搜索结果: 'gmp t cell activator'

IntroductionCytokine release syndrome (CRS) is one of the leading causes of mortality in patients with COVID-19 caused by the SARS-CoV-2 coronavirus. However,the mechanism of CRS induced by SARS-CoV-2 is vague.MethodsUsing spike protein combined with IL-2,IFN-γ,and TNF-α to stimulate human peripheral blood mononuclear cells (PBMCs) to secrete CRS-related cytokines,the content of cytokines in the supernatant was detected,and the effects of NK,T,and monocytes were analyzed.ResultsThis study shows that dendritic cells loaded with spike protein of SARS-CoV-2 stimulate T cells to release much more interleukin-2 (IL-2,) which subsequently cooperates with spike protein to facilitate PBMCs to release IL-1β,IL-6,and IL-8. These effects are achieved via IL-2 stimulation of NK cells to release tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ),as well as T cells to release IFN-γ Mechanistically,IFN-γ and TNF-α enhance the transcription of CD40,and the interaction of CD40 and its ligand stabilizes the membrane expression of toll-like receptor 4 (TLR4) that serves as a receptor of spike protein on the surface of monocytes. As a result,there is a constant interaction between spike protein and TLR4,leading to continuous activation of nuclear factor-κ-gene binding (NF-κB). Furthermore,TNF-α also activates NF-κB signaling in monocytes,which further cooperates with IFN-γ and spike protein to modulate NF-κB–dependent transcription of CRS-related inflammatory cytokines.DiscussionTargeting TNF-α/IFN-γ in combination with TLR4 may represent a promising therapeutic approach for alleviating CRS in individuals with COVID-19. View Publication

The intracellular expression of the programmed death receptor 1 (PD1) identifies a subset of naive T(reg) cells with enhanced suppressive ability; antigen stimulation results in the surface expression of PD1. Because the role of T(reg) impairments in multiple sclerosis (MS) is still contradictory,we analyzed naive PD1- and PD1+ T(reg) cells in peripheral blood and cerebrospinal fluid (CSF) of relapsing-remitting multiple sclerosis (RR-MS) patients and of healthy control subjects. Results showed that 1) CSF PD1- T(reg) cells were significantly augmented in MS patients; 2) PD1- T(reg) cells were significantly increased in the peripheral blood of patients with stable disease (SMS) compared to those with acute (AMS) disease,and in patients responding to glatiramer acetate (COPA) compared to AMS- and COPA-unresponsive patients; and 3) PD1+ T(reg) cells were similar in CSF and peripheral blood of all groups analyzed. PD1- T(reg) cells were not increased in the peripheral blood of interferon-beta (IFNbeta) -responsive patients,but the suppressive ability of T(reg) cells was significantly higher in SMS and in COPA- or IFNbeta-responsive compared to AMS- and COPA-unresponsive individuals. The data herein suggest that PD1- T(reg) cells play a pivotal role in MS and offer a biological explanation for disease relapse and for the mechanism associated with response to COPA and IFNbeta. View Publication

The activating receptor NKG2D,expressed by natural killer (NK) cells and CD8(+) T cells,has a role in the specific killing of transformed cells. We examined NKG2D expression in patients with glioblastoma multiforme and found that NKG2D was downregulated on NK cells and CD8(+) T cells. Expression of NKG2D on lymphocytes significantly increased following tumor resection and correlated with an increased ability to kill NKG2D ligand-positive tumor targets. Despite the presence of soluble NKG2D ligands in the sera of glioblastoma patients,NKG2D downregulation was primarily caused by tumor-derived tumor growth factor-beta,suggesting that blocking of this cytokine may have therapeutic benefit. View Publication

DNA repair mechanisms in human primary cells,including error-free repair,and,recurrent nuclease cleavage events,remain largely uncharacterised. We elucidate gene-editing related repair processes using Cleavage and Lesion Evaluation via Absolute Real-time dPCR (CLEAR-time dPCR),an ensemble of multiplexed dPCR assays that quantifies genome integrity at targeted sites. Utilising CLEAR-time dPCR we track active DSBs,small indels,large deletions,and other aberrations in absolute terms in clinically relevant edited cells,including HSPCs,iPSCs,and T-cells. By quantifying up to 90% of loci with unresolved DSBs,CLEAR-time dPCR reveals biases inherent to conventional mutation screening assays. Furthermore,we accurately quantify DNA repair precision,revealing prevalent scarless repair after blunt and staggered end DSBs and recurrent nucleases cleavage. This work provides one of the most precise analyses of DNA repair and mutation dynamics,paving the way for mechanistic studies to advance gene therapy,designer editors,and small molecule discovery. Quantifying genomic aberrations resulting from designer nucleases activity is essential for gene therapy clinical translation. Here,the authors present a modular digital PCR technique that profiles DNA repair precision and cut-repair cycles at the edited loci,exposing current evaluation biases. View Publication

Allogeneic CAR T–cell therapies are being developed for hematologic malignancies. The authors implement a Cas12a chRDNA platform to generate allogeneic immune-cloaked BCMA-specific CAR T cells with resistance to host response–mediated rejection for evaluation in multiple myeloma. AbstractAllogeneic chimeric antigen receptor (CAR) T cell therapies hold the potential to overcome many of the challenges associated with patient-derived (autologous) CAR T cells. Key considerations in the development of allogeneic CAR T cell therapies include prevention of graft-vs-host disease (GvHD) and suppression of allograft rejection. Here,we describe preclinical data supporting the ongoing first-in-human clinical study,the CaMMouflage trial (NCT05722418),evaluating CB-011 in patients with relapsed/refractory multiple myeloma. CB-011 is a hypoimmunogenic,allogeneic anti–B-cell maturation antigen (BCMA) CAR T cell therapy candidate. CB-011 cells feature 4 genomic alterations and were engineered from healthy donor–derived T cells using a Cas12a CRISPR hybrid RNA–DNA (chRDNA) genome-editing technology platform. To address allograft rejection,CAR T cells were engineered to prevent endogenous HLA class I complex expression and overexpress a single-chain polyprotein complex composed of beta-2 microglobulin (B2M) tethered to HLA-E. In addition,T-cell receptor (TCR) expression was disrupted at the TCR alpha constant locus in combination with the site-specific insertion of a humanized BCMA-specific CAR. CB-011 cells exhibited robust plasmablast cytotoxicity in vitro in a mixed lymphocyte reaction in cell cocultures derived from patients with multiple myeloma. In addition,CB-011 cells demonstrated suppressed recognition by and cytotoxicity from HLA-mismatched T cells. CB-011 cells were protected from natural killer cell–mediated cytotoxicity in vitro and in vivo due to endogenous promoter-driven expression of B2M–HLA-E. Potent antitumor efficacy,when combined with an immune-cloaking armoring strategy to dampen allograft rejection,offers optimized therapeutic potential in multiple myeloma. See related Spotlight by Caimi and Melenhorst,p. 385 View Publication

Mycobacterium tuberculosis ( Mtb ),the causative agent of tuberculosis (TB),is the most common coinfection among people living with HIV-1. This coinfection is associated with accelerated HIV-1 disease progression and reduced survival. However,the impact of the HIV-1/TB coinfection on HIV-1 replication and latency in CD4 + T cells remains poorly studied. Using the acellular fraction of tuberculous pleural effusion (TB-PE),we investigated whether viral replication and HIV-1 latency in CD4 + T cells are affected by a TB-associated microenvironment. Our results revealed that TB-PE impaired T cell receptor-dependent cell activation and decreased HIV-1 replication in CD4 + T cells. Moreover,this immunosuppressive TB microenvironment promoted viral latency and inhibited HIV-1 reactivation. This study indicates that the TB-induced immune response may contribute to the persistence of the viral reservoir by silencing HIV-1 expression,allowing the virus to persist undetected by the immune system,and increasing the size of the latent HIV-1 reservoir. Subject areas: Immunology,Virology View Publication

Imaging strategies to monitor chimeric antigen receptor (CAR) T-cell biodistribution and proliferation harbor the potential to facilitate clinical translation for the treatment of both liquid and solid tumors. In addition,the potential adverse effects of CAR T cells highlight the need for mechanisms to modulate CAR T-cell activity. The herpes simplex virus type 1 thymidine kinase (HSV1-tk) gene has previously been translated as a PET reporter gene for imaging of T-cell trafficking in patients with brain tumor. The HSV1-TK enzyme can act as a suicide gene of transduced cells through treatment with the prodrug ganciclovir. Here we report the molecular engineering,imaging,and ganciclovir-mediated destruction of B7H3 CAR T cells incorporating a mutated version of the HSV1-tk gene (sr39tk) with improved enzymatic activity for ganciclovir. The sr39tk gene did not affect B7H3 CAR T-cell functionality and in vitro and in vivo studies in osteosarcoma models showed no significant effect on B7H3 CAR T-cell antitumor activity. PET/CT imaging with 9-(4-[18F]-fluoro-3-[hydroxymethyl]butyl)guanine ([18F]FHBG) of B7H3-sr39tk CAR T cells in an orthotopic model of osteosarcoma revealed tumor homing and systemic immune expansion. Bioluminescence and PET imaging of B7H3-sr39tk CAR T cells confirmed complete tumor ablation with intraperitoneal ganciclovir administration. This imaging and suicide ablation system can provide insight into CAR T-cell migration and proliferation during clinical trials while serving as a suicide switch to limit potential toxicities. SIGNIFICANCE: This study showcases the only genetically engineered system capable of serving the dual role both as an effective PET imaging reporter and as a suicide switch for CAR T cells. View Publication

The rising incidence of autoimmune diseases such as multiple sclerosis (MS) in developed countries might be due to a more hygienic environment,particularly during early life. To investigate this concept,we developed a model of neonatal exposure to a common pathogen-associated molecular pattern,LPS,and determined its impact on experimental autoimmune encephalomyelitis (EAE). Mice exposed to LPS at 2 wk of age showed a delayed onset and diminished severity of myelin oligodendrocyte glycoprotein (MOG)-induced EAE,induced at 12 wk,compared with vehicle-exposed animals. Spinal cord transcript levels of CD3epsilon and F4/80 were lower in LPS- compared with PBS-exposed EAE animals with increased IL-10 levels in the LPS-exposed group. Splenic CD11c(+) cells from LPS-exposed animals exhibited reduced MHC class II and CD83 expression but increased levels of CD80 and CD86 both before and during EAE. MOG-treated APC from LPS-exposed animals stimulated less T lymphocyte proliferation but increased expansion of CD4(+)FoxP3(+) T cells compared with APC from PBS-exposed animals. Neuropathological studies disclosed reduced myelin and axonal loss in spinal cords from LPS-exposed compared with PBS-exposed animals with EAE,and this neuroprotective effect was associated with an increased number of CD3(+)FoxP3(+) immunoreactive cells. Analyses of human brain tissue revealed that FoxP3 expression was detected in lymphocytes,albeit reduced in MS compared with non-MS patients' brains. These findings support the concept of early-life microbial exposure influencing the generation of neuroprotective regulatory T cells and may provide insights into new immunotherapeutic strategies for MS. View Publication

Infection with human immunodeficiency virus (HIV)-1 induces a progressive deterioration of the immune system that ultimately leads to acquired immune deficiency syndrome (AIDS). Murine models indicate that the common γ-chain (γ(c))-sharing cytokine interleukin (IL)-21 and its receptor (IL-21R) play a crucial role in maintaining polyfunctional T cell responses during chronic viral infections. Therefore,we analyzed the ability of this cytokine to modulate the properties of human CD8 T cells in comparison with other γ(c)-sharing cytokines (IL-2,IL-7,and IL-15). CD8 T cells from healthy volunteers were stimulated in vitro via T cell receptor signals to mimic the heightened status of immune activation of HIV-infected patients. The administration of IL-21 upregulated cytotoxic effector function and the expression of the costimulatory molecule CD28. Notably,this outcome was not accompanied by increased cellular proliferation or activation. Moreover,IL-21 promoted antiviral activity while not inducing HIV-1 replication in vitro. Thus,IL-21 may be a favorable molecule for immunotherapy and a suitable vaccine adjuvant in HIV-infected individuals. View Publication

Transitioning CD19-directed chimeric antigen receptor (CAR) T cells from early-phase trials in relapsed patients to a viable therapeutic approach with predictable efficacy and low toxicity for broad application among patients with high unmet need is currently complicated by product heterogeneity resulting from transduction of undefined T-cell mixtures,variability of transgene expression,and terminal differentiation of cells at the end of culture. A phase 1 trial of 45 children and young adults with relapsed or refractory B-lineage acute lymphoblastic leukemia was conducted using a CD19 CAR product of defined CD4/CD8 composition,uniform CAR expression,and limited effector differentiation. Products meeting all defined specifications occurred in 93{\%} of enrolled patients. The maximum tolerated dose was 106 CAR T cells per kg,and there were no deaths or instances of cerebral edema attributable to product toxicity. The overall intent-to-treat minimal residual disease-negative (MRD-) remission rate for this phase 1 study was 89{\%}. The MRD- remission rate was 93{\%} in patients who received a CAR T-cell product and 100{\%} in the subset of patients who received fludarabine and cyclophosphamide lymphodepletion. Twenty-three percent of patients developed reversible severe cytokine release syndrome and/or reversible severe neurotoxicity. These data demonstrate that manufacturing a defined-composition CD19 CAR T cell identifies an optimal cell dose with highly potent antitumor activity and a tolerable adverse effect profile in a cohort of patients with an otherwise poor prognosis. This trial was registered at www.clinicaltrials.gov as {\#}NCT02028455. View Publication

SummaryAlthough chimeric antigen receptor (CAR) T cells have demonstrated therapeutic activity in hematopoietic malignancies,tumor heterogeneity has impeded the efficacy of CAR T cells and their extension into successful solid tumor treatment. To address these challenges,induced pluripotent stem cell (iPSC)-derived T (iT) cells are engineered to uniformly express CAR and T cell receptor (TCR),enabling targeting of both surface and intracellular antigens,respectively,along with a high-affinity,non-cleavable variant of CD16a (hnCD16) to support antibody-dependent cellular cytotoxicity (ADCC) when combined with therapeutic antibodies. Co-expression of each antitumor strategy on engineered iT cells enables independent and antigen-specific targeting across a diverse set of liquid and solid tumors. In heterogeneous tumor models,coactivation of these modalities is required for measurable antitumor efficacy,with activation of all three modalities displaying maximal efficacy. These data highlight the therapeutic potential of an off-the-shelf engineered iPSC-derived trimodal T cell expressing CAR,TCR,and hnCD16 to combat difficult-to-treat heterogeneous tumors. Graphical abstract Highlights•CAR,TCR,and hnCD16 can be uniformly co-expressed and can function in iT cells•hnCD16 signals through CD3ζ and arms iT cells with targeting flexibility through ADCC•Concurring CAR,TCR,and hnCD16 activation demonstrates a cooperative effect•Multi-targeting with trimodal iT cells can control heterogeneous tumors in vivo Yang et al. show that (1) trimodal iPSC cells expressing CAR,TCR,and hnCD16 can commit to T cell lineage,(2) hnCD16 signals through CD3ζ in iT cells and arms iT cells with ADCC targeting flexibility,and (3) trimodal iT cells control antigen-heterogeneous tumors in vivo through multi-modal targeting. View Publication

Understanding the mechanisms of CD4 memory T cell (Tmem) differentiation in malaria is critical for vaccine development. However,the metabolic regulation of CD4 Tmem differentiation is not clear,particularly in persistent infections. In this study,we investigated the role of fatty acid synthesis (FAS) in Tmem development in Plasmodium chabaudi chronic mouse malaria infection. We show that T cell-specific deletion and early pharmaceutical inhibition of acetyl CoA carboxylase 1,the rate limiting step of FAS,inhibit generation of early memory precursor effector T cells (MPEC). To compare the role of FAS during early differentiation or survival of Tmem in chronic infection,a specific inhibitor of acetyl CoA carboxylase 1,5-(tetradecyloxy)-2-furoic acid,was administered at different times postinfection. Strikingly,the number of Tmem was only reduced when FAS was inhibited during T cell priming and not during the Tmem survival phase. FAS inhibition during priming increased effector T cell (Teff) proliferation and strongly decreased peak parasitemia,which is consistent with improved Teff function. Conversely,MPEC were decreased,in a T cell-intrinsic manner,upon early FAS inhibition in chronic,but not acute,infection. Early cure of infection also increased mitochondrial volume in Tmem compared with Teff,supporting previous reports in acute infection. We demonstrate that the MPEC-specific effect was due to the higher fatty acid content and synthesis in MPEC compared with terminally differentiated Teff. In conclusion,FAS in CD4 T cells regulates the early divergence of Tmem from Teff in chronic infection. View Publication