Successful induction of tumor-specific cytotoxic T lymphocytes from patients with non-small cell lung cancer using CD80-transfected autologous tumor cells.

Cytotoxic T lymphocytes (CTL) against human lung cancer cells are difficult to induce by a conventional method using tumor cell stimulation probably due to an insufficiency of tumor antigens (TA) or costimulatory molecules such as CD80. We, therefore, investigated the potential of CD80-transfected tumor cells as stimulators of the in vitro induction of autologous tumor-specific CTL from regional lymph node lymphocytes in patients with lung cancer. Five non-small cell lung cancer cell lines (two adenocarcinomas, 1 squamous cell carcinoma, 1 large cell carcinoma and 1 adenosquamous cell carcinoma) were established from surgical specimens and were successfully transduced with a plasmid constructed with expression vector pBj and human CD80 cDNA, using a lipofection method. CD80-transfected tumor cells (CD80-AT) significantly augmented the proliferation of autologous lymphocytes from all cases as compared with non-transfected tumor cells (AT). AT-stimulated lymphocytes from 4 out of 5 cases did not show any cytotoxicity against AT; however, lymphocytes stimulated with CD80-AT exhibited substantial cytotoxicity against parental AT in all 5 cases tested. AT-stimulated lymphocytes derived from only one out of 5 cases showed major histocompatibility complex (MHC)-class I-restricted cytokine production in response to AT, while the MHC-class I-restricted responses were found in CD80-AT-stimulated lymphocytes from 4 out of 5 cases. These results indicate that CD80 on tumor cells could be a beneficial costimulatory molecule to elicit CTL against lung cancer, and also show that TA recognized by CTL was frequently expressed on lung cancer cells.     

Induction of anti-leukemic cytotoxic T lymphocytes by fusion of patient-derived dendritic cells with autologous myeloblasts

Presentation of AML antigens by dendritic cells (DC) could potentially induce a T cell-mediated anti-leukemic immune response. In the present study, we generated DC from adherent (AD-DC) and non-adherent (NAD-DC) myeloblasts obtained from bone marrows of AML patients. Both cell populations displayed morphological, phenotypic and functional properties of DC. The functions of NAD-DC were compared to AD-DC that had been fused with autologous AML blasts (FC/AML). The FC/AML induced greater T cell proliferation and CTL activity against autologous AML blasts (9/10 cases) as compared to NAD-DC. FC/AML may thus represent a promising strategy for DC-based immunotherapy of patients with AML.     

自体宫颈癌-树突细胞疫苗激活的CTL杀伤效应

背景与目的:树突细胞(dendriticcells,DC)是目前已知的功能最强的抗原递呈细胞(antigen-presentingcell,APC),它可以在体内、外向T淋巴细胞递呈抗原,并诱发细胞毒T淋巴细胞(cytotoxicTlymphocyte,CTL)反应。本研究旨在探讨负载自体宫颈癌抗原的DC体外激发的CTL对自体宫颈癌细胞的杀伤效应。方法:先冻融宫颈癌细胞制备抗原,然后以GM-CSF、IL-4诱导自体外周血单个核细胞(peripheralbloodmononuclearcell,PBMC)获得DC并负载抗原,刺激自体T淋巴细胞制备宫颈癌抗原特异性CTL,观察CTL对宫颈癌细胞的杀伤活性。结果:负载自体宫颈癌抗原DC诱导的特异性CTL对自体宫颈癌细胞的体外杀伤率高达79.32%～89.27%,显著高于淋巴因子激活的杀伤细胞(lymphokine-activatedkillingcells,LAK)的杀伤率(t≥2.89,P<0.05);且对宫颈癌HeLa细胞株具有一定杀伤效应(40.35%～58.09%),但低于自体癌细胞组(t≥2.97,P<0.05);特异性CTL对HepG2、MCF7、A549、MGC803细胞无明显杀伤效应。结论:自体宫颈癌-树突细胞疫苗体外诱导的CTL具有高效而特异的抗自体宫颈癌细胞免疫活性,可望成为宫颈癌生物治疗的一个有力手段。     

Dendritic cells loaded with killed breast cancer cells induce differentiation of tumor-specific cytotoxic T lymphocytes

Background

Early clinical trials, mostly in the setting of melanoma, have shown that dendritic cells (DCs) expressing tumor antigens induce some immune responses and some clinical responses. A major difficulty is the extension to other tumors, such as breast carcinoma, for which few defined tumor-associated antigens are available. We have demonstrated, using both prostate carcinoma and melanoma as model systems, that DCs loaded with killed allogeneic tumor cell lines can induce CD8⁺ T cells to differentiate into cytotoxic T lymphocytes (CTLs) specific for shared tumor antigens.

Methods

The present study was designed to determine whether DCs would capture killed breast cancer cells and present their antigens to autologous CD4⁺ and CD8⁺ T cells.

Results

We show that killed breast cancer cells are captured by immature DCs that, after induced maturation, can efficiently present MHC class I and class II peptides to CD8⁺ and CD4⁺ T lymphocytes. The elicited CTLs are able to kill the target cells without a need for pretreatment with interferon gamma. CTLs can be obtained by culturing the DCs loaded with killed breast cancer cells with unseparated peripheral blood lymphocytes, indicating that the DCs can overcome any potential inhibitory effects of breast cancer cells.

Conclusion

Loading DCs with killed breast cancer cells may be considered a novel approach to breast cancer immunotherapy and to identification of shared breast cancer antigens.

     

Immunotherapy of metastatic renal cell carcinoma with tumor lysate-pulsed autologous dendritic cells.

PURPOSE: We wanted to evaluate feasibility and safety of dendritic cell-based immunotherapy in patients with metastatic renal cell carcinoma (RCC). EXPERIMENTAL DESIGN: Patients with metastatic RCC (n = 35) received vaccinations (i.v. or i.d.) of CD83+ autologous monocyte-derived dendritic cells (moDCs). MoDCs were loaded with lysate of cultured autologous or allogeneic permanent tumor cells (A-498) as well as keyhole limpet hemocyanin as control and helper antigen. Maturation of moDCs was induced by a combination of tumor necrosis factor alpha, interleukin 1 beta, interleukin 6, and prostaglandin E2. RESULTS: Treatment was associated with transient flu-like symptoms. In 2 of 27 evaluable patients, any evidence of disease disappeared (complete response). In both cases, metastatic tissue had been the source of tumor antigen. One patient had an objective partial response. Seven patients had stable disease, the remaining 17 patients had progressive disease. In 11 of 11 patients evaluated, moDCs induced strong immune responses against keyhole limpet hemocyanin. In 5 of 6 patients tested, enhanced immune responses against oncofetal antigen (immature laminin receptor; OFA/LRP) could also be detected. The strongest responses against OFA/LRP were detectable in 2 patients with complete response and partial response, respectively. At the time of submission, mean follow up is 32 months and 8 patients are currently alive. CONCLUSIONS: Our data indicate that moDC-based vaccination is well tolerated and has immunological as well as clinical effects in patients with metastatic RCC. OFA/LRP might be an attractive candidate antigen for DC-based immunotherapy of RCC.     

Induction of autologous tumor-specific cytotoxic T cells in patients with liver cancer. Characterizations and clinical utilization.

To generate autologous-tumor-specific cytotoxic T cells (CTL), peripheral blood mononuclear cells (PBMC) obtained from cancer patients were cultivated with autologous tumor cells for 5 days, and restimulated with interleukin-2 for another 5 days. Subsequently, their cytotoxic activity was examined by an in vitro cytotoxic test as well as by Winn's assay utilizing nude mouse transplanted autologous tumors. The present results demonstrated that these in vitro-stimulated cells were able to kill autologous tumor cells but not allogeneic tumors, and that they also inhibited the growth of transplanted autologous tumors in the nude mouse. Their cytotoxic activity was completely abrogated by pre-treatment with either anti-CD3 or anti-CD8, but not with anti-CD4, plus complement. Based on these studies, we injected these CTL via the hepatic artery into patients having either nonresected tumors or recurrent tumors in the liver. Among 15 treated patients (13 with hepatocellular carcinoma and 2 with metastatic liver cancer) 2 complete responses, 3 partial responses and 4 minor responses were observed. During the 6 to 25 months following injection of CTL, no definite signs of tumor recurrence or regrowth were demonstrated in these 5 responding patients (complete plus partial).     

Activation of autologous or HLA-identical sibling cytotoxic T lymphocytes by blood derived dendritic cells pulsed with tumor cell extracts.

This study describes the effect of dendritic cells (DC) pulsed with tumor cell extracts on the induction and activation of autologous and HLA-identical sibling tumor cell specific cytotoxic T lymphocytes (CTL). The subjects of the study were patients with hematological malignancies (acute myeloid leukemia, acute lymphoblastic leukemia, and multiple myeloma), and stem cell transplant donors. Although lymphocytes primed with non-pulsed DC did not show definite cytotoxic activity against autologous or HLA-identical sibling patient tumor cells, both autologous and HLA-identical sibling CTL activated by DC pulsed with tumor cell extracts demonstrated markedly significant killing activity against tumor cells in the fashion of higher cytotoxicity with the increase of effector:target ratio (p<0.05). These findings reveal that DC pulsed with tumor cell extracts could be efficiently applicable in anti-tumor immunotherapy for patients with hematological malignancies.     

Induction of tumor-specific cytotoxic T lymphocytes from regional lymph node lymphocytes of human breast cancer

Background  In this study we activated breast cancer-specific cytotoxic T lymphocytes (CTL) from regional lymph node lymphocytes (RLNL) of HLA-A2-positive patients with breast cancer. Melthods  Freshly isolated RLNL were stimulated with solid phase anti-CD3 monoclonal antibody followed by expansion with recombinant interleukin-2. Subsequently, the RLNL were stimulated with an irradiated HLA 0201 breast cancer cell line, MCF-7, at a responder/stimulator ratio of 10/1 once a week for 2 weeks. Results  The cultured RLNL exhibited specific lysis against MCF-7 in all 5 HLA-A2-positive patients tested, but not in 2 HLA-A2-negative patients. Cytotoxicity against MCF-7 was substantially inhibited by addition of anti-HLA-A2 mAb. In 3 of 5 HLA-A2-positive patients, anti-MCF-7 CTL also exhibited a substantial level of reactivity against PC-9, an HLA-A0206-positive lung adenocarcinoma cell line. Conversely, anti-PC-9-specific CTL were inducible by multiple stimulations of RLNL with PC-9 cells in 2 of 3 patients. Conclusions  These results suggest that several common tumor antigens might exist among HLA-A2-positive breast cancers, some of which may be shared with lung adenocarcinomas.     

Induction of tumour-specific CD8(+) cytotoxic T lymphocytes by tumour lysate-pulsed autologous dendritic cells in patients with uterine serous papillary cancer

Uterine serous papillary carcinoma is a highly aggressive variant of endometrial cancer histologically similar to high grade ovarian cancer. Unlike ovarian cancer, however, it is a chemoresistant disease from onset, with responses to combined cisplatinum-based chemotherapy in the order of 20% and an extremely poor prognosis. In this study, we demonstrate that tumour lysate-pulsed autologous dendritic cells can elicit a specific CD8(+) cytotoxic T lymphocyte response against autologous tumour target cells in three patients with uterine serous papillary cancer. CTL from patients 1 and 2 expressed strong cytolytic activity against autologous tumour cells, did not lyse autologous lymphoblasts or autologous EBV-transformed cell lines, and were variably cytotoxic against the NK-sensitive cell line K-562. Patient 3 CD8(+) T cells expressed a modest but reproducible cytotoxicity against autologous tumour cells only at the time of the first priming. Further priming attempts with PBL collected from patient 3 after tumour progression in the lumboaortic lymph nodes were unsuccessful. Cytotoxicity against autologous tumour cells could be significantly inhibited by anti-HLA class I (W6/32) and anti-LFA-1 MAbs. Highly cytotoxic CD8(+) T cells from patients 1 and 2 showed a heterogeneous CD56 expression while CD56 was not expressed by non-cytotoxic CD8(+) T cells from patient 3. Using two colour flow cytometric analysis of intracellular cytokine expression at the single cell level, a striking dominance of IFN-gamma expressors was detectable in CTL populations of patients 1 and 2 while in patient 3 a dominant population of CD8(+) T cells expressing IL-4 and IL-10 was consistently detected. Taken together, these data demonstrate that tumour lysate-pulsed DC can be an effective tool in inducing uterine serous papillary cancer-specific CD8(+) CTL able to kill autologous tumour cells in vitro. However, high levels of tumour specific tolerance in some patients may impose a significant barrier to therapeutic vaccination. These results may have important implications for the treatment in the adjuvant setting of uterine serous papillary cancer patients with active or adoptive immunotherapy.     

Tumor-derived heat shock protein 70-pulsed dendritic cells elicit tumor-specific cytotoxic T lymphocytes (CTLs) and tumor immunity

Vaccination with autologous tumor-derived heat shock proteins (Hsp), such as Hsp70, Hsp90 and gp96, has been demonstrated to elicit specific immune responses against the tumor from which the Hsps were isolated. The effect of Hsp immunization is wholly dependent on the presence of functional antigen-presenting cells (APCs) in the immunized host, and Hsp receptors on APCs have recently been identified. Here we show that bone marrow-derived dendritic cells (DCs) are able to internalize HSP-peptide complex and that peptides are re-presented by DCs via the major histocompatibility complex (MHC) class I presentation pathway. In addition, immunization with tumor-derived HSP-pulsed DCs induces strong cytotoxic T cell (CTL) responses against multiple antigenic peptides in a transporter-associated antigen processing (TAP)-dependent manner. The results of the present study provide strong evidence of an efficient cross-priming activity of Hsp70, which could be exploited in the development of new and more effective immunotherapeutic strategies for cancer patients. (Cancer Sci 2004; 95: 248–253)     

Distribution of autologous tumor-specific cytotoxic T lymphocytes in human metastatic melanoma.

The study of specific immunity in human cancers has been hampered by the elusive distribution and heterogeneity of effector cells. In this study, we have investigated the distribution of autologous melanoma-specific cytotoxic T lymphocytes (CTLs) in 18 different distant metastases from melanomas (9 non-visceral and 9 visceral metastases). Uncultured cells from tumors were provided directly for the establishment of T-cell clones using limiting dilution analysis to avoid any possible effects of in vitro sensitization of T cells to coexisting tumor cells. Autologous tumor specific CTL clones were detected in 6 of 18 tumors (33%, 4 non-visceral and 2 visceral metastases). The majority of CTL clones (35 of 46 and 17 of 19) in 2 patients with HLA class-I A2 haplotype failed to lyse either A2+ or A2- allogeneic melanoma cells, although anti-class-I (monomorphic) MAb inhibited their cytotoxicity. The remaining 11 of 46 and 2 of 19 CTL clones showed A2-restricted cytotoxicity. Autologous tumor-specific cytotoxicity was also detected after polyclonal culture of these tumor-infiltrating lymphocytes (TILs) in 8 of 16 tumors (50%, 5 non-visceral and 3 visceral metastases). These results suggest that tumor-specific T cells exist at tumor sites in at least one-third of distant metastases of melanomas and could be induced by the addition of IL-2 in at least half of the tumors. Tumor-specific T cells were detectable more often in non-visceral than in visceral metastases.     

癌胚抗原重组痘苗病毒转染树突状细胞诱导CEA特异性T细胞免疫

 目的　研究人癌胚抗原重组痘苗病毒 (rV CEA)转染树突状细胞 (DC)在体外诱导CEA特异性的T细胞免疫。方法　将rV CEA转染外周血单个核细胞来源的DC后用于激发自体的T细胞 ,通过对T细胞的增殖及杀伤功能的检测 ,与野生型痘苗病毒 (V 76 1)转染的DC激发的T细胞进行比较。结果　经rV CEA转染的DC激活的T细胞增殖力强 ,对CEA分泌性肿瘤细胞具特异性杀伤作用。结论　rV CEA转染的DC可以诱导CEA特异性T细胞活性。     

负载腮腺腺样囊性癌抗原的树突状细胞诱导的抗肿瘤效应

目的：探讨腺样囊性癌肿瘤抗原负载的树突状细胞通过淋巴细胞介导的免疫反应,体外杀伤腺样囊性癌细胞的细胞毒性效应。方法：外周血单核细胞在GM—CSF＋IL-4的诱导下体外培养,用肿瘤细胞抗原冲击后,流式细胞仪检测树突状细胞抗原负载前后CD1a、CD83表达量的变化。MTT比色法检测同种异体的混合淋巴细胞反应和诱导细胞毒淋巴细胞CTL杀伤肿瘤细胞。结果：凋亡肿瘤抗原刺激后,CD83表达增加（P〈0．01）,而CD1a表达量下调（P〈0．05）。负荷肿瘤抗原树突状细胞体外诱导出明显的细胞不良反应,并刺激同种T淋巴细胞增殖。结论：GM—CSF＋IL-4诱导的单核细胞来源的树突状细胞,能在体外摄取肿瘤抗原而进一步成熟,通过激活淋巴细胞杀伤癌细胞。     

Induction of tumor immunity and cytotoxic T lymphocyte responses using dendritic cells transfected with messenger RNA amplified from tumor cells

Unique patient-specific tumor antigens may constitute the dominant antigens in the antitumor immune response. Hence, vaccination with the patient's own repertoire of tumor antigens may offer a superior strategy to elicit protective immunity. We have shown previously that dendritic cells transfected with mRNA isolated from tumor cells stimulate potent CTL responses and engender protective immunity in tumor-bearing mice. In the current study, we demonstrate that tumor mRNA, isolated from murine tumor cell lines or from primary human tumor cells microdissected from frozen tissue sections, can be amplified without loss of function. This study provides the foundations for an effective and broadly applicable treatment that does not require the characterization of the relevant antigenic profile in each patient and will not be limited by tumor tissue availability for antigen preparation.     

Generation of anti-p53 cytotoxic T lymphocytes from human peripheral blood using autologous dendritic cells.

CTLs recognizing the HLA-A2.1-restricted, wild-type sequence p53 epitopes p53(149-157) and p53(264-272) were generated from CD8-enriched populations of nonadherent peripheral blood lymphocytes (PBLs) obtained from healthy donors. The PBLs were restimulated in vitro with peptide-pulsed granulocyte macrophage colony-stimulating factor- and interleukin (IL)-4-induced autologous dendritic cells in the presence of IL-6 and IL-12 and subsequently cultivated with IL-1alpha, IL-2, IL-4, IL-6, and IL-7. Bulk anti-p53(264-272) CTL populations were generated from PBLs obtained from two of five donors. Both CTL populations were cytotoxic against peptide-pulsed HLA-A2+ target cells, but not against untreated target cells. A CD8+ anti-p53 CTL clone designated p264#2 was isolated from one of the bulk populations. It was found to have an intermediate affinity of approximately 10(-9) M for the epitope and to mediate cytotoxicity against several human tumor cell lines, including the squamous cell carcinoma of the head and neck cell line SCC-9, which is known to present the wild-type sequence p53(264-272) epitope. In addition, CTLs reactive against p53(149-157)-pulsed targets as well as a HLA-A2+ tumor cell line were cloned from a bulk population of antitumor CTLs obtained from one of the five normal PBLs restimulated with this epitope. The results indicate that CTLs recognizing wild-type sequence epitopes can be generated from precursors present in PBLs obtained from some normal individuals using autologous dendritic cells as antigen-presenting cells and suggest that vaccine strategies targeting these epitopes can lead to antitumor CTL generation, thereby emphasizing the therapeutic potential of p53-based cancer vaccines.     

Rapid generation of potent and tumor-specific cytotoxic T lymphocytes by interleukin 18 using dendritic cells and natural killer cells

We hypothesized that antitumor-specific immunity, which is induced by interleukin (IL) 18 treatment in murine tumor models, is promoted by enhancing natural killer (NK)-mediated destruction of tumor and delivery to dendritic cells (DCs). These activated and antigen-pulsed DCs then critically and optimally induce an adoptive immune response, positioning IL-18 as an important bridge between the innate and adoptive immune response. The effect of IL-18 added to cultures of live tumor cells (MCA205, a mouse sarcoma cell line), NK cells, DCs, and T cells was assessed. When recombinant (r) mIL-18 protein was added to this culture, potent NK cytolytic activity with subsequent generation of CTLs was observed in a dose-dependent manner. Without introduction of either rmIL-18 or NK cells into this culture, systemic cytolytic activity was significantly decreased. Following the absence of direct contact of either NK cells or DCs with other cells in this cooperative coculture system using transwell, the systemic cytolytic activity of both NK cells and CTLs was greatly suppressed. The cytolysis mediated by effector cells harvested after completion of the culture was primarily restricted to MHC class I and highly specific for the tumor cells used in the coculture. Furthermore, we examined the efficiency in the induction of cytolytic T cells of other established IFN-gamma inducing T-cell growth factors, IL-2, and IL-12 in this culture system and compared them with that mediated by IL-18. Neither IL-2 nor IL-12 induced tumor-specific cytolytic T cells to the same degree as that mediated by IL-18. Efficacy of this system in induction of tumor-specific CTLs was also observed in the system using MC38 adenocarcinoma cells. These results are consistent with the notion that IL-18 induces tumor-specific immunity through enhancing NK activity, which in turn mediates tumor cell death and activates and primes DCs.     

Tumor lysate and IL-18 loaded dendritic cells elicits Th1 response,tumor-specific CD8+ cytotoxic T cells in patients with malignant glioma

In this study, we demonstrate that tumor lysate-loaded dendritic cells can elicit a specific CD8+ cytotoxic T lymphocyte response against autologous tumor cells in patients with malignant glioma. CTL from three of five patients expressed strong cytolytic activity against autologous glioma cells, did not lyse autologous lymphoblasts and were variably cytotoxic against the LAK-sensitive cell line Daudi. Also, DCs pulsed normal brain lysate failed to induce cytolytic activity against autologous glioma cells, suggesting the lack of autoimmune response. Two of five patients CD8+ T cells expressed a modest cytotoxicity against autologous glioma cells. CD8+ T cells isolated during these ineffective primings secreted large amounts of IL-10, less amounts of IFN-γ as detected by ELISA, Type 2 bias in the CD8+ T cell response accounts for the lack of cytotoxic effector function from these patients. Cytotoxicity against autologous glioma cells could be significantly inhibited by anti-HLA class I antibody. These data demonstrate that tumor lysate-loaded DC can be an effective tool in inducing glioma-specific CD8+ CTL able to kill autologous glioma cells in vitro. However, high levels of tumor specific tolerance in some patients may account for a significant barrier to therapeutic vaccination. Moreover, cytotoxic responses were augmented by transfecting DC with the gene for IL-18. For all five patients, CD8+T cells treated with IL18 transfected DC produced Th1 response. These results may have important implications for the treatment of malignant glioma patients with immunotherapy. DCs loaded with total tumor lysate and IL-18 may represent a method for inducing Th1 immunoresponses against the entire repertoire of glioma antigens.     

体外扩增肾癌患者自体NK细胞及其对人肾细胞癌786-O细胞的杀伤

目的:探究IL-15、4-1BBL基因修饰的人白血病K562细胞(modi-K562细胞)联合IL-2体外高效扩增肾细胞癌患者自体自然杀伤(natural killer,NK)细胞的方法,研究扩增前后NK细胞对肾癌细胞株786-O的杀伤作用。方法:10例肾癌患者的外周血单个核细胞(peripheral blood mononuclear cell,PBMC)与modi-K562细胞在含不同浓度IL-2培养液中共育14 d,采用流式细胞术、Calcein-AM释放实验检测NK细胞的扩增情况、免疫表型及对肾癌786-O细胞的杀伤作用。结果:modi-K562细胞联合IL-2可有效扩增NK细胞,300 U/ml IL-2培养14 d时,NK细胞扩增(202.4±12.8)倍。在效靶比为20∶1时,扩增后NK细胞对786-O细胞的杀伤率为(72.0±4.3)%,显著高于扩增前NK细胞的杀伤率(34.2±3.6)%(P<0.01)。结论:IL-15、4-1BBL基因修饰的K562细胞联合IL-2在体外能有效扩增肾细胞癌患者NK细胞,扩增后NK细胞对肾癌786-O细胞的杀伤作用显著增强。