10 8 T cells after enrichment of CD4 + and CD8 + we reached 68.3-fold and 71.4-fold T cell expansion rates, respectively, in two independent runs. Transduction efficiencies of 77.7% and 55.1% was obtained, and yields of 4.5 x 10 9 and 3.6 x 10 9 engineered T cells from the two donors, respectively, within 12 days. Preclinical characterization demonstrated antigen-specific GD 2 -CAR mediated activation after co-cultivation with GD 2 -expressing target cells. The functional capacities of the clinical-scale manufactured TRUCKs were similar to TRUCKs generated in laboratory-scale and were not impeded by cryopreservation. IL-18 TRUCKs were activated in an antigen-specific manner by co-cultivation with GD 2 -expressing target cells indicated by an increased expression of activation markers (e.g. CD25, CD69) on both CD4 + and CD8 + T cells and an enhanced release of pro-inflammatory cytokines and cytolytic mediators (e.g. IL-2, granzyme B, IFN-γ, perforin, TNF-α). Manufactured TRUCKs showed a specific cytotoxicity towards GD 2 -expressing target cells indicated by lactate dehydrogenase (LDH) release, a decrease of target cell numbers, microscopic detection of cytotoxic clusters and detachment of target cells in real-time impedance measurements (xCELLigence). Following antigen-specific CAR activation of TRUCKs, CAR-triggered release IL-18 was induced, and the cytokine was biologically active, as demonstrated in migration assays revealing specific attraction of monocytes and NK cells by supernatants of TRUCKs co-cultured with GD 2 -expressing target cells. In conclusion, GMP-compliant manufacturing of TRUCKs is feasible and delivers high quality T cell products., Competing Interests: HA, ASc, and KZ have submitted a patent application describing the “all-in-one” TRUCK vector technology. The University Medicine of Greifswald licensed Ganglidiomab to AnYxis Immuno-oncology for commercialization. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Glienke, Dragon, Zimmermann, Martyniszyn-Eiben, Mertens, Abken, Rossig, Altvater, Aleksandrova, Arseniev, Kloth, Stamopoulou, Moritz, Lode, Siebert, Blasczyk, Goudeva, Schambach, Köhl, Eiz-Vesper and Esser.)

Multiple clinical studies have demonstrated that adaptive immunotherapy using redirected T cells against advanced cancer has led to promising results with improved patient survival. The continuously increasing interest in those advanced gene therapy medicinal products (GTMPs) leads to a manufacturing challenge regarding automation, process robustness, and cell storage. Therefore, this study addresses the proof of principle in clinical-scale selection, stimulation, transduction, and expansion of T cells using the automated closed CliniMACS ® Prodigy system. Naïve and central memory T cells from apheresis products were first immunomagnetically enriched using anti-CD62L magnetic beads and further processed freshly (n = 3) or split for cryopreservation and processed after thawing (n = 1). Starting with 0.5 × 10 8 purified CD3 + T cells, three mock runs and one run including transduction with green fluorescent protein (GFP)-containing vector resulted in a median final cell product of 16 × 10 8 T cells (32-fold expansion) up to harvesting after 2 weeks. Expression of CD62L was downregulated on T cells after thawing, which led to the decision to purify CD62L + CD3 + T cells freshly with cryopreservation thereafter. Most important in the split product, a very similar expansion curve was reached comparing the overall freshly CD62L selected cells with those after thawing, which could be demonstrated in the T cell subpopulations as well by showing a nearly identical conversion of the CD4/CD8 ratio. In the GFP run, the transduction efficacy was 83%. In-process control also demonstrated sufficient glucose levels during automated feeding and medium removal. The robustness of the process and the constant quality of the final product in a closed and automated system give rise to improve harmonized manufacturing protocols for engineered T cells in future gene therapy studies.

Granulocyte colony-stimulating factor (G-CSF) is a major regulator of granulopoiesis on engagement with the G-CSF receptor (G-CSFR). The truncated, alternatively spliced, class IV G-CSFR (G-CSFRIV) has been associated with defective differentiation and relapse risk in pediatric acute myeloid leukemia (AML) patients. However, the detailed biological properties of G-CSFRIV in human CD34(+) hematopoietic stem and progenitor cells (HSPCs) and the potential leukemogenic mechanism of this receptor remain poorly understood. In the present study, we observed that G-CSFRIV-overexpressing (G-CSFRIV(+)) HSPCs demonstrated an enhanced proliferative and survival capacity on G-CSF stimulation. Cell cycle analyses showed a higher frequency of G-CSFRIV(+) cells in the S and G2/M phase. Also, apoptosis rates were significantly lower in G-CSFRIV(+) HSPCs. These findings were shown to be associated with a sustained Stat5 activation and elevated miR-155 expression. In addition, G-CSF showed to further induce G-CSFRIV and miR-155 expression of peripheral blood mononuclear cells isolated from AML patients. A Stat5 pharmacological inhibitor or ribonucleic acid (RNA) interference-mediated silencing of the expression of miR-155 abrogated the aberrant proliferative capacity of the G-CSFRIV(+) HSPCs. Hence, the dysregulation of Stat5/miR-155 pathway in the G-CSFRIV(+) HSPCs supports their leukemogenic potential. Specific miRNA silencing or the inhibition of Stat5-associated pathways might contribute to preventing the risk of leukemogenesis in G-CSFRIV(+) HSPCs. This study may promote the development of a personalized effective antileukemia therapy, in particular for the patients exhibiting higher expression levels of G-CSFRIV, and further highlights the necessity of pre-screening the patients for G-CSFR isoforms expression patterns before G-CSF administration.

Background: Numerous reports have been published on the association between kinetics of leukemic cells during early treatment of childhood acute lymphoblastic leukemia and therapeutic outcome. In contrast, little is known about the prognostic relevance of normal blood counts in this setting., Design and Methods: Normal hematopoiesis during and after induction treatment (days 8, 15 and 33) was correlated with therapeutic outcome in a cohort of 256 children with acute lymphoblastic leukemia treated in one of three consecutive ALL-BFM trials at a single institute. Replication analysis of positive findings was performed in an independent cohort of 475 patients from the ALL-BFM 2000 multicenter trial., Results: A platelet count in the first quartile on treatment day 33 and a neutrophil count above the median on day 8 were significantly associated with treatment outcome, conferring multivariate risk ratios for an event of 3.27 (95% confidence interval 1.60-6.69) and 2.26 (95% confidence interval 1.23-4.29), respectively. Replication analysis confirmed the prognostic effect of platelet count on treatment day 33 and demonstrated a strong association with minimal residual disease-based risk group distribution (P<0.00001)., Conclusions: Platelet counts after induction treatment may improve treatment stratification for patients with childhood acute lymphoblastic leukemia and be of particular interest in non-minimal residual disease-based trials. (ALL-BFM 2000 is registered at: ClinicalTrials.gov: NCT00430118. National Cancer Institute: Protocol ID 68529).

Epidemiological studies have indicated that obesity is associated with a higher risk for certain cancers caused by elevated levels of adipocyte-derived hormones. Leptin, one such hormone produced by adipocytes, is a major regulator of metabolism and has also been shown to modulate immunity. However, its role in regulating human natural killer (NK) cell functions is largely unknown. Here, we show that the leptin receptor (Ob-R) is expressed on 5% of NK cells isolated from blood donors, as measured with flow cytometry, and expression of the signal-transducing long form of the leptin receptor Ob-Rb was confirmed with quantitative PCR. The Ob-R+ subpopulation displayed a lower expression of CD16, a cell surface receptor mediating antibody-dependent activation. Short-term stimulation with leptin increased IFNγ secretion, CD69 activation marker expression, and cytotoxic lysis of tumor cells; this was mediated by an improved conjugate forming between NK cells and tumor cells as well as higher expression of tumor necrosis factor-related apoptosis-inducing ligand. On the contrary, long-term incubation with leptin significantly impaired these NK cell immune functions and decreased cell proliferation. In addition, phosphorylation of Jak-2 after leptin stimulation was reduced in peripheral mononuclear blood cells from obese humans compared with normal-weight controls. NK cells represent an immune cell population that is crucial for an effective antitumor response. Here, we show that long-term exposure to leptin, similarly to the situation in obese individuals with elevated serum leptin levels, significantly impairs integral parts of NK cell immune functions, possibly linking leptin to increased cancer susceptibility in obesity.