过继性细胞基因疗法与类风湿关节炎

类风湿关节炎(Rheumatoid arthritis,RA)是一种常见的以滑膜炎及关节软骨破坏为特征的累及全身多关节的慢性自身免疫性疾病,患病率及致残率高,严重影响患者的健康和生活质量,给家庭和社会带来沉重的负担。目前,RA的病因仍不十分明确,针对的治疗选择很有限,其治疗方法主要依靠药物治疗,血浆置换,造血干细胞移植及外科手术治疗等。且目前最好的治疗方法都不能从根本上改变RA患者的病情状态。所以治疗RA需要一个新颖的方法-过继性细胞基因疗法。本文就RA治疗现状和进展作一综述,并对各种方法比较其利弊。

细胞基因疗法在视网膜退行性疾病中的应用和挑战

视网膜退行性疾病的治疗是多年困扰眼科临床工作者的棘手问题。细胞基因疗法(CGT)是国内外生物医药产业未来发展的主要方向之一。CGT产品运用了生物技术的前沿创新技术,这类产品给现阶段医学无法解决的疾病带来了极大的希望。CGT有望成为治疗视网膜退行性疾病的潜在疗法。本文中笔者总结和评述了CGT应用于视网膜退行性疾病的可行性和安全性,并进行相关信息的扩展。

Angiostatin基因治疗人肝癌裸鼠移植瘤的实验研究

目的:研究Angiostatin基因治疗对人肝癌裸鼠皮下移植瘤的抑制作用及其相关机理。方法:使用人原发性肝癌细胞株SMMC-7721建立人肝癌裸鼠皮下移植瘤动物模型,质粒用脂质体DOTAP介导转染细胞。将荷瘤裸鼠随机分为两组,分别注射质粒PcDNA3、Angiostatin/PcDNA3,观察两组动物的肿瘤生长曲线,检测肿瘤的Angiostatin、VEGF、HIF-1α表达和微血管密度(MVD),利用TUNEL染色法行原位细胞凋亡分析。结果:Angiostatin基因治疗在早期具有抑制肿瘤生长的作用,大约1周后肿瘤以更快的速度生长并迅速赶上空质粒对照组肿瘤;Angiostatin基因治疗组的肿瘤组织中有An-giostatin的局部高表达,MVD(24.8±2.8)低于空质粒对照组(30.2±4.1)(P〈0.05)。肿瘤组织中HIF-1α蛋白局部高表达,VEGF表达高于空质粒对照组,细胞凋亡指数(2.87±0.48)高于空质粒对照组(1.55±0.43)(P〈0.01)。结论:Angiostatin基因治疗对人肝癌裸鼠皮下移植瘤的生长具有一定的抑制作用,肿瘤对Angiostatin基因治疗可以产生耐受性。

TCR-T过继免疫疗法及其在妇科肿瘤中的研究进展

T细胞受体基因工程改造的T细胞(TCR-T)是一种新兴肿瘤过继免疫疗法,是从肿瘤患者体内鉴定出含有肿瘤抗原特异性的TCR,在体外经T细胞扩增、克隆和分选提取出目标TCR基因序列;将TCR基因序列与载体结合并侵染宿主体内T细胞,得到TCR基因工程改造的T细胞对肿瘤细胞起到特异性免疫效果,最终达到杀灭肿瘤细胞治疗肿瘤的目的。在目前,该疗法在妇科肿瘤领域的应用仍处于临床Ⅰ、Ⅱ期临床试验阶段,已显示出较好的安全性和可行性;但是,目前已经完成的临床试验样本总量较小,患者疗效和预后因所用方法不同而存在较大差异,其安全性和有效性仍在检验过程中。

整合位点分析技术的研究进展

慢病毒载体已被广泛用于将外源DNA转移到人类细胞中治疗各种遗传疾病。慢病毒载体可以整合到宿主基因组中,但整合位点通常不可预测,这可能会增加其治疗效果的不确定性。随着基因及细胞疗法的广泛应用,监管机构出台了一系列技术指导文件,以确保产品持续的安全性。整合位点分析(integration site analysis,ISA)是通过表征基因治疗载体的整合图谱来评估其生物安全性,也是转基因细胞进行克隆跟踪的关键工具。概述了用于逆转录病毒整合位点的技术演变,以及信息分析工具的优势和发展趋势,总结了减低病毒随机整合至基因组中的应对策略,以期为慢病毒载体的整合位点分析检测和细胞治疗产品新药临床试验安全性评估提供参考。

输液袋无菌灌装的新方案

安全、无菌地将含有活性成分的生物药品和新的基因和细胞疗法产品装入输液袋——这是制药行业的一项新挑战。正因如此,专家们在这一领域获得的进展都是非常重要的案例。近期,Harro Höfliger推出了新的输液袋无菌灌装方法,以期为制药企业提供更全面的无忧包装。

全球首个用于输血依赖的β⁃地中海贫血的基因疗法Zynteglo

Zynteglo(betibeglogene autotemcel)是2022年8月17日被美国FDA批准的全球首个用于需要定期输血的成人和儿童β⁃地中海贫血患者的基因疗法。Zynteglo是一种一次性的基因治疗产品,以单剂量给药。Zynteglo每个剂量都是使用患者自身来源的CD_(34)^(+)骨髓造血干细胞创建的定制治疗,这些造血干细胞经过体外的基因改造后进行自体移植,在体内分化成能够产生功能性血红蛋白的红细胞,从而达到治疗β⁃地中海贫血的目的。本文从该疗法的慢病毒载体和作用机制、非临床研究、临床有效性研究、临床安全性研究、适用人群和使用方法以及注意事项6个方面对该基因疗法进行全面介绍。

TCR T细胞疗法的研究挑战和审评考虑

随着生物技术的发展,细胞基因疗法已成为生物制药领域的新热点。2017和2018年,Kymriah(Novartis公司)和Yescarta(Kite Pharma)两款嵌合抗原受体(chimeric antigen receptor,CAR)T细胞治疗产品在美国和欧盟相继上市,推动了CAR T细胞疗法的研发热潮。与此同时,国内外多家企业已在研发与CAR T细胞疗法同属于细胞基因疗法的T细胞受体(T cell receptor,TCR)T细胞疗法。

个体化肿瘤特异TCR的筛选策略

基因修饰T细胞疗法在肿瘤治疗领域取得突破性进展,主要包括嵌合抗原受体基因修饰T(chimeric antigen receptor engineered T,CAR-T)细胞和T细胞受体基因修饰T(T-cell receptor modified T,TCR-T)细胞。虽然CAR-T细胞疗法在血液系统肿瘤治疗领域呈现良好的临床治疗效果,但CAR-T细胞仅能识别肿瘤细胞膜抗原(占细胞全部抗原的比例约10%),而TCR-T细胞可以识别人白细胞抗原(human leukocyte antigen,HLA)提呈的细胞内抗原,因此TCR-T细胞可以识别更多种类的肿瘤抗原,进而实现对CAR-T细胞的合理补充。由于TCR-T细胞需要同时识别细胞内抗原和对应的HLA,而不同患者的HLA分型和表达的肿瘤抗原都可能存在巨大差异,因此有必要为每个/每类肿瘤患者定制个体化的TCR-T细胞,其中的关键为筛选特异识别肿瘤抗原的TCR。当前主要有筛选靶向“已知”肿瘤抗原TCR和筛选靶向“未知”肿瘤抗原TCR的两种策略,但其各有适用性,应针对每个患者制定适合的筛选方法,以制备多种肿瘤特异性TCR-T细胞,从而实现个体化TCR-T细胞的肿瘤治疗。

ShRNA-mediated gene silencing of β-catenin inhibits growth of human colon cancer cells

AIM: To observe the gene silencing mediated by the specific shRNA targeted against β-catenin and its effect on cell proliferation and cycle distribution in the human colon cancer cell line Colo205. METHODS: Two shRNA plasmid vectors against β-catenin were constructed and transfected into Colo205 cells with LipofectamineTM2000. The down-regulations of β-catenin, c-myc and cyclinD1 expressions were detected by RT-PCR and western blot analysis. The cell proliferation inhibitions were determined by MTT assay and soft agar colony formation assay. The effect of these two β-catenin shRNAs on cell cycle distribution and apoptosis was examined by flow cytometry. RESULTS: These two shRNA vectors targeted against β-catenin efficiently suppressed the expression of β-catenin and its down stream genes, c-myc and cyclinD1. The expression inhibition rates were around 40%-50% either at the mRNA or at the protein level. The shRNA-mediated gene silencing of β-catenin resulted in significant inhibition of cell growth both on the culture plates and in the soft agar. Moreover, the cancer cells showed significant G0/G1 arrest and increased apoptosis at 72 h post transfection due to gene silencing. CONCLUSION: These specific shRNAs targeted against β-catenin could have a gene silencing effect and block the WNT signaling pathway. They could inhibit cell growth, increase apoptosis, and induce cell cycle arrest in Colo205 cells. ShRNA interference against β-catenin is of potential value in gene therapy of colon cancer.

Retrovirus-mediated herpes simplex virus thymidine kinase gene therapy approach for hepatocellular carcinoma

The therapeutic effect of herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV) system on hepatocellular carcinoma was studied in this experiment. The tk-containing retroviral recombinants were used to infect hepatoma cells (BEL-7402) and the cells were treated with ganciclovir (0-1000 microg/ml). The results showed that HSV-tk gene could be efficiently transferred in vitro into hepatoma cells and stably expressed. The growth potential of the tk-containing cells was significantly inhibited by GCV (P

Paclitaxel induces apoptosis in human gastric carcinoma cells

AIM;To investigate the apoptosis in gastric cancer cells induced by paclitaxel,and the relation between this apoptosis and expression of Bcl-2 and Bax. METHODS:In in vitro experiments,MTT assay was used to determine the cell growth inhibitory rate.Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of gastric cancer cell line SGC-7901 before and after the paclitaxel treatment.Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2 and Bax. RESULTS:Paclitaxel inhibited the growth of gastric cancer cell line SGC-7901 in a dose-and time-dependent manner. Paclitaxel induced SGC-7901 cells to undergo apoptosis with typically apoptotic characteristics,including morphological changes of chromatin condensation,chromatin crescent formation,nucleus fragmentation and apoptotic body formation.Paclitaxel could reduce the expression of apoptosis-regulated gene Bcl-2,and improve the expression of apoptosis-regulated gene Bax. CONCLUSION:Paclitaxel is able to induce the apoptosis in gastric cancer.This apoptosis may be mediated by down- expression of apoptosis-regulated gene Bcl-2 and up- expression of apoptosis-regulated gene Bax.

Comparison of efficacy and toxicity between gemcitabine plus cisplatin and plus carboplatin in first-line treatment of advanced non-small cell lung cancer

Objective: To compare the efficacy and toxicity between gemcitabine plus cisplatin and plus carboplatin in first-line treatment of advanced non-small cell lung cancer (NSCLC). Methods: Gemcitabine 1000 mg/m2 iv, d1, 8; cisplatin 75 mg/m2 iv, d1, or 25 mg/m2 iv, d1-3; carboplatin AUC = 5 iv, d1; repeated every 21 days. Results: All 76 cases were available for objective response. Gemcitabine + cisplatin (GCis) group: among 33 cases, CR 1 case, PR 13 cases, MR 3 cases, SD 7 cases, PD 9 cases, response rate, disease control rate, time to progress (TTP), median survival time (MST) and 1-, 2-year survival rates were 42.42% (14/33), 72.73% (24/33), 5 months, 14 months and 66.67% (22/33), 12.12% (4/33), respectively; Gemcitabine + carboplatin (GCarb) group: among 43 cases, PR 13 cases, MR 11 cases, SD 7 cases, PD 12 cases, the results while comparing with those of GCis group were 30.23% (13/43), 72.09% (31/43), 4 months, 11 months and 48.84% (21/43), 2.33% (1/43), respectively. Among them, only MST between the two groups had significant statistic difference (χ2 = 2.45, P = 0.017). Mild to modest myelo-suppression as well as nausea and vomiting were observed. Conclusion: Both GCis and GCarb regimens had active and well-tolerated toxicity for advanced NSCLC. Cisplatin-based chemotherapy yields a substantial effective advantage over carboplatin-based regimens. Therefore, carboplatin and cisplatin are not equal-active and that cisplatin-based doublet regimens should remain the standard first-line therapy for patients with advanced NSCLC with good performance status.

Construction of genetically engineered macrophages expressing Smad6 and Smad7 genes with adeno-associated virus

Objective: To construct the genetically engineered macrophages expressing Smad6 and Smad7 genes with adeno-associated virus (AAV). Methods: The plasmids containing pcDNA3-Smad6/Flag and pcDNA3-Smad7/Flag were digested with BamHⅠ and XhoⅠ, respectively. Then the Smad6/Flag and Smad7/Flag gene segments obtained were cloned into plasmid pAAV-MCS respectively to construct the recombinant pAAV-Smad6/Flag and pAAV-Smad7/Flag plasmids. The resulting recombinant plasmids (pAAV-Smad6/Flag or pAAV-Smad7/Flag) or pAAV-LacZ plasmid were co-transfected into the HEK 293cells with pHelper and pAAV-RC by calcium-phosphate precipitation method. Recombinant AAV-2 viral particles were prepared from infected HEK293 cells and then were used to infect mouse macrophages. The expressions of Smad6 and Smad7 in macrophages were detected by immunocytochemical staining and expression of b-galactosidase was evaluated by X-gal staining. Results: The recombinant AAV vector containing Smad6 or Smad7 genes was successfully constructed. More than 95% macrophage cells expressed X-gal and Smad6 and Smad7 genes at 72 h after infection. Conclusion: These results indicate that the genetically engineered macrophages can express Smad6 and Smad7 proteins effectively, laying the foundation for the studies of TGF-β-induced diseases in vivo and highlighting the feasibility of macrophage-based gene therapy.

Gene therapy targeted to telomerase in HCC by AF-hTERT-TK/GCV

Objective： The aim of this study was to observe the affection of targeted therapy to plasmid AF-pGL3-hTERT-TK in HCC cell line HepG2. Methods： We constructed therapeutic plasmid pGL3-hTERT-TK （containing suicide gene TK that promoted by promoter of hTERT） and was conjugated with AF-liposome （a protein that can combine with the receptor ASPGR on HCC cell surface）. Then we transfected HCC cell line HepG2 and hepatic cell L02 with AF-pGL3-hTERT-TK, observed the effects of therapeutic plasmid AF-pGL3-hTERT-TK for HCC cell line growth and apoptosis in vitro by Flow cytometry and Tun- nel method. Results： Our results showed that TK gene was 1100 bp in plasmid pGL3-hTERT-TK. Plasmid pGL3-hTERT-TK can effectively transfect HCC cell HepG2 and the transfection rate was 8.91%. By recognizing and combining effects of recep- tor protein ASPGR on HCC cell surface the therapeutic plasmid AF-pGL3-hTERT-TK could easily enter into HCC cell HepG2 and induce its apeptosis. The apoptosis rate was 85.87% while only 8.65% in L02 cell. Four days after AF-pGL3-hTERT-TK transfected HepG2 was intervention by ganciclovir （GCV）, a lot of apeptotic bodies were found by Tunnel analysis, while little apoptotic body was found in hepatic cell L02. Conclusion： AF-pGL3-hTERT-TK can target to HCC cell line and induce it to apoptesis, almost has no influence on hepatic cell L02. AF-pGL3-hTERT-TK has the potential therapeutic effects for HCC.

Stable transfection of extrinsic Smac gene enhances apoptosis-inducing effects of chemotherapeutic drugs on gastric cancer cells

AIM: To explore the feasibility of enhancing apoptosis-inducing effects of chemotherapeutic drugs on human gastric cancer cells by stable transfection of extrinsic Smac gene. METHODS: After Smac gene was transferred into gastric cancer cell line MKN-45, subclone cells were obtained by persistent G_(418) selection. Cellular Smac gene expression was determined by RT-PCR and Western blotting. After treatment with mitomycin (MMC) as an apoptotic inducer, in vitro cell growth activities were investigated by trypan blue-staining method and MTT colorimetry. Cell apoptosis and its rates were determined by electronic microscopy, annexin V-FTTC and propidium iodide staining flow cytometry. Cellular caspase-3 protein expression and its activities were assayed by Western blotting and colorimetry. RESULTS: When compared with MKN-45 cells, the selected subclone cell line MKN-45/Smac had significantly higher Smac mRNA (3.12±0.21 vs 0.82±0.14, t=7.52, P＜0.01) and protein levels (4.02±0.24 vs0.98±0.11, t=8.32, P＜0.01). After treatment with 10 μg/mL MMC for 6-24 h, growth inhibition rate of MKN-45/Smac (15.8±1.2-54.8±2.9%) was significantly higher than that of MKN-45 (5.8±0.4-24.0±1.5%, t=6.42, P＜0.01). Partial MKN-45/Smac cancer cells presented characteristic morphological changes of apoptosis under the electronic microscope with an apoptosis rate of 36.4±2.1%, which was significantly higher than that of MKN-45 (15.2±0.8%, t=9.25, P＜0.01). Compared with MKN-45, caspase-3 expression levels in MKN-45/Smac were improved significantly (3.39±0.42 vs0.96±0.14, t=8.63, P＜0.01), while its activities were 3.25 times as many as those of MKN-45 (0.364±0.010 vs0.112±0.007, t=6.34, P＜0.01). CONCLUSION: Stable transfection of extrinsic Smac gene and its over-expression in gastric cancer cell line can significantly enhance cellular caspase-3 expression and activities, ameliorate apoptosis-inducing effects of mitomycin C on cancer cells, which is a novel strategy to improve chemotherapeutic effects on gastric cancer.

Keratinocyte growth factor gene therapy ameliorates ulcerative colitis in rats

AIM:To investigate the effect of keratinocyte growth factor(KGF) gene therapy in acetic acid-induced ulcerative colitis in rat model.METHODS:The colitis of Sprague-Dawley rats was induced by intrarectal infusion of 1 mL 5%(v/v) acetic acid.Twenty-four hours after exposed to acetic acid,rats were divided into three experimental groups:control group,attenuated Salmonella typhimurium Ty21a strain(SP) group and SP strain carrying human KGF gene(SPK) group,and they were separately administered orally with 10% NaHCO3,SP or SPK.Animals were sacrificed and colonic tissues were harvested respectively on day 3,5,7 and 10 after administration.Weights of rats,colonic weight/length ratio and stool score were evaluated.Histological changes of colonic tissues were examined by hematoxylin and eosin(HE) staining method.The expression of KGF,KGF receptor(KGFR) and TNF-α were measured either by enzyme-linked immunosorbent assay or Western blotting.Immunohistochemistry was used to detect the cellular localization of KGFR and Ki67.In addition,superoxide dismutase(SOD) activity and malondialdehyde(MDA) contents in the homogenate were measured.RESULTS:Body weight and colonic weight/length ratio were declined in SPK group compared with SP and control groups(body weight:272.78 ± 17.92 g vs 243.72 ± 14.02 g and 240.68 ± 12.63 g,P < 0.01;colonic weight/length ratio:115.76 ± 7.47 vs 150.32 ± 5.99 and 153.67 ± 5.50 mg/cm,P < 0.01).Moreover,pathological changes of damaged colon were improved in SPK group as well.After administration of SPK strain,KGF expression increased markedly from the 3rd d,and remained at a high level till the 10th d.Furthermore,KGFR expression and Ki67 expression elevated,whereas TNF-α expression was inhibited in SPK group.In the group administered with SPK,SOD activity increased significantly(d 5:26.18 ± 5.84 vs 18.12 ± 3.30 and 18.79 ± 4.74 U/mg,P < 0.01;d 7:35.48 ± 3.35 vs 22.57 ± 3.44 and 21.69 ± 3.94 U/mg,P < 0.01;d 10:46.10 ± 6.23 vs 25.35 ± 4.76 and 27.82 ± 6.42 U/mg,P < 0.01) and MDA contents decreased accordingly(d 7:7.40 ± 0.88 vs 9.81 ± 1.21 and 10.45 ± 1.40 nmol/mg,P < 0.01;d 10:4.36 ± 0.62 vs 8.41 ± 0.92 and 8.71 ± 1.27 nmol/mg,P < 0.01),compared with SP and control groups.CONCLUSION:KGF gene therapy mediated by attenuated Salmonella ameliorates ulcerative colitis induced by acetic acids,and it may be a safe and effective treatment for ulcerative colitis.

Distribution and clonality of peripheral blood TCR Vα subfamily T cells in patients with acute promyelocytic leukemia

Objective： To investigate the distribution and clonality of TCR Va subfamily T cells in patients with acute promyelocytic leukemia （APL）. Methods： The complementary determining region 3 （CDR3） of TCR Va 29 subfamily genes in peripheral blood mononuclear cells from 9 APL patients were amplified using RT-PCR. The positive products were further analyzed to identity the clonality of T cells by GeneScan technique. Results： One to seven of TCR Va subfamilies could be detected in peripheral blood T cells from 9 cases with APL, the frequent expression of Va subfamilies predominated in Vα3 and Va19. Clonal expanded T cells could be detected in 8 APL patients, which predominant used Va3, Va26 or Va27 （3 out of 8 cases）. However, almost all Va subfamilies with polyclonal expansion could be detected in peripheral blood T cells from 10 cases of normal individuals. Conclusion： Remarkable skew distribution and clonal expansion of TCR Va subfamilies T cells is the common feature in patients with APL. Clonal expansion of T cells might reflect a response in host to APL cell associated antigen, whether these expanded T cells have the ability for specific cytotoxicity against APL cells, remains an open question.

A Study on the expression of erbB4/HER4 in non-small cell lung cancer

Objective: To test the expression of HER4 in non-small cell lung cancer (NSCLC) and elucidate the relationship between its over-expression and the clinical pathology of NSCLC. Methods: 70 cases of paraffin-embedded tissues from informative NSCLC were tested for the expression of HER4 by means of immunohistochemical assay. Results: HER4 were overexpressed in NSCLC in 91.4%. The overexpression of HER4 correlated only with the lymph node metastasis, TNM staging and survival after operation. Conclusion: ErbB4 is one of the genes to regulate the growth of NSCLC in advanced stages and artificial interference of the overexpression of HER4 in NSCLC might be a good way for the treatment of NSCLC in advanced stages.

Acceleration of Immune Reconstitution after Bone Marrow Transplantation in Mice by Bone Marrow Stromal Cell Line Transfected with IL-6 Gene

To observe potential effect of the engineered bone marrow stromal cell line QXMSC1 secreting IL-6 (QXMSCIL-6) on accelerating immune reconstitution in syngeneic bone marrow transplantation in mice, QXMSC1 was transfected with the eukaryocytic expression vector pcDNAIL-6, which contained hIL-6 cDNA by liposome-mediated gene transfecting technique. G418-resistance clone was selected by limiting dilution. The highest secreting clone was selected by ELISA assay and used in animal experiments. The recipient mice (BALB/c) were lethally irradiated and cotransplanted syngeneic bone marrow (10 7/mice) and the QXMSC1IL-6 (5×10 5/mice). Lymphocyte proliferation induced by ConA and LPS, helper T lymphocyte precursor (HTLp), cytotoxic T lymphocyte precursor (CTLp), plaque-forming cell (PFC), delayed type hypersensitivity (DTH) were examined 30, 60 days in post transplantation respectively. The results showed that lymphocytes proliferation to ConA and LPS, HTLp, CTLp increased, DTH and PFC were improved by cografted stromal cells QXMSC1IL-6 on 30, 60 days after BMT. These results demonstrated that the bone marrow stromal cell line QXMSC1IL-6 transfected with IL-6 (QXMSC1IL-6) accelerated immune reconstitution in syngeneic bone marrow transplantation.