scholarly journals The Third Generation Anti-HER2 Chimeric Antigen Receptor Mouse T Cells Alone or Together With Anti-PD1 Antibody Inhibits the Growth of Mouse Breast Tumor Cells Expressing HER2 in vitro and in Immune Competent Mice

2020 ◽  
Vol 10 ◽  
Author(s):  
Panyuan Li ◽  
Lingcong Yang ◽  
Tong Li ◽  
Shufang Bin ◽  
Bohao Sun ◽  
...  
2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 150-150
Author(s):  
Sergei Kusmartsev ◽  
Johaness Vieweg ◽  
Victor Prima

150 Background: NKG2D is a lectin-like type 2 transmembrane receptor that expressed by natural killer cells and some T cell subsets. Stimulation of NKG2D receptor with specific agonistic ligands produces activating signals through signaling adaptor protein DAP10 leading to the enhanced cytokine production, proliferation, and cytotoxicity against tumor cells. There is strong evidence that NKG2D ligands are expressed in many human tumors, including melanoma, leukemia, myeloma, glioma, and carcinomas of the prostate, breast, lung, and colon. Recent studies also demonstrated that T cells bearing chimeric antigen receptor (CAR) NKG2D linked to CD3ζ (zeta) chain produce marked in vitro and in vivo anti-tumor effects. The aim of current study was to determine whether human T cells bearing chimeric antigen receptor (CAR) NKGD2 linked to CD3ε (epsilon) chain could be activated by the NKG2D-specific stimulation and able to kill human cancer cells. Given the important role of CD3ε in activation and survival of T cells, we hypothesized that NKG2D-CDε-bearing T cells could exert strong in vitro and in vivo anti-tumor effects. Methods: NKG2D CAR was produced by linking human NKG2D to DAP10 and the cytoplasmic portion of the CD3ε chain. Original full-length human cDNA clones were obtained from NIH Mammalian Gene Collection (MGC). Functional domain analysis and oligonucleotide design in the in-Fusion system of DNA cloning (Clontech) was used to generate the retroviral expression constructs. Results: Human PBMC-derived T cells were retrovirally transduced with newly generated NKG2D-CD3ε CAR DNA construct. These NKG2D CAR-expressing human T cells responded to NKG2D-specific activation by producing IFN-γ and exhibited significant cellular cytotoxicity against human tumor cells in vitro. In vivo studies demonstrated that NKG2D-CD3ε-bearing cells are capable of inhibiting growth of DU-145 human prostate cancer in the immunodeficient mice. Conclusions: Collectively, our data indicate the feasibility of developing chimeric antigen receptor NKG2D-CD3ε for T cells and suggest that adoptive transfer of T cells bearing NKG2D-CD3ε CAR could be potentially effective for immunotherapy of cancer patients.


2020 ◽  
Author(s):  
Liqing Kang ◽  
Jian Zhang ◽  
Minghao Li ◽  
Nan Xu ◽  
Wei Qi ◽  
...  

Abstract Background: Treatment with chimeric antigen receptor (CAR)-engineered T cells directed against the B-cell maturation antigen (BCMA) promoted transient recovery from multiple myeloma (MM). However, the absence of this antigen on immature plasma cells may limit the efficacy of this modality and facilitate relapse. The purpose of this study is to characterize a novel CAR that includes both a single-chain variable fragment (scFv)-BCMA and an scFv-CD19 in tandem orientation (tan-CAR) in an attempt to target both BCMA and CD19 expression on MM cells. Method: The scFv sequences from the anti-CD19 antibody FMC63 and the anti-BCMA antibody C11D5.3 were ligated in tandem with transmembrane and T-cell signaling domains to generate the tan-CAR construct. Specificity and efficacy of activated tan-CAR T cells were analyzed using in vitro proliferation, cytokine release, and cytolysis assays. We also evaluated the in vivo efficacy with a xenograft mouse model that included target tumor cells that expressed CD19 or BCMA and compared the results to those obtained with conventional CAR T cells. Results: The in vitro studies revealed specific activation of tan-CAR T cells by K562 cells that overexpressed CD19 and/or BCMA. Cell proliferation, cytokine release, and cytolytic activity were all comparable to the responses of single scFv CAR T cells. Importantly, in vivo studies of tan-CAR T cells revealed specific inhibition of tumor growth in the mouse xenograft model that included cells expressing both CD19 and BCMA. Systemic administration of tan-CAR T cells resulted in complete tumor remission, in contrast to the reduced efficacies of BCMA-CAR T and CD19-CAR T alone in this setting. Conclusion: We report the successful design and execution of novel tan-CAR T cells that promote significant anti-tumor efficacy against both CD19 and BCMA antigen-positive tumor cells in vitro and in vivo . The data from this study reveal a novel strategy that may help to reduce the rate of relapse in the treatment with single scFv-CAR T cells.


2021 ◽  
Vol 11 ◽  
Author(s):  
Xiaorui Li ◽  
Yaru Feng ◽  
Fengqin Shang ◽  
Zhuoying Yu ◽  
Tieshan Wang ◽  
...  

Multiple myeloma (MM) is a tumor type characterized by the unregulated proliferation of clonal plasma cells in the bone marrow. Immunotherapy based on chimeric antigen receptor T cell (CAR-T) therapy has achieved exciting success in the treatment of hematological malignant tumors. CD38 is highly and evenly expressed in MM and is an attractive target for MM treatment. Here, we successfully constructed two novel second-generation CAR-T cells targeting CD38 by retroviral vector transduction. CD38 CAR-T cells could be activated effectively after stimulation with CD38-positive tumor cells and secrete cytokines such as IFN-γ and TNF-α to promote tumor cell apoptosis in in vitro experiments. Real-time fluorescence monitoring experiments, luciferase detection experiments and flow cytometry experiments revealed the efficient and specific killing abilities of CD38 CAR-T cells against CD38-positive tumor cells. The proliferation ability of CD38 CAR-T cells in vitro was higher than that of untransduced T cells. Further antitumor experiments in vivo showed that CD38 CAR-T cells could be quickly activated to secrete IFN-γ and eliminate tumors. Thus, novel CD38-targeted second-generation CAR-T cells have efficient and specific antitumor activity and may become a novel therapy for the clinical treatment of MM.


2020 ◽  
Author(s):  
Liqing Kang ◽  
Jian Zhang ◽  
Minghao Li ◽  
Nan Xu ◽  
Wei Qi ◽  
...  

Abstract Background: Chimeric antigen receptor (CAR) engineered T cells directed B cell maturation antigen (BCMA) showed transient recovery to multiple myeloma (MM). However, the expression of CD19 on immature plasma cell may escape the recognition by BCMA-CAR T, which restrict the efficacy and facilitate to relapse. The purpose of this study is to characterize a novel CAR structure with a tandem orientation of scFv-BCMA and scFv-CD19, tandem CAR (tan-CAR), to provide an effective solution for killing both BCMA and/or CD19 expression MM cells.Method: Single-chain variable fragment (scFv) sequences from the anti-CD19 antibody FMC63 and the anti-BCMA antibody C11D5.3 were ligated in tandem with transmembrane and T cell signaling domains to achieve tan-CAR construct. The therapeutic specificity and efficiency were analyzed for tan-CAR T cells activation, proliferation, cytokine release and cytolytic toxicity in vitro. Also, in vivo efficacy evaluation conducted in xenograft mouse models with the combination of two corresponding target tumor cells, in comparison with conventional CAR.Results: The in vitro studies demonstrated specific activation of tan-CAR T cells to the K562 tumor cell overexpressing CD19, BCMA, or both. Besides, it also elicits the comparable immunoreactivities, in terms of proliferation, cytokine release and cytolytic activity compared to single scFv modified CAR T cells. Importantly, the in vivo studies of tan-CAR-transduced T cells results specific inhibition of tumor growth in xenograft model that express combined tumor antigen i.e. CD19 and BCMA. Moreover, systemic administration of tan-CAR resulted in complete tumor remission, whilst neither BCMA-CAR T nor CD19-CAR-T could. Conclusion: A novel tan-CAR T was successfully designed and showed the significant antitumor efficacy for combined antigen-positive tumor cells in vitro and in vivo. However, the single CAR T cells with targeting one antigen didn’t achieve similar potency. The data from this study suggest a novel strategy to help reduce relapse due to existing CD19-expressing multiple myeloma cells or downregulation of the BCMA antigen after CAR-based treatment of multiple myeloma.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii112-ii112
Author(s):  
Radhika Thokala ◽  
Zev Binder ◽  
Yibo Yin ◽  
Michael Milone ◽  
Donald M O’Rourke

Abstract Tumor heterogeneity is one of the key reasons for therapeutic failure in Glioblastoma (GBM). Our chimeric antigen receptor (CAR) T cell clinical trial (NCT02209376) against Epidermal growth factor receptor (EGFR) variant III (EGFRvIII) demonstrated successful trafficking of T cells across the blood brain barrier into GBM active tumor sites. However, CART cell infiltration was associated with a selective loss of EGFRvIII+ tumor cells and upregulation of immunosuppressive molecules. Post-CAR T treated tumor specimens showed continued presence of EGFR amplification and oncogenic EGFR extracellular domain (ECD) missense mutations. To study this further We generated two structurally different CARs by fusing the scFv of mAb806 to 4-1BB and Killer immunoglobulin like receptor (KIR) co-stimulatory domains. Both 4-1BB and KIR based EGFR806 CAR T cells specifically lysed tumor cells and secreted cytokines when co-cultured with U87-MG (expressing low levels of EGFR) and U87-MG EGFR (U87-MG transduced with EGFR wild type for amplified background) cell lines and engineered to ectopically express targeted EGFR-ECD missense mutations and EGFRvIII. Unlike EGFR-specific cetuximab based CAR, EGFR-806CART cells did not kill EGFR wild type expressing fetal brain primary astrocytes and keratinocytes in vitro. We further evaluated the in vivo efficacy of 806-CARs and EGFRvIII CART currently in clinic in NSG mice. While EGFRvIII CART cells cleared EGFRvIII+ tumors alone 806 CART cells controlled EGFRvIII, amplified EGFR and EGFRR108K-mutant bearing tumors. KIR-CAR treated tumors are GVHD free and enhanced survival compared to 4-1BB based CARs. The broad specificity of EGFR806 CART cells to amplified EGFR and its mutant variants gives us the potential to clear various forms of EGFR. The enhanced anti-tumor efficacy by KIR based CAR in vivo setting provides us with additional therapeutic options.


PLoS ONE ◽  
2016 ◽  
Vol 11 (12) ◽  
pp. e0166891 ◽  
Author(s):  
Kentaro Minagawa ◽  
Muhammad O. Jamil ◽  
Mustafa AL-Obaidi ◽  
Larisa Pereboeva ◽  
Donna Salzman ◽  
...  

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248973
Author(s):  
Nami Iwamoto ◽  
Bhavik Patel ◽  
Kaimei Song ◽  
Rosemarie Mason ◽  
Sara Bolivar-Wagers ◽  
...  

Achieving a functional cure is an important goal in the development of HIV therapy. Eliciting HIV-specific cellular immune responses has not been sufficient to achieve durable removal of HIV-infected cells due to the restriction on effective immune responses by mutation and establishment of latent reservoirs. Chimeric antigen receptor (CAR) T cells are an avenue to potentially develop more potent redirected cellular responses against infected T cells. We developed and tested a range of HIV- and SIV-specific chimeric antigen receptor (CAR) T cell reagents based on Env-binding proteins. In general, SHIV/SIV CAR T cells showed potent viral suppression in vitro, and adding additional CAR molecules in the same transduction resulted in more potent viral suppression than single CAR transduction. Importantly, the primary determinant of virus suppression potency by CAR was the accessibility to the Env epitope, and not the neutralization potency of the binding moiety. However, upon transduction of autologous T cells followed by infusion in vivo, none of these CAR T cells impacted either acquisition as a test of prevention, or viremia as a test of treatment. Our study illustrates limitations of the CAR T cells as possible antiviral therapeutics.


2021 ◽  
Author(s):  
Yannick D. Muller ◽  
Leonardo M.R. Ferreira ◽  
Emilie Ronin ◽  
Patrick Ho ◽  
Vinh Nguyen ◽  
...  

Infusion of regulatory T cells (Tregs) engineered with a chimeric antigen receptor (CAR) targeting donor-derived human leukocyte antigen (HLA) is a promising strategy to promote transplant tolerance. Here, we describe an anti-HLA-A2 CAR (A2-CAR) generated by grafting the complementarity-determining regions (CDRs) of a human monoclonal anti-HLA-A2 antibody into the framework regions of the Herceptin 4D5 single-chain variable fragment and fusing it with a CD28-zeta signaling domain. The CDR-grafted A2-CAR maintained the specificity of the original antibody. We then generated HLA-A2 mono-specific human CAR Tregs either by deleting the endogenous T-cell receptor (TCR) via CRISPR/Cas9 and introducing the A2-CAR using lentiviral transduction or by directly integrating the CAR construct into the TCR alpha constant locus using homology-directed repair. These A2-CAR+TCRdeficient human Tregs maintained both Treg phenotype and function in vitro. Moreover, they selectively accumulated in HLA-A2-expressing islets transplanted from either HLA-A2 transgenic mice or deceased human donors. A2-CAR+TCRdeficient Tregs did not impair the function of these HLA-A2+ islets, whereas similarly engineered A2-CAR+TCRdeficientCD4+ conventional T cells rejected the islets in less than 2 weeks. A2-CAR+TCRdeficient Tregs delayed graft-versus-host disease only in the presence of HLA-A2, expressed either by co-transferred peripheral blood mononuclear cells or by the recipient mice. Altogether, we demonstrate that genome-engineered mono-antigen-specific A2-CAR Tregs localize to HLA-A2-expressing grafts and exhibit antigen-dependent in vivo suppression, independent of TCR expression. These approaches may be applied towards developing precision Treg cell therapies for transplant tolerance.


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