T细胞过继免疫治疗技术的研究进展

随着科学技术的发展和治疗理念的转变,以免疫治疗为基础的肿瘤生物疗法作为现代肿瘤治疗的第四种模式,越来越受到重视,应用前景广阔。相比起传统的手术和放化疗,这种方法毒副作用小、安全稳定,适应性广泛,其原理是通过利用现代生物技术调     

多发性骨髓瘤T细胞免疫治疗

多发性骨髓瘤(multiple myeloma,MM)是一种目前难以治愈的恶性浆细胞肿瘤,近年来蛋白酶体抑制剂和免疫调节剂的应用明显改善了治疗效果,但大部分MM患者最终难以逃脱复发的结局.越来越多的证据表明经体外活化或基因修饰的T细胞能在体内特异性的杀伤肿瘤细胞,有望治愈MM,尤其是近年来嵌合抗原受体修饰T细胞(chimeric antigen receptor-modified T cells,CAR-T)的发展,其能在体内以非MHC限制性方式特异杀伤表达特定抗原的肿瘤细胞,为MM的治疗提供了新的思路.本文将讨论T细胞免疫治疗的发展和技术改进,就目前较有前景的几种T细胞治疗方法做一综述.     

基因修饰T细胞肿瘤过继免疫治疗安全性的研究进展

基因修饰T细胞(CAR-T,TCR-T)赋予其肿瘤靶向性、更强的杀伤活性和持久的生命力,在恶性血液肿瘤和实体瘤的临床试验中取得了可喜的效果.然而,不断积累的的临床资料也发现了安全性担忧:炎症细胞因子级联反应引发的肿瘤靶向毒性;抗原识别相关的脱靶效应、非肿瘤靶向效应、移植物抗宿主病等,不仅难以预见而且复杂难治,促使研究人员以毒性发生机制为切入点,尝试应用自杀基因开关、细胞内凋亡酶调控、分离式CAR受体、抑制性CAR受体等调控策略,实现对基因修饰T细胞时间和空间的精准控制,预防毒性反应的发生.本文综述基因修饰T细胞的安全问题及应对策略.     

嵌合抗原受体修饰T细胞免疫治疗肿瘤的研究进展

以嵌合抗原受体(chimeric antigen receptor,CAR)修饰T细胞为基础的肿瘤过继细胞免疫治疗近年来取得了很大的进步,它赋予T细胞靶向杀伤活性,并可克服肿瘤局部免疫抑制微环境和打破宿主免疫耐受状态。CAR以单链抗体-共刺激分子-免疫受体酪氨酸活化基序的嵌合模式修饰T细胞显示出良好的抗肿瘤作用,Ⅰ/Ⅱ期临床试验在白血病、淋巴瘤等恶性肿瘤中取得了令人鼓舞的治疗效果;CAR修饰T细胞临床治疗也带来了挑战,比如脱靶效应、细胞因子风暴、移植物抗宿主病样损伤等。研究者正在通过安装人工基因调控系统、优化共刺激分子、筛选最佳治疗潜质的T细胞亚群来提高CAR修饰T细胞的有效性和安全性,相信随着研究的不段深入,基于CAR的免疫治疗新策略会给肿瘤患者带来新的希望。     

基于嵌合抗原受体修饰T细胞的血液肿瘤过继性免疫治疗新进展:第56届美国血液学会年会报道

靶向识别特异抗原的嵌合抗原受体修饰T细胞(CAR-T细胞)已成为治疗恶性血液病的有效手段.临床研究涉及多种多样的CAR设计、不同的生产工艺及研究群体等.CAR-T细胞治疗慢性淋巴细胞白血病(CLL)和急性淋巴细胞白血病(ALL)已取得了令人瞩目的疗效,这将有可能改变所有类型血液系统恶性肿瘤的治疗模式.第56届美国血液学会(ASH)年会中关于CAR-T细胞的研究结果鼓舞了人们对这类新型治疗策略的信心.文章介绍CAR-T细胞治疗的临床研究结果和应用前景.虽然CAR-T细胞治疗恶性血液病还存在着许多有待解决的问题,但其治疗的高反应率促使开展了更多的临床研究.     

基于嵌合抗原受体修饰T细胞的肿瘤免疫治疗新策略

嵌合抗原受体（chimeric antigen receptor,CAR）修饰T细胞是近年来迅速发展的肿瘤过继免疫治疗新手段,其独特的作用机制和诱人的应用前景为肿瘤生物治疗开辟了一个崭新的舞台。CAR将识别肿瘤相关抗原的单链抗体和T细胞的活化基序相结合,通过基因转导赋予T细胞肿瘤靶向性、更强的杀伤活性和持久的生命力。自1989年Eshhar等首次提出CAR以来,CAR已从第一代发展至含有共刺激分子的第二、三代,CAR的Ⅰ/Ⅱ期临床试验在白血病、淋巴瘤、黑素瘤等恶性肿瘤中取得了可喜的成果,但是也面临脱靶效应、细胞因子风暴、移植物抗宿主病等潜在的安全性问题,未来研究将集中于设计更安全的第四代CAR、甄选具备最佳治疗潜质的T细胞亚群、优化临床治疗方案、完善临床前试验模型等方面。相信随着免疫学、基因治疗和细胞工程等领域不断取得新突破,CAR从实验室向临床转化的障碍将会逐一扫除,CAR有望成为主流的肿瘤治疗方法。     

过继性T细胞治疗在非小细胞肺癌中的研究进展

T细胞是获得性抗肿瘤免疫的重要细胞亚群,但肿瘤组织中的T细胞数量少,且处于免疫抑制甚至耗竭状态,这是导致肿瘤免疫逃逸和免疫检查点抑制剂等抗肿瘤免疫治疗效果不佳的重要原因。过继性T细胞治疗主要包括肿瘤浸润淋巴细胞（tumor-infiltrating lymphocytes,TILs）、嵌合抗原受体T细胞（chimeric antigen receptor T-cell,CAR-T）、T细胞受体工程化T细胞（T-cell receptor engineering T cell,TCR-T）治疗,其通过体外筛选扩增富集肿瘤特异性T细胞或通过基因改造赋予T细胞新的抗原特异性（CAR-T、TCR-T）,有效克服了肿瘤浸润T细胞不足的缺陷。虽然过继性T细胞治疗在非小细胞肺癌（non-small cell lung cancer,NSCLC）中的研究起步较晚,但已显示治疗的安全可行性和初步抗肿瘤效果,值得进一步深入研究。本文将对TILs、CAR-T、TCR-T的原理、培养方法、生物学特征以及在NSCLC治疗中的研究进展进行综述,以期为优化临床研究设计和开展新型NSCLC免疫治疗提供新思路。      

CAR-T细胞在肿瘤治疗中的机遇与挑战

近年来,嵌合抗原受体基因修饰T（CAR-T）细胞作为“活的药物”在血液肿瘤治疗中取得了令人振奋的效果,成为肿瘤治疗新的发展方向,得到了医学界广泛的认可。纵观免疫细胞治疗技术的发展历程,任何一项新的治疗手段从实验室到临床应用都需要一个不断完善的过程,CAR-T细胞治疗技术同样如此。虽然它在血液系统恶性肿瘤的治疗中显示出前所未有的疗效,如对晚期复发难治性急性淋巴细胞白血病（ALL）治疗的完全缓解(CR)可达到90%,对慢性淋巴细胞白血病（CLL）和部分B细胞淋巴瘤的CR达到50%以上,但目前CAR-T细胞疗法在血液肿瘤的治疗过程中尚存在脱靶效应、毒副作用、体内持续时间短、复发率高等问题;在CAR-T细胞治疗实体瘤方面,其安全性和有效性已得到证实,但疗效还有待提高。针对上述问题,笔者总结出提高CAR-T细胞治疗效果的六大策略：（1）克服患者本身T细胞的缺陷;（2）选择CAR-T细胞的最佳培养条件;（3）制定靶细胞刺激的最佳方案;（4）确定化疗预处理的方案;（5）实现CAR的人源化;（6）加强共刺激信号的组合。本文对近年来CAR-T细胞治疗技术的研究进展及该领域中亟需解决的问题作一分析与展望。     

嵌合抗原受体T细胞治疗实体瘤的研究进展和挑战

随着嵌合抗原受体疗法在血液系统癌症中的惊人疗效,研究者们也在实体瘤方面展开探索。我们将回顾近年来嵌合抗原受体T细胞（CAR-T）治疗卵巢癌、肺癌、肝癌等实体瘤的研究进展;还将对CAR-T细胞治疗实体瘤的局限性,即抗原特异性问题、CAR-T细胞贩运问题以及肿瘤微环境问题结合相应对策进行综述。     

调节性T细胞与恶性肿瘤的过继免疫治疗

过继免疫治疗利用自身免疫细胞进行体外扩增培养,然后回输到体内,它通过增强机体免疫力来对抗肿瘤,对肿瘤细胞具有靶向杀伤性作用,是最有可能彻底清除手术或放化疗后残存肿瘤细胞的治疗手段.但是,调节性T细胞(Regulatory T cells,Tregs)在多种恶性肿瘤患者外周血及微环境中普遍存在着比例上调的情况,这不仅会导致机体固有免疫的负性平衡,还会影响过继免疫治疗的疗效,使其不能发挥最大的抗肿瘤作用.通过对Tregs日渐深入的了解,人们已经研究出多种抑制及消除Tregs的治疗策略.     

Rebuilding human leukocyte antigen class II-restricted minor histocompatibility antigen specificity in recall antigen-specific T cells by adoptive T cell receptor transfer: implications for adoptive immunotherapy.

PURPOSE: Donor T cells directed to hematopoietic minor histocompatibility antigens (mHag) are appealing tools for adoptive immunotherapy of hematological malignancies after allogeneic stem cell transplantation (allo-SCT). Toward the development of a convenient strategy for ex vivo generation of human leukocyte antigen (HLA) class II--restricted mHag-specific T cells, we evaluated the feasibility of rebuilding mHag-specific T cell functions in donor-derived recall antigen-specific T cells via T cell receptor (TCR) transfer. EXPERIMENTAL DESIGN: TCR alpha- and beta-chains of an HLA-DPB1*0401--restricted T-cell clone recognizing a multiple myeloma-associated mHag were retrovirally transferred into a tetanus toxoid (TT)--specific clone derived from the original stem cell donor. TCR double-transduced cells were compared with the parent mHag- and TT-specific clones for antigen specificity, cytokine secretion, and cytotoxic activity and were analyzed for their in vitro expansion capacity in a TT- or mHag-specific fashion. RESULTS: mHag-TCR--transduced TT-specific cells displayed both TT and mHag specificity. Similar to the parent cells, they secreted Th-1 cytokines and exerted significant cytotoxic activity against TT-pulsed or mHag(+) target cells, including multiple myeloma cells. A 4-week expansion of TCR-transduced cells via the TT-specific TCR had no negative influence on the mHag-specific cytotoxic activity and resulted in 10- to 100-fold better cell yields as compared with mHag-specific expansion. CONCLUSIONS: HLA class II--restricted, mHag-specific effector functions can be successfully reconstructed in donor-derived TT-specific T cells via TCR transfer. Effective expansion of these T cells via TT-specific TCRs illustrate the suitability of this strategy for ex vivo expansion and possibly for in vivo TT-specific reboosting of HLA class II--restricted immunotherapeutic T cells.     

Strategies of antigen-specific T-cell-based immunotherapy for cancer

The critical role of antigen-specific T-cells in the eradication of cancer has been demonstrated in numerous animal models, while significant challenges need to be conquered before antigen-specific T-cell immunotherapy can achieve true success in clinical practice. These challenges include: (1) weak or nonimmunogenicity of spontaneous tumors, (2) negative immune regulation mechanisms of the host immune system, (3) immune inhibition exerted by tumor cells, (4) physical barrier in solid tumor, and (5) escape or resistance to immune attack by tumor cells. Nonetheless, significant success has been achieved in several clinical trials recently, highlighting the possibility of successful manipulation of the immune system for control and elimination of tumor. We focused our study on summarizing the current knowledge and corresponding strategies for improving autologous cytotoxic T-cell (CTL)-based cancer immunotherapy, which include the following aspects: (1) the selection of tumor antigens for stimulation of CTL, (2) strategies of enhancing maturation and antigen presentation activity of dendritic cells (DC), (3) strategies of activation and maintenance of CTL response, and (4) recruitment of suitable immune effector cells to tumor sites. The successful manipulation of the immune system, based on the more and more detailed knowledge of tumor immunology, may finally reach the goal of "immune surveillance of malignancy."     

Isolation and expansion of allogeneic myeloma-specific interferon-gamma producing T cells for adoptive immunotherapy

Adoptive immunotherapy is a promising approach in the treatment of multiple myeloma. We have tested the identification, separation, and expansion of allogeneic myeloma-specific T cells in vitro. Irradiated myeloma cell line ARH 77 has been used to stimulate allogeneic CD4⁺ and CD8⁺ T lymphocytes. Activated myeloma-specific T cells that produced interferon-gamma were isolated using immunomagnetic beads and further expanded in vitro to numbers of up to 400×106 T cells. Specificity of the T lymphocytes was tested using a 5-(6-)carboxyfluoresceine diacetate succinimidyl ester (CFSE)—based cytotoxicity test. This study demonstrates the feasibility of identification and isolation of tumor-specific T cells from allogeneic donors that can be expanded in vitro to numbers useful for clinical applications.     

乳腺癌过继性细胞免疫治疗的研究进展

目前国际上取得重大进展的四类过继性细胞免疫治疗(ACT)技术主要包括肿瘤浸润淋巴细胞(TIL)、CAR-T细胞、TCR-T细胞和CAR-NK细胞治疗。乳腺癌相关研究结果表明,TIL能预测乳腺癌的预后,间质TIL增加与良好的预后相关;CAR-T细胞免疫治疗在血液系统肿瘤治疗中取得巨大突破后,现已用于靶向实体肿瘤治疗,并在乳腺癌的治疗中开展了多种靶点的临床试验;TCR-T细胞疗法依赖于MHC,可以识别MHC分子呈递的任何抗原,具有更广泛的靶抗原,在治疗实体瘤方面更有前景,多项乳腺癌TCR-T细胞治疗临床试验正在进行中;CAR-NK细胞治疗是通过借鉴CAR-T细胞的结构而设计的,具有出色的抗肿瘤能力,比CAR-T细胞疗法更安全,可能将为肿瘤免疫治疗带来新的更大发展。ACT在乳腺癌的研究和临床应用领域仍具挑战,其中TIL疗法难以产生足量的特异性T细胞,CAR-T和CAR-NK细胞疗法均不同程度存在细胞的持久性、快速归巢到肿瘤床、毒性和转导效率等问题。尽管存在不足,但随着基因工程、肿瘤免疫学和分子生物学等多学科的迅速发展,相信ACT技术有望为乳腺癌患者治疗带来新的希望。     

癌相关CD8+记忆T细胞在过继免疫治疗中的应用

针对癌症患者的过继免疫治疗是临床肿瘤治疗研究中的热点话题。癌症患者体内天然存在着能够对恶性肿瘤细胞进行识别、攻击和杀伤的癌相关CD8+记忆T细胞,它们具有对少量肿瘤细胞产生快速免疫应答和持续长期发挥抗癌作用的优点。癌相关CD8+记忆T细胞主要存在于骨髓中,如将骨髓中的这部分T细胞分离出来,并以特定手段激活并回输体内,将可发挥强大的免疫治疗作用。为了帮助临床癌症治疗研究者们更加清晰地认识癌相关CD8+记忆T细胞的生物学特性、肿瘤杀伤能力和临床治疗效果,并妥善处理实际应用过程中遇到的各种问题,本文对近年有关癌相关CD8+记忆T细胞在肿瘤免疫治疗中应用的研究进展加以介绍。     

T cell adoptive immunotherapy of newly diagnosed gliomas.

Patients with newly diagnosed gliomas were treated with adoptive transfer of ex vivo activated T lymphocytes, derived from lymph nodes (LNs) draining autologous tumor vaccines, to determine the long-term toxicity of this treatment. Twelve consecutive patients were enrolled: 2 with grade II astrocytoma, 4 with anaplastic gliomas, and 6 with glioblastoma multiforme. Patients were injected intradermally with short-term cultured autologous irradiated tumor cells, admixed with granulocyte macrophage colony-stimulating factor, to stimulate draining LNs. The LN cells were activated with staphylococcal enterotoxin A for 48 h and then cultured in medium containing interleukin 2 for an additional 6-8 days and subsequently transferred i.v. to the patients. The number of cells obtained from the LNs ranged from 9 x 10(7) to 1.1 x 10(9), and the median cell proliferation was 41-fold. The dose of T cells infused ranged from 0.6 to 5.5 x 10(10) with a median of 1.1 x 10(10), the majority of which were CD 4+ (mean, 71%). The entire treatment was performed as outpatient therapy and was associated with a toxicity of grade 2 or less, consisting mainly of fever, nausea, and myalgias during the first 24 h. There were no indications of late adverse events from this treatment even among three patients with follow-up greater than 2 years post T cell transfer. Moreover, four patients demonstrated partial regression of residual tumor. This Phase I clinical trial of adoptive immunotherapy for patients with newly diagnosed malignant gliomas demonstrates feasibility, lack of long-term toxicity, and several objective clinical responses.     

Generation and application of human induced‐stem cell memory T cells for adoptive immunotherapy

Adoptive T‐cell therapy is an effective strategy for cancer immunotherapy. However, infused T cells frequently become functionally exhausted, and consequently offer a poor prognosis after transplantation into patients. Adoptive transfer of tumor antigen‐specific stem cell memory T (T_SCM) cells is expected to overcome this shortcoming as T_SCM cells are close to naïve T cells, but are also highly proliferative, long‐lived, and produce a large number of effector T cells in response to antigen stimulation. We previously reported that activated effector T cells can be converted into T_SCM‐like cells (iT_SCM) by coculturing with OP9 cells expressing Notch ligand, Delta‐like 1 (OP9‐hDLL1). Here we show the methodological parameters of human CD8⁺ iT_SCM cell generation and their application to adoptive cancer immunotherapy. Regardless of the stimulation by anti‐CD3/CD28 antibodies or by antigen‐presenting cells, human iT_SCM cells were more efficiently induced from central memory type T cells than from effector memory T cells. During the induction phase by coculture with OP9‐hDLL1 cells, interleukin (IL)‐7 and IL‐15 (but not IL‐2 or IL‐21) could efficiently generate iT_SCM cells. Epstein–Barr virus‐specific iT_SCM cells showed much stronger antitumor potentials than conventionally activated T cells in humanized Epstein–Barr virus transformed‐tumor model mice. Thus, adoptive T‐cell therapy with iT_SCM offers a promising therapeutic strategy for cancer immunotherapy.