Signaling via a CD27-TRAF2-SHP-1 axis during naive T cell activation promotes memory-associated gene regulatory networks.

The interaction of the tumor necrosis factor receptor (TNFR) family member CD27 on naive CD8+ T (Tn) cells with homotrimeric CD70 on antigen-presenting cells (APCs) is necessary for T cell memory fate determination. Here, we examined CD27 signaling during Tn cell activation and differentiation. In conjunction with T cell receptor (TCR) stimulation, ligation of CD27 by a synthetic trimeric CD70 ligand triggered CD27 internalization and degradation, suggesting active regulation of this signaling axis. Internalized CD27 recruited the signaling adaptor TRAF2 and the phosphatase SHP-1, thereby modulating TCR and CD28 signals. CD27-mediated modulation of TCR signals promoted transcription factor circuits that induced memory rather than effector associated gene programs, which are induced by CD28 costimulation. CD27-costimulated chimeric antigen receptor (CAR)-engineered T cells exhibited improved tumor control compared with CD28-costimulated CAR-T cells. Thus, CD27 signaling during Tn cell activation promotes memory properties with relevance to T cell immunotherapy.

Tumor Interferon Signaling Is Regulated by a lncRNA INCR1 Transcribed from the PD-L1 Locus.

Tumor interferon (IFN) signaling promotes PD-L1 expression to suppress T cell-mediated immunosurveillance. We identify the IFN-stimulated non-coding RNA 1 (INCR1) as a long noncoding RNA (lncRNA) transcribed from the PD-L1 locus and show that INCR1 controls IFNγ signaling in multiple tumor types. Silencing INCR1 decreases the expression of PD-L1, JAK2, and several other IFNγ-stimulated genes. INCR1 knockdown sensitizes tumor cells to cytotoxic T cell-mediated killing, improving CAR T cell therapy. We discover that PD-L1 and JAK2 transcripts are negatively regulated by binding to HNRNPH1, a nuclear ribonucleoprotein. The primary transcript of INCR1 binds HNRNPH1 to block its inhibitory effects on the neighboring genes PD-L1 and JAK2, enabling their expression. These findings introduce a mechanism of tumor IFNγ signaling regulation mediated by the lncRNA INCR1 and suggest a therapeutic target for cancer immunotherapy.

Beyond youth: Understanding CAR T cell fitness in the context of immunological aging.

Population aging, a pervasive global demographic trend, is anticipated to challenge health and social systems worldwide. This phenomenon is due to medical advancements enabling longer lifespans, with 20% of the US population soon to be over 65 years old. Consequently, there will be a surge in age-related diseases. Senescence, characterized by the loss of biological maintenance and homeostasis at molecular and cellular levels, either correlates with or directly causes age-related phenotypic changes. Decline of the immune system is a critical factor in the senescence process, with cancer being a primary cause of death in elderly populations. Chimeric antigen receptor (CAR) T cell therapy, an innovative approach, has demonstrated success mainly in pediatric and young adult hematological malignancies but remains largely ineffective for diseases affecting older populations, such as late-in-life B cell malignancies and most solid tumor indications. This limitation arises because CAR T cell efficacy heavily relies on the fitness of the patient-derived starting T cell material. Numerous studies suggest that T cell senescence may be a key driver of CAR T cell deficiency. This review examines correlates and underlying factors associated with favorable CAR T cell outcomes and explores potential experimental and clinically actionable strategies for T cell rejuvenation.

Charging CAR by electrostatic power.

Chimeric antigen receptor (CAR)-T cell therapy has emerged as a promising approach for cancer treatment. CAR is a synthetic immune receptor that recognizes tumor antigen and activates T cells through multiple signaling pathways. However, the current CAR design is not as robust as T cell receptor (TCR), a natural antigen receptor with high sensitivity and efficiency. TCR signaling relies on specific molecular interactions, and thus electrostatic force, the major force of molecular interactions, play critical roles. Understanding how electrostatic charge regulates TCR/CAR signaling events will facilitate the development of next-generation T cell therapies. This review summarizes recent findings on the roles of electrostatic interactions in both natural and synthetic immune receptor signaling, specifically that in CAR clustering and effector molecule recruitments, and highlights potential strategies for engineering CAR-T cell therapy by leveraging charge-based interactions.

New Biological Therapies for Multiple Myeloma.

Multiple myeloma is a cancer of bone marrow plasma cells that represents approximately 10% of hematologic malignancies. Though it is typically incurable, a remarkable suite of new therapies developed over the last 25 years has enabled durable disease control in most patients. This article briefly introduces the clinical features of multiple myeloma and aspects of multiple myeloma biology that modern therapies exploit. Key current and emerging treatment modalities are then reviewed, including cereblon-modulating agents, proteasome inhibitors, monoclonal antibodies, other molecularly targeted therapies (selinexor, venetoclax), chimeric antigen receptor T cells, T cell-engaging bispecific antibodies, and antibody-drug conjugates. For each modality, mechanism of action and clinical considerations are discussed. These therapies are combined and sequenced in modern treatment pathways, discussed at the conclusion of the article, which have led to substantial improvements in outcomes for multiple myeloma patients in recent years.

Trends in cell medicine: from autologous cells to allogeneic universal-use cells for adoptive T-cell therapies.

In currently ongoing adoptive T-cell therapies, T cells collected from patients are given back to them after ex vivo activation and expansion. In some cases, T cells are transduced with chimeric antigen receptor (CAR) or T-cell receptor (TCR) genes during the ex vivo culture period in order to endow T cells with the desired antigen specificity. Although such strategies are effective in some types of cancer, there remain issues to be solved: (i) the limited number of cells, (ii) it is time-consuming, (iii) it is costly, and (iv) the quality can be unstable. Points (ii) and (iv) can be solved by preparing allogeneic T cells and cryopreserving them in advance and methods are being developed using healthy donor-derived T cells or pluripotent stem cells as materials. Whereas it is difficult to solve (i) and (iii) in the former case, all the issues can be cleared in the latter case. However, in either case, a new problem arises: rejection by the patient's immune system. Deletion of human leukocyte antigen (HLA) avoids rejection by recipient T cells, but causes rejection by NK cells, which can recognize loss of HLA class I. Various countermeasures have been developed, but no definitive solution is yet available. Therefore, further research and development are necessary.

High CD62L expression predicts the generation of chimeric antigen receptor T cells with potent effector functions.

The efficient generation of chimeric antigen receptor (CAR) T cells is highly influenced by the quality of apheresed T cells. Healthy donor-derived T cells usually proliferate better than patients-derived T cells and are precious resources to generate off-the-shelf CAR-T cells. However, relatively little is known about the determinants that affect the efficient generation of CAR-T cells from healthy donor-derived peripheral blood mononuclear cells (PBMCs) compared with those from the patients' own PBMCs. We here examined the efficiency of CAR-T cell generation from multiple healthy donor samples and analyzed its association with the phenotypic features of the starting peripheral blood T cells. We found that CD62L expression levels within CD8+ T cells were significantly correlated with CAR-T cell expansion. Moreover, high CD62L expression within naïve T cells was associated with the efficient expansion of T cells with a stem cell-like memory phenotype, an indicator of high-quality infusion products. Intriguingly, genetic disruption of CD62L significantly impaired CAR-T cell proliferation and cytokine production upon antigen stimulation. Conversely, ectopic expression of a shedding-resistant CD62L mutant augmented CAR-T cell effector functions compared to unmodified CAR-T cells, resulting in improved antitumor activity in vivo. Collectively, we identified the surface expression of CD62L as a concise indicator of potent T-cell proliferation. CD62L expression is also associated with the functional properties of CAR-T cells. These findings are potentially applicable to selecting optimal donors to massively generate CAR-T cell products.

High-multiplex single-cell imaging analysis reveals tumor immune contexture associated with clinical outcomes after CAR T cell therapy.

Chimeric antigen receptor (CAR) T cell therapy has made great progress in treating lymphoma, yet patient outcomes still vary greatly. The lymphoma microenvironment may be an important factor in the efficacy of CAR T therapy. In this study, we designed a highly multiplexed imaging mass cytometry (IMC) panel to simultaneously quantify 31 biomarkers from 13 patients with relapsed/refractory diffuse large B cell lymphoma (DLBCL) who received CAR19/22 T cell therapy. A total of 20 sections were sampled before CAR T cell infusion or after infusion when relapse occurred. A total of 35 cell clusters were identified, annotated, and subsequently redefined into 10 metaclusters. The CD4+ T cell fraction was positively associated with remission duration. Significantly higher Ki67, CD57, and TIM3 levels and lower CD69 levels in T cells, especially the CD8+/CD4+ Tem and Te cell subsets, were seen in patients with poor outcomes. Cellular neighborhood containing more immune cells was associated with longer remission. Fibroblasts and vascular endothelial cells resided much closer to tumor cells in patients with poor response and short remission after CAR T therapy. Our work comprehensively and systematically dissects the relationship between cell composition, state, and spatial arrangement in the DLBCL microenvironment and the outcomes of CAR T cell therapy, which is beneficial to predict CAR T therapy efficacy.

Intrinsic ADRB2 inhibition improves CAR-T cell therapy efficacy against prostate cancer.

Chimeric antigen receptor (CAR)-T cell therapy has shown limited success in patients with solid tumors. Recent in vitro and in vivo data have shown that adrenoceptor beta-2 (ADRB2) is a novel checkpoint receptor that inhibits T cell-mediated anti-tumor responses. To inhibit ADRB2-mediated inhibitory signaling, we downregulated ADRB2 in CAR-T (shß2-CAR-T) cells via RNA interference, assessed different parameters, and compared them with conventional second-generation CAR-T cells. ADRB2 knockdown CAR-T cells exhibited enhanced cytotoxicity against prostate cancer cell lines in vitro, by increasing CD69, CD107a, GzmB, IFN-γ, T-bet, and GLUT-1. In addition, ADRB2 deficiency led to improved proliferation, increased CD8/CD4 T cell ratio, and decreased apoptosis in CAR-T cells. shß2-CAR-T cells expressed more Bcl-2 and led to the generation of more significant proportions of T central memory cells. Finally, the ZAP-70/NF-κB signaling axis was shown to be responsible for the improved functions of novel CAR-T cells. In tumor-bearing mice, shß2-CAR-T cells performed better than conventional CAR-T cells in eradicating prostate tumors. The study provides the basis for future clinical and translational CAR-T cell research to focus on adrenergic stress-mediated challenges in the tumor microenvironment of stressed tumors.

Outcomes in Hematopoietic Cell Transplant and Chimeric Antigen Receptor T-Cell Therapy Recipients With Pre-Cellular Therapy SARS-CoV-2 Infection.

BACKGROUND: Hematopoietic cell transplant (HCT) or chimeric antigen receptor (CAR) T-cell therapy recipients have high morbidity from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. There are limited data on outcomes from SARS-CoV-2 infection shortly before cellular therapy and uncertainty whether to delay therapy. METHODS: We conducted a retrospective cohort study of patients with SARS-CoV-2 infection within 90 days before HCT or CAR-T-cell therapy between January 2020 and November 2022. We characterized the kinetics of SARS-CoV-2 detection, clinical outcomes following cellular therapy, and impact on delays in cellular therapy. RESULTS: We identified 37 patients (n = 15 allogeneic HCT, n = 11 autologous HCT, n = 11 CAR-T-cell therapy) with SARS-CoV-2 infections within 90 days of cellular therapy. Most infections (73%) occurred between March and November 2022, when Omicron strains were prevalent. Most patients had asymptomatic (27%) or mild (68%) coronavirus disease 2019 (COVID-19). SARS-CoV-2 positivity lasted a median of 20.0 days (interquartile range, 12.5-26.25 days). The median time from first positive SARS-CoV-2 test to cellular therapy was 45 days (interquartile range, 37.75-70 days); 1 patient tested positive on the day of infusion. After cellular therapy, no patients had recrudescent SARS-CoV-2 infection or COVID-19-related complications. Cellular therapy delays related to SARS-CoV-2 infection occurred in 70% of patients for a median of 37 days. Delays were more common after allogeneic (73%) and autologous (91%) HCT compared to CAR-T-cell therapy (45%). CONCLUSIONS: Patients with asymptomatic or mild COVID-19 may not require prolonged delays in cellular therapy in the context of contemporary circulating variants and availability of antiviral therapies.

Coagulopathy in CAR-T: Critical concern or mere blip?

Despite Peng and colleagues providing an extensive review of the clinical and laboratory aspects of CAR-T-associated coagulopathy, the current literature often lacks specificity in nomenclature and gradings, and the clinical implications of coagulopathy may remain unclear. Clear recommendations on stratification and prophylaxis are still required to standardize the clinical approach to this topic. Commentary on: Peng et al. Coagulation abnormalities associated with CAR-T therapy in hematological malignancies: A review. Br J Haematol 2024;205:420-428.

Serum mass spectrometry for treatment monitoring in patients with multiple myeloma receiving ARI0002h CAR T-cells.

Chimeric antigen receptor (CAR) T-cell therapies have increased the patients with relapsed/refractory multiple myeloma (RRMM) in whom standard electrophoretic techniques fail to detect the M-protein. Quantitative immunoprecipitation mass spectrometry (QIP-MS) can accurately measure serum M-protein with high sensitivity, and identify interferences caused by therapeutic monoclonal antibodies. Here, we investigate the outcome of QIP-MS in 33 patients treated with the academic BCMA-directed CAR T-cell ARI0002h (Cesnicabtagene Autoleucel). QIP-MS offered more detailed insights than serum immunofixation (sIFE), identifying glycosylated M-proteins and minor additional peaks. Moreover, the potential interferences owing to daratumumab or tocilizumab treatments were successfully detected. When analysing different assay platforms during patient's monitoring after ARI0002h administration, we observed that QIP-MS showed a high global concordance (78.8%) with sIFE, whereas it was only moderate (55.6%) with bone marrow (BM)-based next-generation flow cytometry (NGF). Furthermore, QIP-MS consistently demonstrated the lowest negativity rate across the different timepoints (27.3% vs. 60.0% in months 1 and 12, respectively). Patients with QIP-MS(+)/BM-based NGF(-) showed a non-significant shorter median progression free survival than those with QIP-MS(-)/BM-based NGF(-). In summary, we show the first experience to our knowledge demonstrating that QIP-MS could be particularly useful as a non-invasive technique when evaluating response after CAR T-cell treatment in MM.

Sequence not salvage.

Chimeric antigen receptor T-cell (CAR-T) therapy for the treatment of multiple myeloma (MM) has fundamentally changed the relapsed and refractory therapeutic landscape, but the disease remains incurable. Two CAR-T products, idecabtagene vicleucel (ide-cel; Abecma) and ciltacabtagene autoleucel (cilta-cel, Carvykti), have been FDA- and EMA-approved for the treatment of relapsed/refractory MM (RRMM); both target B-cell maturation antigen (BCMA), a surface glycoprotein highly expressed on MM cells. Despite deep and durable responses following CAR-T therapy, most patients will need subsequent treatment, and the optimal next-line therapy is presently unclear. Commentary on: Liu et al. Outcomes in patients with multiple myeloma receiving salvage treatment after BCMA-specific CAR-T therapy: A retrospective analysis of LEGEND-2. Br J Haematol 2024;204:1780-1789.

Sequencing of therapy for patients with diffuse large B-cell lymphoma in the era of novel drugs.

Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive lymphoma, accounting for ~40% of all cases in adults. Whilst approximately two-thirds of DLBCL patients can be cured by first-line therapy, one-third of patients are primary refractory or relapse after an initial response (r/r DLBCL). Recent advances in the treatment of DLBCL have been achieved by a plethora of novel drugs, such as monoclonal antibodies, antibody-drug conjugates (ADC), bi-specific T-cell engagers (BITEs), and CD-19 directed chimeric antigen receptor (CAR)-T-cell therapies. The increasing number of therapeutic options significantly improved the outcome of patients; however, the therapeutic algorithm has become increasingly complex. In this review, we provide an overview of novel therapies for DLBCL patients and potential treatment sequencing from first to second, third, and later lines.

Breaking the shield of solid tumors: a combined approach for enhanced efficacy of CAR-T cells.

The use of chimeric antigen receptor (CAR)-T cells has enhanced the range of available therapeutic modalities in the context of cancer treatment. CAR-T cells have demonstrated considerable efficacy in the targeted eradication of blood cancer cells, thereby stimulating substantial interest in the advancement of such therapeutic approaches. However, the efficacy of CAR-T cells against solid tumor cells has been limited due to the presence of various obstacles. Solid tumors exhibit antigenic diversity and an immunosuppressive microenvironment, which presents a challenge for immune cells attempting to penetrate the tumor. CAR-T cells also demonstrate decreased proliferative activity and cytotoxicity. Furthermore, concerns exist regarding tumor antigen loss and therapy-associated toxicity. Currently, scientists are working to enhance the structure of the CAR and improve the survival and efficiency of CAR-T cells in recognizing tumor antigens in solid tumors. Chemotherapy drugs are frequently employed in the treatment of malignant neoplasms and can also be used prior to cell therapy to enhance CAR-T cell engraftment. Recent studies have demonstrated that chemotherapy drugs can mitigate the suppressive impact of TME, eliminate the physical barrier by destroying the tumor stroma, and facilitate greater penetration of immune cells and CAR-T cells into the tumor. This, in turn, increases their survival, persistence, and cytotoxicity, as well as affects the metabolism of immune cells inside the tumor. However, the effectiveness of the combined approach against solid tumors depends on several factors, including the type of tumor, dosage, population of CAR-T cells, and individual characteristics of the body. This review examines the principal obstacles to the utilization of CAR-T cells against solid tumors, proposes solutions to these issues, and assesses the potential advantages of a combined approach to radiation exposure, which has the potential to enhance the sensitivity of the tumor to other agents.

Highlight of 2023: Virtues and vices of CD4 CAR T cells.

This article for the Highlights of 2023 Series explores recent work that suggests that targeting CD4 CAR T cells may be critical for both of these challenges.

CAR T Cell Membrane Camouflaged Nanocatalyst Augments CAR T Cell Therapy Efficacy Against Solid Tumor.

The immunosuppressive tumor microenvironment (TME) reduces the chimeric antigen receptor (CAR) T-cell therapy against solid tumors. Here, a CAR T cell membrane-camouflaged nanocatalyst (ACSP@TCM) is prepared to augment CAR T cell therapy efficacy against solid tumors. ACSP@TCM is prepared by encapsulating core/shell Au/Cu2- xSe and 3-bromopyruvate with a CAR T cell membrane. It is demonstrated that the CAR T cell membrane camouflaging has much better-targeting effect than the homologous tumors cell membrane camouflaging. ACSP@TCM has an appealing synergistic chemodynamic/photothermal therapy (CDT/PTT) effect that can induce the immunogenic cell death (ICD) of NALM 6 cells. Moreover, 3-bromopyruvate can inhibit the efflux of lactic acid by inhibiting the glycolysis process, regulating the acidity of TME, and providing a more favorable environment for the survival of CAR T cells. In addition, the photoacoustic (PA) imaging and computed tomography (CT) imaging performance can guide the ACSP@TCM-mediated tumor therapy. The results demonstrated that the ACSP@TCM significantly enhanced the CAR T cell therapy efficacy against NALM 6 solid tumor mass, and completely eliminated tumors. This work provides an effective tumor strategy for CAR T cell therapy in solid tumors.

Disrupting B and T-cell collaboration in autoimmune disease: T-cell engagers versus CAR T-cell therapy?

B and T cells collaborate to drive autoimmune disease (AID). Historically, B- and T-cell (B-T cell) co-interaction was targeted through different pathways such as alemtuzumab, abatacept, and dapirolizumab with variable impact on B-cell depletion (BCD), whereas the majority of patients with AID including rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and organ transplantation benefit from targeted BCD with anti-CD20 monoclonal antibodies such as rituximab, ocrelizumab, or ofatumumab. Refractory AID is a significant problem for patients with incomplete BCD with a greater frequency of IgD-CD27+ switched memory B cells, CD19+CD20- B cells, and plasma cells that are not directly targeted by anti-CD20 antibodies, whereas most lymphoid tissue plasma cells express CD19. Furthermore, B-T-cell collaboration is predominant in lymphoid tissues and at sites of inflammation such as the joint and kidney, where BCD may be inefficient, due to limited access to key effector cells. In the treatment of cancer, chimeric antigen receptor (CAR) T-cell therapy and T-cell engagers (TCE) that recruit T cells to induce B-cell cytotoxicity have delivered promising results for anti-CD19 CAR T-cell therapies, the CD19 TCE blinatumomab and CD20 TCE such as mosunetuzumab, glofitamab, or epcoritamab. Limited evidence suggests that anti-CD19 CAR T-cell therapy may be effective in managing refractory AID whereas we await evaluation of TCE for use in non-oncological indications. Therefore, here, we discuss the potential mechanistic advantages of novel therapies that rely on T cells as effector cells to disrupt B-T-cell collaboration toward overcoming rituximab-resistant AID.

Unraveling resistance mechanisms in anti-CD19 chimeric antigen receptor-T therapy for B-ALL: a novel in vitro model and insights into target antigen dynamics.

BACKGROUND: Cellular immunotherapy, represented by the chimeric antigen receptor T cell (CAR-T), has exhibited high response rates, durable remission, and safety in vitro and in clinical trials. Unfortunately, anti-CD19 CAR-T (CART-19) treatment alone is prone to relapse and has a particularly poor prognosis in relapsed/refractory (r/r) B-ALL patients. To date, addressing or reducing relapse remains one of the research priorities to achieve broad clinical application. METHODS: We manufactured second generation CART-19 cells and validated their efficacy and safety in vitro and in vivo. Through co-culture of Nalm-6 cells with short-term cultured CART-19 cells, CD19-negative Nalm-6 cells were detected by flow cytometry, and further investigation of the relapsed cells and their resistance mechanisms was evaluated in vitro. RESULTS: In this study, we demonstrated that CART-19 cells had enhanced and specific antileukemic activities, and the survival of B-ALL mouse models after CART-19 treatment was significantly prolonged. We then shortened the culture time and applied the serum-free culture to expand CAR-T cells, followed by co-culturing CART-19 cells with Nalm-6 cells. Surprisingly, we observed the proliferation of CD19-negative Nalm-6 cells around 28 days. Identification of potential resistance mechanisms showed that the relapsed cells express truncated CD19 proteins with decreased levels and, more importantly, CAR expression was detected on the relapsed cell surface, which may ultimately keep them antigen-negative. Furthermore, it was validated that CART-22 and tandem CART-22/19 cells could effectively kill the relapsed cells, but neither could completely eradicate them. CONCLUSIONS: We successfully generated CART-19 cells and obtained a CD19-negative refractory relapsed B-ALL cell line, providing new insights into the underlying mechanisms of resistance and a new in vitro model for the treatment of r/r B-ALL patients with low antigen density.

Development of nanobodies targeting hepatocellular carcinoma and application of nanobody-based CAR-T technology.

BACKGROUND: Chimeric antigen receptor T (CAR-T) cell therapy, as an emerging anti-tumor treatment, has garnered extensive attention in the study of targeted therapy of multiple tumor-associated antigens in hepatocellular carcinoma (HCC). However, the suppressive microenvironment and individual heterogeneity results in downregulation of these antigens in certain patients' cancer cells. Therefore, optimizing CAR-T cell therapy for HCC is imperative. METHODS: In this study, we administered FGFR4-ferritin (FGFR4-HPF) nanoparticles to the alpaca and constructed a phage library of nanobodies (Nbs) derived from alpaca, following which we screened for Nbs targeting FGFR4. Then, we conducted the functional validation of Nbs. Furthermore, we developed Nb-derived CAR-T cells and evaluated their anti-tumor ability against HCC through in vitro and in vivo validation. RESULTS: Our findings demonstrated that we successfully obtained high specificity and high affinity Nbs targeting FGFR4 after screening. And the specificity of Nbs targeting FGFR4 was markedly superior to their binding to other members of the FGFR family proteins. Furthermore, the Nb-derived CAR-T cells, targeting FGFR4, exhibited significantly enhanced anti-tumor efficacy in both experiments when in vitro and in vivo. CONCLUSIONS: In summary, the results of this study suggest that the CAR-T cells derived from high specificity and high affinity Nbs, targeting FGFR4, exhibited significantly enhanced anti-tumor efficacy in vitro and in vivo. This is an exploration of FGFR4 in the field of Nb-derived CAR-T cell therapy for HCC, holding promise for enhancing safety and effectiveness in the clinical treatment of HCC in the future.