CAR T cells: Building on the CD19 paradigm

Spearheaded by the therapeutic use of chimeric antigen receptors (CARs) targeting CD19, synthetic immunology has entered the clinical arena. CARs are recombinant receptors for antigen that engage cell surface molecules through the variable region of an antibody and signal through arrayed T-cell activating and costimulatory domains. CARs allow redirection of T-cell cytotoxicity against any antigen of choice, independent of MHC expression. Patient T cells engineered to express CARs specific for CD19 have yielded remarkable outcomes in subjects with relapsed/refractory B- cell malignancies, setting off unprecedented interest in T-cell engineering and cell-based cancer immunotherapy. In this review, we present the challenges to extend the use of CAR T cells to solid tumors and other pathologies. We further highlight progress in CAR design, cell manufacturing, and genome editing, which in aggregate hold the promise of generating safer and more effective genetically instructed immunity. Novel engineered cell types, including innate T-cell types, natural killer (NK) cells, macrophages, and induced pluripotent stem cell-derived immune cells, are on the horizon, as are applications of CAR T cells to treat autoimmunity, severe infections, and senescence-associated pathologies.     

沉默Notch1基因促进人乳腺癌MCF-7细胞JNK1和p53磷酸化

 目的：探究沉默Notch1基因对人乳腺癌MCF-7细胞JNK1和p53磷酸化的影响。方法：选取人乳腺癌MCF-7细胞作为研究对象,构建shRNA-Notch1真核表达质粒用于转染MCF-7细胞使Notch1基因沉默。采用Western blotting方法检测MCF-7细胞Notch1、Hes-1、PUMA和NOXA蛋白的表达,JNK1和p53蛋白磷酸化水平以及caspase-3活化水平的改变。应用流式细胞术检测细胞凋亡和线粒体膜电位的变化。结果：人乳腺癌MCF-7细胞Notch1基因被沉默后,Notch1和Hes-1蛋白表达量明显减少(P<0.01),细胞凋亡率显著升高(P<0.01),JNK1和p53的磷酸化水平明显高于对照组(P<0.01),PUMA和NOXA表达量显著升高(P<0.05),cleaved caspase-3蛋白明显多于对照组(P<0.01),线粒体膜电位明显下降(P<0.05)。结论：沉默Notch1基因可能通过激活JNK1信号通路活化p53,促进PUMA和NOXA蛋白表达,进而通过线粒体途径导致人乳腺癌MCF-7细胞凋亡。     

Molecular regulatory network of PD-1/PD-L1 in non-small cell lung cancer

Lung cancer remains the most common cancer and the leading cause of cancer death worldwide. Despite effective chemotherapy and molecular-based therapies, the median and overall survival remains poor. Immune checkpoint inhibitors have changed the treatment landscape for patients with non-small cell lung cancer (NSCLC) by inhibiting negative T cell regulators, including programmed death 1 (PD-1, CD279) and programmed death ligand 1 (PD-L1, also known as B-H1, CD274) inhibitors. Nonetheless, most patients do not respond to these inhibitors. Recently, PD-L1 expression has been demonstrated to influence the anti-tumor efficacy of immune checkpoint inhibitors. However, the mechanisms of PD-L1 regulation are not clearly understood. This review thus aims to summarize the current knowledge and recent developments in the regulatory mechanisms of PD-L1 expression levels and attempts to clarify its latent function in anti-tumor activity, with the goal of guiding better designs for future NSCLC immunotherapies.     

TIGIT and PD-1 may serve as potential prognostic biomarkers for gastric cancer

Gastric Cancer (GC) is the fifth leading cause of cancer-related death in the world, and in urgent need of specific therapeutic targets to acquire prominent effectiveness. T-cell immunoglobulin and immunoreceptor tyrosine–based inhibitory motif (ITIM) domain (TIGIT) and programmed cell death protein 1 (PD-1) are identified to be abnormally overexpressed in various types of cancers including GC. This study aimed to investigate whether TIGIT and PD-1 could serve as potential prognostic biomarkers for GC. Firstly, TCGA GC dataset analysis and correlation analysis were utilized to inspect the relationship between expression of TIGIT, PD-1 and CD8 + T cells in GC and adjacent normal tissues. Then, flow cytometry was used to verify the data after collecting the peripheral blood, GC and adjacent normal tissues from 150 GC patients. Lastly, quantitative RT-PCR was performed to detect the expression of CD155, CD113, CD112 and TIGIT in six human GC cell lines and 631 GC patients in KM Plotter Database to conduct prognostic analysis. As results, we found that TIGIT and PD-1 were upregulated in GC tissues with high CD8 + T cells infiltration, while correlation analysis indicated they were in high-positive correlation. In addition, the flow cytometry analysis further showed that the high-expression of TIGIT in tumor microenvironment of GC could suppress the function of infiltrative CD8 + T cells, which leads to the escape of GC cells from immune killing. Furthermore, CD155 and CD112 were found abnormally upregulated in GC tissues and cell lines and the high expression of CD155, CD112 and TIGIT demonstrated poor prognosis results. In conclusion, these results provided potential therapeutic targets and prognostic biomarkers for treatment of GC in clinic.     

沉默JAG1基因对人乳腺癌MDA-MB-231细胞增殖和凋亡的影响

 目的:探究沉默Jagged 1 (JAG1)基因对人乳腺癌MDA-MB-231细胞增殖和凋亡的影响及其分子生物学机制。方法:
用已构建的pRS-JAG1重组质粒转染人乳腺癌MDA-MB-231细胞, 采用Western blotting方法检测重组质粒对JAG1蛋白表达的影响;MTT比色法测定沉默JAG1对细胞生长的抑制情况;流式细胞术检测细胞周期和细胞凋亡;蛋白印记分析细胞周期蛋白1(cyclin D1)、p21CIP1/WAF1、p27KIP1、p-Rb、Bcl-2、Bax、Bcl-xL和cleaved caspase-3蛋白水平的变化。结果:Western blotting结果证实重组质粒可在72h内有效抑制JAG1蛋白表达;人乳腺癌MDA-MB-231细胞JAG1被沉默后,细胞的生长速度明显减慢,细胞明显阻滞于G 0/G 1期,细胞凋亡率显著升高(P<0.05),cyclin D1、p-Rb、Bcl-2和Bcl-xL蛋白水平被下调(P<0.05),而p21CIP1/WAF1、p27KIP1、Bax和cleaved caspase-3的蛋白水平显著升高(P<0.05)。结论:沉默JAG1可有效抑制人乳腺癌MDA-MB-231细胞增殖,并诱导其凋亡。本研究为以JAG1为分子靶点的三阴乳腺癌治疗提供实验依据。     

Adoptive T‐cell therapy for cancer: The era of engineered T cells

Tumors originate from a number of genetic events that deregulate homeostatic mechanisms controlling normal cell behavior. The immune system, devoted to patrol the organism against pathogenic events, can identify transformed cells, and in several cases cause their elimination. It is however clear that several mechanisms encompassing both central and peripheral tolerance limit antitumor immunity, often resulting into progressive diseases. Adoptive T‐cell therapy with either allogeneic or autologous T cells can transfer therapeutic immunity. To date, genetic engineering of T cells appears to be a powerful tool for shaping tumor immunity. In this review, we discuss the most recent achievements in the areas of suicide gene therapy, and TCR‐modified T cells and chimeric antigen receptor gene‐modified T cells. We provide an overview of current strategies aimed at improving the safety and efficacy of these approaches, with an outlook on prospective developments.     

shRNA介导的hWAPL表达沉默对人宫颈癌CaSki细胞增殖与凋亡的影响

 目的： 为探讨人半翼(hWAPL)蛋白在细胞增殖与凋亡中的作用及其作为分子靶点用于肿瘤治疗的潜在价值,本研究用RNA干扰技术抑制hWAPL基因的表达,并观察了其对人宫颈癌细胞CaSki细胞增殖和细胞凋亡的影响。方法：实时荧光定量PCR和Western blotting 检测hWAPL shRNA的干扰效率;MTT检测细胞增殖;Annexin V-PE和 Hoechst 33258染色检测细胞凋亡;蛋白质印迹分析凋亡蛋白cleaved caspase-3和细胞周期抑制蛋白p21、p27的表达。裸鼠荷瘤模型体内研究hWAPL沉默对CaSki细胞增殖的影响。结果：实时荧光定量PCR和Western blotting检测结果表明,筛选到的hWAPL shRNA能有效抑制内源hWAPL的表达。MTT实验表明 shRNA介导的hWAPL表达沉默显著抑制CaSki细胞的增殖。Annexin V-PE分析结果表明, hWAPL 沉默增加了凋亡细胞数目。细胞核经Hoechst　33258染色出现浓染致密的固缩形态和颗粒状荧光; 蛋白质印迹结果显示cleaved caspase-3、 p21和p27表达增加;裸鼠成瘤实验表明,hWAPL 沉默的肿瘤体积减小,增殖细胞核抗原(PCNA)蛋白表达增加。结论：hWAPL沉默抑制CaSki细胞增殖,促进细胞凋亡,是一个潜在的肿瘤治疗新靶点。     

嵌合抗原受体修饰T细胞研究进展及肿瘤靶抗原的选择

嵌合抗原受体修饰T细胞(CAR-T)是目前恶性肿瘤免疫治疗的一种新方法。CAR-T细胞对肿瘤的杀伤不依赖主要组织相容性复合体(MHC),并可克服肿瘤局部免疫抑制微环境和突破宿主免疫耐受状态,因此,CAR-T细胞在治疗肿瘤方面具有独特的优势。CAR-T细胞的构建和选择合适的靶分子是CAR-T细胞免疫治疗的两个关键的问题,我们在文中将围绕这两个问题做一综述。     

肿瘤抗原特异性T细胞受体改造的T细胞研究现状及应用前景

近年来,肿瘤免疫治疗在临床取得了令人振奋的疗效,给肿瘤治疗带来了新的希望。T细胞受体改造的T细胞(T cell receptor engineered T cells,TCR-T)过继疗法是将肿瘤抗原特异性TCR基因导入患者T细胞中,在体外扩增后回输到患者体内进行靶向抗肿瘤治疗的技术。一些临床试验已经证实了该疗法具有一定的可行性和发展潜力。随着基因测序和基因编辑等技术的发展,TCR-T细胞疗法也在抗肿瘤治疗中取得了一些新的进展。本文将对TCR-T细胞免疫治疗的研究现状、进展、临床试验效果及存在的问题和发展前景进行综述。     

CAR-T细胞免疫疗法的现状及展望

肿瘤细胞免疫治疗被公认为是继手术、放疗和化疗之后的第四种肿瘤治疗方法,免疫疗法嵌合型抗原受体(chimeric antigen receptor,CAR)修饰的T细胞疗法(CAR-T),属于过继性细胞免疫治疗,不仅在肿瘤治疗中取得突破性进展,在感染性疾病和自身免疫性疾病等治疗中也有良好的应用前景.现就CAR-T细胞免疫疗法的发展历史、临床应用、目前存在的问题以及最新研究成果作一综述.     

PD-1敲除及GPC3修饰的嵌合抗原受体T细胞治疗肝癌的实验研究

目的 构建程序死亡受体1(PD-1)敲除及磷脂酰肌醇蛋白多糖-3(GPC3)修饰的嵌合抗原受体T细胞(GPC3-PD1gRNA-CART cells),研究其对肝癌细胞株HepG2的体外杀伤作用,以及其对肝癌动物模型的体内抗肿瘤作用.方法 制备GPC3-PD1gRNA-CART细胞,用流式细胞仪检测PD-1、GPC3 ...     

CAR T cells: driving the road from the laboratory to the clinic

Blockbuster antibody therapies have catapulted immune-based approaches to treat cancer into the consciousness of mainstay clinical research. On the back of this, other emerging immune-based therapies are providing great promise. T-cell therapy is one such area where recent trials using T cells genetically modified to express an antibody-based chimeric antigen receptor (CAR) targeted against the CD19 antigen have demonstrated impressive responses when adoptively transferred to patients with advanced chronic lymphocytic leukemia. The general concept of the CAR T cell was devised some 20 years ago. In this relatively short period of time, the technology to redirect T-cell function has moved at pace facilitating clinical translation; however, many questions remain with respect to developing the approach to improve CAR T-cell therapeutic activity and also to broaden the range of tumors that can be effectively targeted by this approach. This review highlights some of the underlying principles and compromises of CAR T-cell technology using the CD19-targeted CAR as a paradigm and discusses some of the issues that relate to targeting solid tumors with CAR T cells.     

Association between PD-1/PD-L1 and T regulate cells in early recurrent miscarriage

In this study, we try to testify the relationship between the programmed cell death receptor-1 (PD-1)/programmed cell death ligand 1 (PD-L1) passway and Treg cells in maternal-fetal immune regulation through PD-1 blockade on lymphocytes of normal early pregnancy in vitro and investigation of the PD-1 and PD-L1 changes in early recurrent miscarriage patients. CD4+ CD25+ Treg cells and PD-1 (CD279) positive cell were detected in deciduas in early recurrent miscarriage patients by flow cytometry. And the normal early pregnant women were as controls. Meanwhile the mRNA level of PD-1 and molecular expression of PD-L1 in deciduas of early recurrent miscarriage patients were detected by real time RT-PCR test and Immunohistochemical staining respectively. Also through antibody blocking assay to block PD-1 on lymphocytes of normal early pregnancy in vitro further testify the relationship between PD-1/PD-L1 and Treg cells, the results were analyzed by flow cytometry. CD4+ CD25+ Treg cells decreased both in deciduas in RM (P < 0.05), and for all almost 100% Treg cells (CD4+ CD25+) expressed PD-1, but there was no difference between the PD-1 positive cells in decidual lymphocytes in RM and that in normal pregnancy women (P > 0.05). PD-L1 mRNA in deciduas decreased in RM (P < 0.001), but PD-1 mRNA no difference (P > 0.1). After PD-1 blockade there was no change in CD4+ CD25+ Treg cells percentage, while the CD4+ T cell percentage increased (P < 0.01), as well as the level of IFN-gamma in cells supernatant (P < 0.01). PD-1 blockade has a little influence on the number of Treg cells, and may lead to impaired Treg cells function, the decrease of PD-L1 may closely relates to the occurrence of early recurrent miscarriage and implies that Treg cells may through PD-1/PD-L1 pathway play a role of immunosuppression regulation, and the impairment of Treg cells function in recurrent early abortion cases may be due to PD-L1 decrease in deciduas or trophoblast cells rather than PD-1 change.     

Chimeric antigen receptor-modified human regulatory T cells that constitutively express IL-10 maintain their phenotype and are potently suppressive

Clinical trials of Treg therapy in transplantation are currently entering phases IIa and IIb, with the majority of these employing polyclonal Treg populations that harbor a broad specificity. Enhancing Treg specificity is possible with the use of chimeric antigen receptors (CARs), which can be customized to respond to a specific human leukocyte antigen (HLA). In this study, we build on our previous work in the development of HLA-A2 CAR-Tregs by further equipping cells with the constitutive expression of interleukin 10 (IL-10) and an imaging reporter as additional payloads. Cells were engineered to express combinations of these domains and assessed for phenotype and function. Cells expressing the full construct maintained a stable phenotype after transduction, were specifically activated by HLA-A2, and suppressed alloresponses potently. The addition of IL-10 provided an additional advantage to suppressive capacity. This study therefore provides an important proof-of-principle for this cell engineering approach for next-generation Treg therapy in transplantation.     

MDR1基因沉默增强三尖杉酯碱诱导的HT9细胞凋亡

目的: 探讨靶向P-糖蛋白(又称多药耐药蛋白1,MDR1)基因的shRNA对三尖杉酯碱诱导人耐三尖杉酯碱的前髓细胞白血病HT9细胞凋亡的影响。方法: 构建MDR1 基因特异的shRNA表达载体pSilencer 3.1-H1 neo-MDR1,稳定电转染HT9细胞,实时荧光定量PCR分析MDR1 mRNA的表达,Western blotting检测细胞MDR1蛋白表达,MTT法检测细胞活力,经三尖杉酯碱处理后琼脂糖凝胶电泳检测凋亡细胞DNA片段化,激光共聚焦观察细胞形态变化,流式细胞术检测细胞周期变化。结果: 成功构建了shRNA表达载体pSilencer 3.1-H1 neo-MDR1,稳定转染后,HT9细胞MDR1 mRNA和蛋白表达均显著降低, HT9细胞三尖杉酯碱的 IC₅₀由(1.184±0.130)mg/L降至(0.711±0.010)mg/L。与HT9细胞相比,经三尖杉酯碱处理后稳定转染细胞HT9/sh-3.1-1的DNA ladder更明显,激光共聚焦显微镜下可见形态不规则的碎片状或梅花状等典型的细胞凋亡形态;细胞的S期细胞增多,并出现明显的凋亡峰。结论: shRNA表达载体pSilencer 3.1-H1 neo-MDR1能够稳定、持久地抑制MDR1 基因,并有效增强三尖杉酯碱诱导的HT9细胞凋亡。     

Clinical Utilization of Chimeric Antigen Receptor T Cells in B Cell Acute Lymphoblastic Leukemia: An Expert Opinion from the European Society for Blood and Marrow Transplantation and the American Society for Blood and Marrow Transplantation

On August 30, 2017 the US Food and Drug Administration approved tisagenlecleucel (Kymriah; Novartis, Basel, Switzerland), a synthetic bioimmune product of anti-CD19 chimeric antigen receptor T cells (CAR-T), for the treatment of children and young adults with relapsed/refractory B cell acute lymphoblastic leukemia (B-ALL). With this new era of personalized cancer immunotherapy, multiple challenges are present, ranging from implementation of a CAR-T program to safe delivery of the drug, long-term toxicity monitoring, and disease assessments. To address these issues experts representing the American Society for Blood and Marrow Transplant, the European Society for Blood and Marrow Transplantation, the International Society of Cell and Gene Therapy, and the Foundation for the Accreditation of Cellular Therapy formed a global CAR-T task force to identify and address key questions pertinent for hematologists and transplant physicians regarding the clinical use of anti CD19 CAR-T therapy in patients with B-ALL. This article presents an initial roadmap for navigating common clinical practice scenarios that will become more prevalent now that the first commercially available CAR-T product for B-ALL has been approved.     

In vivo anti-tumor activity of murine hematopoietic stem cells expressing a p185HER2-specific chimeric T-cell receptor gene

We have confirmed efficient anti-tumor activities of the peripheral lymphocytes transduced with a p185HER2-specific chimeric T-cell receptor gene both in murine and in human in our previous studies. To further test the feasibility of chimeric T-cell receptor in a bone marrow transplantation model, we first, made two murine tumor cell lines: MT901 and MCA-205, to express human p185HER2 by retroviral gene transduction. Murine bone marrow cells were retrovirally transduced to express the chimeric T-cell receptor and gene-modified bone marrow cells were transplanted into lethally irradiated mouse. Six months post transplantation, p185HER2-positive tumor cells:MT-901/HER2 or MCA-205/ HER2 was subcutaneously or intravenously injected to make mouse models simulating primary breast cancer or pulmonary metastasis. The in vivo anti-tumor effects were monitored by the size of the subcutaneous tumor or counting the tumor nodules in the lungs after India ink staining. The size of the subcutaneous tumor was significantly inhibited and the number of pulmonary nodules were significantly decreased in mouse recipients transplanted with chimeric T-cell receptor modified bone marrow cells compared with the control group. Our results suggest the efficient in vivo anti-tumor activities of chimeric T-cell receptor gene modified bone marrow cells.     

Building a Safer and Faster CAR: Seatbelts,Airbags, and CRISPR

Therapeutic T cell engineering has recently garnered widespread interest because of the success of CD19 chimeric antigen receptor (CAR) therapy. CARs are synthetic receptors for antigen that redirect the specificity and reprogram the function of the T cells in which they are genetically introduced. CARs targeting CD19, a cell surface molecule found in most leukemias and lymphomas, have yielded high remission rates in patients with chemorefractory, relapsed disease, including acute lymphoblastic leukemia, chronic lymphocytic leukemia, and non-Hodgkin lymphoma. The toxicities of this treatment include B cell aplasia, cytokine release syndrome (CRS), and neurotoxicity. Although reversible in most instances, these toxicities may require specific medical interventions, including transfer to intensive care to treat severe CRS. Guidelines for managing these toxicities are emerging. The recent report of a nonhuman primate model for CRS is poised to help advance the management of this syndrome. Finally, new engineering modalities, based on the use of targeted nucleases like CRISPR, may further enhance the efficacy and safety of CAR T cells.     

Building a CAR Garage: Preparing for the Delivery of Commercial CAR T Cell Products at Memorial Sloan Kettering Cancer Center

Two commercial chimeric antigen receptor (CAR) T cell therapies for CD19-expressing B cell malignancies, Kymriah and Yescarta, have recently been approved by the Food and Drug Administration. The administration of CAR T cells is a complex endeavor involving cell manufacture, tracking and shipping of apheresis products, and management of novel and severe toxicities. At Memorial Sloan Kettering Cancer Center, we have identified 8 essential tasks that define the CAR T cell workflow. In this review, we discuss practical aspects of CAR T cell program development, including clinical, administrative, and regulatory challenges for successful implementation.     

Suboptimal recognition of a T cell epitope of the major dog allergen Can f 1 by human T cells

We have previously proposed that mammalian lipocalin allergens are recognized suboptimally by the human immune system due to their homology with endogenous lipocalins. Here, we have characterized in detail the human T cell recognition of one of the previously identified T cell epitopes of the major dog allergen Can f 1, contained in peptide p105–120. A panel of peptide analogues (altered peptide ligands, APLs) of p105–120 was tested on two specific T cell clones restricted by different human leukocyte antigen (HLA) alleles. Interestingly, we identified for both of the clones several heteroclitic APLs that were capable of stimulating them at 10–30-fold lower concentrations than the natural peptide. Moreover, one of the heteroclitic APLs identified with the T cell clones, L115F, was observed to induce a stronger polyclonal T cell response than the natural allergen peptide from the peripheral blood mononuclear cells (PBMCs) of six Can f 1-allergic subjects studied. The heteroclitic APLs bound with the same affinity as p105–120 to common HLA-DR- and HLA-DP-alleles, suggesting that their improved stimulatory capacity is attributable to a more efficient T cell receptor (TCR) recognition rather than increased HLA binding. Collectively, our data suggest that p105–120 is recognized suboptimally by human T cells. This may contribute to the allergenicity of Can f 1.