scholarly journals The S enantiomer of 2-hydroxyglutarate increases central memory CD8 populations and improves CAR-T therapy outcome

2020 ◽  
Vol 4 (18) ◽  
pp. 4483-4493
Author(s):  
Iosifina P. Foskolou ◽  
Laura Barbieri ◽  
Aude Vernet ◽  
David Bargiela ◽  
Pedro P. Cunha ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antitumor Activity ◽  
Cd8 T Cells ◽  
Ex Vivo ◽  
Phase 1 ◽  
Therapeutic Success ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T

Abstract Cancer immunotherapy is advancing rapidly and gene-modified T cells expressing chimeric antigen receptors (CARs) show particular promise. A challenge of CAR-T cell therapy is that the ex vivo–generated CAR-T cells become exhausted during expansion in culture, and do not persist when transferred back to patients. It has become clear that naive and memory CD8 T cells perform better than the total CD8 T-cell populations in CAR-T immunotherapy because of better expansion, antitumor activity, and persistence, which are necessary features for therapeutic success and prevention of disease relapse. However, memory CAR-T cells are rarely used in the clinic due to generation challenges. We previously reported that mouse CD8 T cells cultured with the S enantiomer of the immunometabolite 2-hydroxyglutarate (S-2HG) exhibit enhanced antitumor activity. Here, we show that clinical-grade human donor CAR-T cells can be generated from naive precursors after culture with S-2HG. S-2HG–treated CAR-T cells establish long-term memory cells in vivo and show superior antitumor responses when compared with CAR-T cells generated with standard clinical protocols. This study provides the basis for a phase 1 clinical trial evaluating the activity of S-2HG–treated CD19-CAR-T cells in patients with B-cell malignancies.

Ex Vivo AKT Inhibition Promotes the Generation of Potent CD19CAR T Cells for Adoptive Immunotherapy

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3086-3086
Author(s):  
Ryan Urak ◽  
ChingLam Wong ◽  
Wen-Chung Chang ◽  
Elizabeth E. Budde ◽  
Christine Brown ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antitumor Activity ◽  
Ex Vivo ◽  
Akt Inhibitor ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T

Abstract Insufficient persistence and effector function of Chimeric Antigen Receptor (CAR) re-directed T cells in vivo has been a challenge for adoptive T cell therapy. Generation of long-lived potent CAR T cells is an increasing demand in the field. AKT activation triggered by convergent extracellular signals evokes a transcription program that enhances effector functions. However, sustained AKT activation severely impairs T cell memory and protective immunity because AKT drives differentiation of effectors, therefore diminishing T cell potential to survive and differentiate into memory cells. We now investigate whether inhibition of AKT signaling during ex vivo expansion can prevent terminal differentiation of CD19- chimeric antigen receptor (CD19 CAR) engineered T cells and increase the number of memory CD19 CAR T cells, which would enhance the antitumor activity following adoptive therapy. CD8+ T cells from healthy donors were isolated, activated with CD3/CD28 beads, and then transduced with a lentiviral vector encoding a second-generation CD19CAR containing a CD28 co-stimulatory domain and two mutations (L235E; N297Q) within the CH2 region on the IgG4-Fc spacers which enhances potency and persistence by blocking Fc receptor binding. In addition, the lentiviral construct also expresses a truncated human epidermal growth factor receptor (huEGFRt) which allows us to use as a selectable marker and a mechanism to ablate the CAR T cells if necessary. IL-2 (50U/mL) and AKT inhibitor (1uM/mL) were supplemented every other day. Transduced CD19CAR T cells without AKT inhibitor treatment were used as controls. The engineered CD19CAR T cells were expanded in vitro for 21 days before in vitro and in vivo analyses. We found that AKT inhibitor did not compromise the CD19CAR T cell proliferation and survival in vitro. There was a comparable CD19CAR T cell expansion after culturing in the presence or absence AKT inhibitor. Functionally, AKT inhibitor did not dampen the effector function of CD19CAR T cells as indicated by equivalent levels of interferon gamma production and CD107a expression upon CD19 antigen stimulation. Memory-like phenotype such as CD62L and CD28 expression on CAR T cells is associated with better antitumor activity in vivo. We therefore characterized the CD19CAR T cells after ex vivo expansion. We found that 40% of AKT-inhibited CD19CAR T cells expressed CD62L and co-expressed CD28. More importantly, no exhaustion markers such as KRLG and PD-1 were induced on the AKT inhibitor treated cells. In contrast, only 10% of control untreated CD19CAR T cells expressed CD62L and they were CD28 negative, indicating that AKT-inhibited CD19CAR T cells with higher levels of CD62L and CD28 expression may have superior anti-tumor activity following adoptive transfer. To test the potency of the AKT inhibitor treated CAR T cells, 0.5x106 CD19+ acute lymphoid leukemic cells (SupB15) engineered to express firefly luciferase were inoculated intravenously into NOD/Scid IL-2RgammaCnull (NSG) mice. Five days post tumor engraftment, 2x106 CD8+ CD19CAR T cells were intravenously injected into tumor bearing mice. Control mice received either no T cells, non-transduced T cells (Mock), or CD19CAR T cells that were not treated with AKT inhibitor during in vitro expansion. Tumor signals post T cell infusion were monitored by biophotonic imaging. Compared to the untreated CD19CAR T cells, which exhibited lower and transient anti-tumor activity, AKT inhibitor treated CD19CAR T cells completely eradicated the CD19+ tumor in all mice (Figure 1) 21 days post CD19CAR T cell infusion. In conclusion, our results demonstrate that inhibition of AKT signaling during the ex vivo priming and expansion gives rise to a CD19CAR T cell population that possesses superior antitumor activity. These findings suggest that ex vivo therapeutic modulation of AKT might be a strategy to augment antitumor immunity for adoptive CAR T cell therapy, which could easily be transitioned into the clinic with the availability of pharmaceutical grade AKT inhibitor. Disclosures Forman: Amgen: Consultancy; Mustang: Research Funding.

scholarly journals Enhanced CAR-T activity against established tumors by polarizing human T cells to secrete interleukin-9

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Lintao Liu ◽  
Enguang Bi ◽  
Xingzhe Ma ◽  
Wei Xiong ◽  
Jianfei Qian ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antitumor Activity ◽  
Effector Memory ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T ◽  
Ifn Γ

AbstractCAR-T cell therapy is effective for hematologic malignancies. However, considerable numbers of patients relapse after the treatment, partially due to poor expansion and limited persistence of CAR-T cells in vivo. Here, we demonstrate that human CAR-T cells polarized and expanded under a Th9-culture condition (T9 CAR-T) have an enhanced antitumor activity against established tumors. Compared to IL2-polarized (T1) cells, T9 CAR-T cells secrete IL9 but little IFN-γ, express central memory phenotype and lower levels of exhaustion markers, and display robust proliferative capacity. Consequently, T9 CAR-T cells mediate a greater antitumor activity than T1 CAR-T cells against established hematologic and solid tumors in vivo. After transfer, T9 CAR-T cells migrate effectively to tumors, differentiate to IFN-γ and granzyme-B secreting effector memory T cells but remain as long-lived and hyperproliferative T cells. Our findings are important for the improvement of CAR-T cell-based immunotherapy for human cancers.

Presence of Endogenous TCR Antigen in Vivo Attenuates Efficacy of Anti-CD19 Targeted CAR T Cell Therapy

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3721-3721
Author(s):  
Yinmeng Yang ◽  
Christopher Daniel Chien ◽  
Elad Jacoby ◽  
Haiying Qin ◽  
Waleed Haso ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Ifn Gamma ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T Cell Therapy ◽  
Car T

Abstract Adoptive therapy using T cells genetically engineered to express chimeric antigen receptors (CAR) has proven extremely effective against acute lymphoblastic leukemia (ALL) in clinical trials with the use of anti-CD19 CAR T cells. Most CAR T cell protocols use autologous T cells, which are then activated, transduced with the anti-CD19 CAR, and expanded ex-vivo before infusion back into the patient. This approach minimizes the risk of graft-versus-host disease (GVHD) even in allogeneic transplant recipients, due to tolerization of the donor T cell repertoire in the recipient. However, many patients have heavy disease burden and lymphopenia due to previous treatments, which makes the isolation of healthy T cells difficult. Thus, centers are exploring the potential of allogeneic T cell donors and the possibility of universal T cell donors for CAR-based therapy including the use of virus-specific T cells. In these cases, in addition to the chimeric receptor specificity, the transduced T cell population will also have reactivity against target antigens through the endogenous TCR. However, little is known about the impact of signaling of the endogenous TCR on CAR T cell activity, particularly in vivo. To test this, we used a syngeneic transplantable ALL murine model, E2aPBx, in which CD19 CAR T cells can effectively eradicate ALL. CD4 (Marilyn) and CD8 (Matahari) T cells from syngeneic HY-TCR transgenic donors specific for the minor histocompatibility male antigen, HY, were used as CAR T cell donors to control for endogenous TCR reactivity. Splenic T cells isolated from Matahari, Marilyn, or B6 mice were activated ex-vivo using anti-CD3/anti-CD28 beads, with the addition of IL2 and IL7. T cells were transduced with a retroviral vector expressing a murine CAR composed of anti-CD19 scfv/CD28/CD3ζ on days two and three. CAR T cells are evaluated in vitro by CD107a degranulation assay and INF gamma ELISA. In response to HY peptide alone or HY+CD19- line M39M, transduced CD8 HY (Matahari) cells produced IFN gamma and expressed CD107a whereas transduced CD4 HY (Marilyn) cells only produced IFN gamma. Interestingly, in response to CD19+HY- ALL, both Matahari and Marilyn expressed CD107a and produced IFN gamma indicating that CD4 T cells can acquire CD8-like lytic activity when stimulated through a CAR receptor. When CD19 CAR transduced Marilyns and Mataharis were stimulated in the presence of HY and CD19, CD8 Mataharis had an attenuated effect against CD19, suggesting that the presence of antigen activated TCR adversely affects the potency of the CAR receptor. Efficacy of the HY and polyclonal CAR T cells were next tested in-vivo in male and female B6 mice. Mice were given 1E6 E2aPBx ALL leukemia cells on day 1, and received 500 rads sub-lethal total body irradiation on day 4 as a lymphodepleting regimen. On day 5, mice were given a low (1E5) or high (5E6) dose of CAR T cells. There was a statistically significant (p=0.0177) improvement in the survival of female versus male mice after treatment with the CD4+ HY specific anti-CD19 CAR T cells, and female mice that received HY anti-CD19 CAR T cells survived longer than untreated control females (p=0.01). Remarkably, the survival of male mice that received HY anti-CD19 CAR T cells was statistically worse than untreated control males (p=0.008). This suggests that the presence of TCR antigen negatively impacts the function of CAR T cells. Furthermore, in a separate experiment using an equally mixed population of Marilyn (CD4+) and Matahari (CD8+) HY specific T cells, males has a statistically significantly (p=0.0116) worse survival compared to females after receiving 5E5 HY specific T cells. In conclusion, simultaneous stimulation through both CAR and TCR results in attenuated cytokine production and degranulation by CD8 T cells. In vivo, in the presence of the endogenous TCR antigen, both CD4 and CD8 CAR T cells are less potent at eradicating leukemia. These have implications for the development of universal donors for CAR T cell therapy. Disclosures No relevant conflicts of interest to declare.

Updated results from ZUMA-3, a phase 1/2 study of KTE-C19 chimeric antigen receptor (CAR) T cell therapy, in adults with high-burden relapsed/refractory acute lymphoblastic leukemia (R/R ALL).

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 3024-3024 ◽  
Author(s):  
Bijal D. Shah ◽  
William G. Wierda ◽  
Gary J. Schiller ◽  
Michael Russell Bishop ◽  
Januario E. Castro ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Therapy ◽  
Disease Burden ◽  
Phase 1 ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T Cell Therapy ◽  
Car T

3024 Background: Promising results have been observed with KTE-C19, an anti-CD19 CAR T cell therapy, in refractory aggressive NHL in the ZUMA-1 trial (Blood 2016;128:LBA-6). We present here updated results from the ZUMA-3 phase 1 trial of KTE-C19 in adult patients (pts) with R/R ALL. Methods: Adult (≥18 y) pts with R/R ALL (Ph+ eligible), ≥25% bone marrow (BM) blasts, adequate organ function and ECOG status 0-1 received 1 or 2×106 CAR T cells/kg after conditioning with cyclophosphamide + fludarabine. Phase 1 primary endpoint is incidence of dose-limiting toxicity (DLT). Secondary endpoints include efficacy outcomes and biomarker associations. Results: As of Nov 1, 2016, 11 pts were enrolled; 10 received KTE-C19. One pt had a serious adverse event (SAE) prior to dosing and was not treated. KTE-C19 was successfully manufactured in all pts across a broad range of baseline absolute lymphocyte counts in 6 days in a centralized facility, with an approximate 2-week turnaround time. Pts were 60% men with 1-4 prior lines of therapy and high disease burden (median, 70% BM blasts). No pt (0/3) experienced a DLT at the 2×106 dose. Phase 1 was expanded to 6 pts at the same dose; 1 grade (Gr) 5 AE (multiorgan failure due to cytokine release syndrome [CRS]) was observed. Subsequent pts (4) received 1×106 CAR T cells/kg. Overall, the most common Gr≥3 AEs were cytopenias (80%), febrile neutropenia (50%), pyrexia (40%), and transaminitis (40%). Gr≥3 CRS and neurologic events (NEs) were reported in 20% and 40% of pts, respectively. Cerebral edema was not observed. All CRS (except Gr5) and 5 of 6 NEs (1 Gr3 ongoing at cut-off) resolved. Of the 8 efficacy evaluable pts, 6 achieved an MRD-negative (MRD–) complete response (CR, or CR + partial or incomplete hematopoietic recovery). Updated results will include additional pt follow-up and biomarker data. Conclusions: No DLTs were observed with KTE-C19 in adult pts with high BM disease burden; one pt had G5 CRS after the DLT cohort. Manufacturing was successful in all pts; most pts achieved an MRD– CR. Based on these results, ZUMA-3 continues to enroll pts with additional measures implemented to further enhance safety. Clinical trial information: NCT02614066.

scholarly journals Adult Patients with ALL Treated with CD62L+ T Naïve/Memory-Enriched T Cells Expressing a CD19-CAR Mediate Potent Antitumor Activity with a Low Toxicity Profile

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4016-4016 ◽  
Author(s):  
Samer K. Khaled ◽  
Suzette Blanchard ◽  
Xiuli Wang ◽  
Jamie Wagner ◽  
Araceli Naranjo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Research Funding ◽  
Disease Burden ◽  
Phase 1 ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T ◽  
Manufacturing Platform ◽  
Grade 3

Abstract Introduction: Treatment of adults with relapsed/refractory (R/R) B-ALL using CD19-targeted chimeric antigen receptor (CAR) T cells has achieved remarkable remission rates, both in pediatric and adult populations. There are multiple CAR constructs and T cell manufacturing platforms in use, and both aspects of the therapy may impact efficacy and toxicity. Park et al. report that 83% of adult patients (pts) achieve complete response (CR) to their CD19 CAR T cells with a CD28 costimulatory domain (NEJM; 3785: 449), using an unselected peripheral blood (PBMC) manufacturing platform. Unfortunately, therapy-associated toxicities in adult and pediatric ALL pts are problematic, with grade 3/4 cytokine release syndrome (CRS) ranging from 26-49 % and neurotoxicity 18-42%. Here we report preliminary data from one arm of a phase 1 clinical trial (NCT02146924) in adult pts with R/R B-ALL testing a memory-enriched T cell starting population engineered to express a CD19-specific, CD28-costimulatory CAR (CD19:28z-CAR). All pts achieved CR or CRi with a low incidence of severe cytokine release syndrome (CRS) and neurotoxicity. Unique to this study is our Tn/mem-enriched manufacturing platform, a naïve/memory T cell-enriched T cell product that is lentivirally transduced to express our CD19:28z-CAR. The manufacturing process starts with patient PBMC, depletes the CD14+ monocytes and CD25+ Tregs, and selects for CD62L+ T cells. The resultant T cell population for CAR transduction includes both the central memory and stem cell memory populations along with naïve T cells. Preclinical studies in mice had suggested that using a more uniform T cell product with a less-differentiated T cell phenotype improved antitumor activity. This Tn/mem manufacturing platform is the same as our Tcm-derived platform (Blood;127:2980) except that CD45RA depletion was omitted. Patients and Methods: This phase I study used the activity constrained for toxicity (ACT) design, an extension of the toxicity equivalence range (TEQR) design of Blanchard and Longmate (Contemp Clin Trials; 32:114), that dose escalates based on lack of activity, while constraining the dose for toxicity. The primary objectives of this study were to test the safety and activity of Tn/mem-enriched CD19:28z CAR T cells, and to determine the phase 2 recommended dose. The primary endpoints were toxicity and disease response. Sixteen pts were consented and received a lymphodepleting regimen (LDR) of 1.5-3 gm/m2 cyclophosphamide over 2-3 days and 25-30 mg/m2 fludarabine for 3 days. Three pts received LDR, but did not receive T cells due to infection or lack of CD19+ disease. Patients received a flat dose of 200 million (M) CD19:28z-CAR T cells: 11 autologous and 2 allogeneic donor products. Of the 13 that received 200 M CAR+ T cells, 2 pts were deemed ineligible for dose escalation / disease response evaluation, as 1 received <80% of the prescribed dose (100 M) and the other had CD19-negative extramedullary disease. The median age of the 13 CAR T cell treated pts was 33 years (24-72). All pts had active bone marrow (BM) disease at the time of LDR: 8 pts (62%) had high disease burden (15-91% BM blasts) and 5 had low disease burden (</= 5% BM blasts). Patients were heavily pretreated, with a median of 5 (2-6), prior regimens. Six pts received prior allogeneic transplant (HSCT), 9 had prior blinatumomab, and 1 had prior CD19 CAR T cells. Results: Toxicity: Table 1 describes the major toxicities of the 13 CAR-treated pts, stratified based on disease burden. There were no DLTs, and T-cell therapy attributed (>/=possibly) toxicities were typically mild and reversible. Eight pts had grade 2 CRS, and 2 had grade 3 CRS. Three pts had grade 2 neurotoxicity and 2 had grade 3. Response: Eleven pts were evaluable for response, with best response of 4 CRs (MRD- by flow) and 7 CRi (6 MRD-, 1 not tested). Median response duration at last contact or HSCT start was 81 days (39-286); 8 pts proceeded to HSCT (in CR or CRi) at a median of 69 days post-CAR infusion (39-103). Conclusions: Our ongoing phase 1 trial demonstrates a 100% response rate to Tn/mem-enriched CD19:28z-CAR T cell therapy in adults with relapsed/refractory (R/R) B-ALL. Although the numbers are small, the unanimous response, combined with a tolerable and reversible toxicity profile in pts with both low and high disease burden is remarkable and suggests promise for this Tn/mem manufacturing platform for CD19 and other CAR targets. Disclosures Khaled: Juno: Other: Travel Funding; Daiichi: Consultancy; Alexion: Consultancy, Speakers Bureau. Wang:Mustang Therapeutics: Other: Licensing Agreement, Patents & Royalties, Research Funding. Brown:Mustang Therapeutics: Consultancy, Other: Licensing Agreement, Patents & Royalties, Research Funding. Forman:Mustang Therapeutics: Other: Licensing Agreement, Patents & Royalties, Research Funding.

Phase 1 Study of CART-ddBCMA, a CAR-T therapy utilizing a novel synthetic binding domain, for the treatment of subjects with relapsed and refractory multiple myeloma.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 8015-8015
Author(s):  
Matthew J. Frigault ◽  
Elizabeth O'Donnell ◽  
Noopur S. Raje ◽  
Daniella Cook ◽  
Andrew Yee ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
High Risk ◽  
T Cell Activation ◽  
Phase 1 ◽  
Binding Domain ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T

8015 Background: CART-ddBCMA is an autologous CAR-T cell therapy encoding a novel non-scFv synthetic binding domain targeting BCMA with a 4-1BB costimulatory motif and CD3-zeta T-cell activation domain. The novel binding domain is based on a computationally-derived triple-helix protein scaffold that is small (73 amino acids), stable, engineered to reduce immunogenicity, and can be modified to bind alternative targets. Methods: ARC-101 (NCT04155749), ARM 1 (CART-ddBCMA) is a Phase 1, multi-center, open-label, dose escalation trial enrolling subjects who have received ≥3 prior regimens, including proteasome inhibitor(s), immuno-modulatory agent(s), and anti-CD38 antibody, or are triple-refractory. Subjects undergo lymphodepletion with fludarabine and cyclophosphamide, then receive CART-ddBCMA as a single infusion. Planned dose levels are 100, 300, and up to 900 x 106 CAR+ T cells. The primary endpoint is incidence of adverse events (AEs), including dose-limiting toxicities (DLTs). Secondary endpoints include clinical response per IMWG criteria, MRD, DOR, PFS, OS, and CAR-T cell kinetics. Results: As of 29 Jan 2021, 10 subjects received CART-ddBCMA, 9 subjects were evaluable, and 1 subject was pending assessment. Median age was 66 years [min:max 54 to 75]. 6 subjects received 100 x 106 CAR+ T cells, and 4 subjects received 300 x 106 CAR+ T cells. Median CAR+ expression was 74.5% (min:max 61-87%) of total T cells. Of the evaluable subjects, median follow-up after cell infusion was 208 days (min:max 45 to 355+ days), 9/9 subjects were penta-refractory, 1 subject was also refractory to BCMA-directed ADC. 8/9 had high-risk cytogenetics (1 subject’s sample not evaluable), and 6/9 subjects had extramedullary disease. No DLTs were reported. Per ASTCT Consensus Grading (Lee et al, 2019), 8 subjects developed G1/2 CRS, 1 subject in the higher dose cohort developed G3 CRS that rapidly resolved with tocilizumab. 1 subject developed G2 ICANS which rapidly resolved with intervention. 7 subjects received tocilizumab; 3 received dexamethasone. ORR was 100% (9/9) per IMWG criteria including 4 sCR, 1 VGPR, and 4 PR. 1 subject with PR relapsed and was retreated. All other subjects have ongoing responses; observations included sFLC normalization and elimination of detectable bone marrow disease by Month 1. Ongoing responses for subjects not yet achieving CR continue to deepen. 7 subjects were evaluable by MRD of which 5 are MRD-negative, and 2 are pending results. CAR-T cell expansion, as measured by vector transgene copies per microgram genomic DNA was observed in all patients. Conclusions: Early efficacy results are encouraging, with 9/9 (100%) ORR and manageable toxicities. 8/9 responses are ongoing and responses continue to deepen. These data are encouraging in high-risk subjects with penta-refractory myeloma. Subjects continue to be enrolled and treated. Clinical trial information: NCT04155749.

scholarly journals IMMU-12. IL13Ra2-CAR T CELLS STIMULATE ENDOGENOUS IMMUNE RESPONSES AGAINST MURINE GLIOBLASTOMAS

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi121-vi121
Author(s):  
Darya Alizadeh ◽  
Robyn Wong ◽  
Joseph Pecoraro ◽  
Xin Yang ◽  
Stephen Forman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antitumor Activity ◽  
Cell Therapy ◽  
Immune Responses ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell Therapy ◽  
Car T

Abstract Malignant gliomas (MG) are one of the deadliest cancers with very limited therapeutic options. Chimeric antigen receptor (CAR)-T cell therapy has emerged as a powerful strategy for B-cell malignancies and may offer new opportunities to improve outcomes for patients with MGs. Our team is clinically evaluating IL13Rα2-targeted CAR-T cells for the treatment of recurrent IL13Rα2-positive MGs [NCT02208362]. While this trial is ongoing, we have previously reported that one patient with recurrent multifocal glioblastoma achieved a complete response post-IL13Rα2-CAR-T therapy despite the non-uniform expression of IL13Rα2 on the tumor. The therapeutic response against IL13Rα2-negative cells suggests CAR-T cells may stimulate endogenous immune responses. To study the interplay between CAR-T cells and host immune subsets, we have established a syngeneic immunocompetent glioma model, which recapitulates the tumor microenvironment (TME) of patients. Murine IL13Rα2-CAR-T cells mediate potent antitumor activity against IL13Rα2-engineered KR158, a highly invasive murine glioma model. Interestingly, mice “cured” from CAR-T therapy, after rechallenge, can successfully reject the tumors. Furthermore, we demonstrate comparable response rate in mice bearing gliomas with mixed antigen expression (50%IL13Rα2+/50%IL13Rα2-) vs 100% IL13Rα2+. Characterization of the TME post-CAR-T therapy indicates activation of endogenous cytotoxic CD8 T and myeloid cells, and decrease in the frequency of T regulatory cells. Further analyses reveal that tumor-associated macrophages (TAMs) may be reprogrammed during CAR-T therapy to exhibit tumoricidal activity and may promote the activation of endogenous T cells (CD4/CD8 T cells) resulting in enhanced antitumor activity. Current studies are focusing on the characterization of host immune cells to identify the mechanisms involved in induction of host immune responses mediated by CAR-T cell therapy. Our data thus strongly suggest that CAR-T therapy has the potential to reshape the glioma microenvironment creating a context permissible to elicit effective endogenous antitumor immunity.

scholarly journals 4-1BB costimulation promotes CAR T cell survival through noncanonical NF-κB signaling

2020 ◽  
Vol 13 (625) ◽  
pp. eaay8248 ◽  
Author(s):  
Benjamin I. Philipson ◽  
Roddy S. O’Connor ◽  
Michael J. May ◽  
Carl H. June ◽  
Steven M. Albelda ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Free Ligand ◽  
Hematologic Malignancies ◽  
Nuclear Factor Κb ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T

Clinical response to chimeric antigen receptor (CAR) T cell therapy is correlated with CAR T cell persistence, especially for CAR T cells that target CD19+ hematologic malignancies. 4-1BB–costimulated CAR (BBζ) T cells exhibit longer persistence after adoptive transfer than do CD28-costimulated CAR (28ζ) T cells. 4-1BB signaling improves T cell persistence even in the context of 28ζ CAR activation, which indicates distinct prosurvival signals mediated by the 4-1BB cytoplasmic domain. To specifically study signal transduction by CARs, we developed a cell-free, ligand-based activation and ex vivo culture system for CD19-specific CAR T cells. We observed greater ex vivo survival and subsequent expansion of BBζ CAR T cells when compared to 28ζ CAR T cells. We showed that only BBζ CARs activated noncanonical nuclear factor κB (ncNF-κB) signaling in T cells basally and that the anti-CD19 BBζ CAR further enhanced ncNF-κB signaling after ligand engagement. Reducing ncNF-κB signaling reduced the expansion and survival of anti-CD19 BBζ T cells and was associated with a substantial increase in the abundance of the most pro-apoptotic isoforms of Bim. Although our findings do not exclude the importance of other signaling differences between BBζ and 28ζ CARs, they demonstrate the necessary and nonredundant role of ncNF-κB signaling in promoting the survival of BBζ CAR T cells, which likely underlies the engraftment persistence observed with this CAR design.

scholarly journals Switch receptor T3/28 improves long-term persistence and antitumor efficacy of CAR-T cells

2021 ◽  
Vol 9 (12) ◽  
pp. e003176
Author(s):  
Songbo Zhao ◽  
Chunhua Wang ◽  
Ping Lu ◽  
Yalin Lou ◽  
Huimin Liu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antitumor Activity ◽  
Lymphoid Leukemia ◽  
T Cell Therapy ◽  
Cell Therapies ◽  
Car T Cells ◽  
Car T

BackgroundChimeric antigen receptor (CAR) T cells have been successfully used in tumor immunotherapy due to their strong antitumor responses, especially in hematological malignancies such as B cell acute lymphoid leukemia. However, on-target off-tumor toxicity and poor persistence severely limit the clinical application of CAR-T cell therapy.MethodsT-cell immunoglobulin mucin domain molecule 3 (TIM-3) was used to develop a second-generation 41BB CD19 CAR linked with a T3/28 chimera, in which truncated extracellular TIM-3 was fused with the CD28 transmembrane and cytoplasmic domains. The efficacy of T3/28 CAR-T cells was evaluated in vitro and in vivo.ResultsWe demonstrated that the switch receptor T3/28 preserved the TCM phenotype, improved proliferative capacity, and reduced exhaustion of CAR-T cells, resulting in superior in vitro and in vivo antitumor activity in B lymphoma. Importantly, the switch receptor T3/28 substantially prolonged the persistence of CAR-T cells, and the interleukin-21/Stat3 axis probably contributed to the enhanced cytotoxicity of T3/28 CAR-T cells.ConclusionOverall, the T3/28 chimera significantly prolonged the persistence of CAR-T cells, and T3/28 CAR-T cells possessed potent antitumor activity in mice, shedding new light on potential improvements in adoptive T cell therapies.

scholarly journals A Bispecific CAR-T Cell Therapy Targeting Bcma and CD38 for Relapsed/Refractory Multiple Myeloma: Updated Results from a Phase 1 Dose-Climbing Trial

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 930-930 ◽  
Author(s):  
Chenggong Li ◽  
Heng Mei ◽  
Yu Hu ◽  
Tao Guo ◽  
Lin Liu ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
T Cells ◽  
T Cell ◽  
Cell Therapy ◽  
Phase 1 ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T Cell Therapy ◽  
Car T

Background: Anti-B cell maturation antigen (BCMA) chimeric antigen receptor(CAR) T cell therapy has shown promising results from a series of clinical trials. But short progression-free survival (PFS) due to BCMA-negative or positive relapse is pretty much the agenda.Here we constructed a dual-target BM38 CAR incorporating the anti-CD38 and anti-BCMA single-chain variable fragment in tandem plus 4-1BB signaling and CD3 zeta domains and conducted the first-in-human clinical trial(ChiCTR1800018143) in patients with RRMM to evaluate the safety, efficacy and duration of BM38 T cells. Methods:Patients with relapsed or refractory multiple myeloma(RRMM), who had received at least 2 prior treatment regimens, including a proteasome inhibitor and an immunomodulatory agent, were enrolled in the phase 1 dose-climbing trial of the bispecific CAR-T cell therapy. Patients were subjected to a lymphodepleting regimen with Cy(250 mg/m2, d-5 to d-3) and Flu(25 mg/m2, d-5 to d-3) daily prior to the CAR-T infusion (d0). The dose gradients of infused CAR-T cells were 0.5, 1.0, 2.0, 3.0 and 4.0×106 cells/kg and at least 2 patients were involved at every dose level. The efficacy was assessed by the International Uniform Response Criteria for Multiple Myeloma (2016), and the toxicity was graded by CTCAE 5.0. Results: As of 31 July 2019, 16 pts consisting of 10(62.5%) with genetic abnormalities and 5(31.25%) with extramedullary lesions,had received BM38 CAR-T cells in the 5 dose-climbing cohorts. At a median follow-up of 36 weeks, no DLTs and no grade ≥ 3 neurotoxicities were observed. Cytokine release syndrome (CRS), mainly grade 1-2, was reported in 10 of 16 (62.5%) pts; 4 pts had grade ≥ 3 CRS that resolved by tocilizumab and supportive treatment. Almost all the pts were observed with hematological toxicities relieved in the first month after infusion.14(87.5%) pts achieved an overall response with 8(50%) sCR, 2(12.5%) VGPR and 4(25.00%) PR and 14(87.5%) reached bone marrow minimal residual disease(MRD)-negative status. The longest duration of sCR was over 51 weeks and 5(62.5%) of 8 patients had still maintained sCR and 2 transformed to VGPR and 1 to PR. The median duration of progression-free survival(PFS) had not been reached; PFS rates at 9 months was 75%. More encouragingly, 5(100%)extramedullary lesions were eliminated.Up to the observed day, the BM38 CAR-T cells still exist in the patients' peripheral blood by flow cytometry(FCM) and quantitative polymerase chain reaction(q-PCR). The peak time of CAR-T cells proliferation of sCR patients was about the 2nd week after infusion, which was earlier than other patients. 4.0 × 106 CAR T cells (pt11, 12 and 15) were selected for the optimal dose with superior response and acceptable toxicities and expansion cohort would be conducted. Conclusions:Our study demonstrates an improved efficacy with the bivalent BM38 CAR-T therapy for RRMM with a high ORR, especially a higher rate and a longer duration of sCR and effective elimination for extramedullary lesions. No neurotoxicity was observed. CRS and other toxicities were manageable. These initial data provide strong evidence to support the further development of the dual-target CAR-T therapy for RRMM. Clinical trial information: ChiCTR1800018143 Disclosures No relevant conflicts of interest to declare.

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