Effects of adoptive T-cell immunotherapy on immune cell profiles and prognosis of patients with unresectable or recurrent cholangiocarcinoma

The identification of immune cell profiles (ICP) involved in anti-tumor immunity is crucial for immunotherapy. Therefore, we herein investigated cholangiocarcinoma patients (CCA) who received adoptive T-cell immunotherapy (ATI). Eighteen unresectable or recurrent CCA received ATI of αβ T cells alone or combined with chemotherapy. ICP were evaluated by flow cytometry. There were 14 patients with intrahepatic cholangiocarcinoma (iCCA) and four with distal cholangiocarcinoma (dCCA). After one course of treatment, nine iCCA and four dCCA had progressive disease (PD), while five iCCA had stable disease (SD). Median overall survival (OS) was prolonged to 21.9 months. No significant differences were observed in OS between the PD and SD groups of iCCA. The frequency of helper T cells (HT) in iCCA decreased from 70.3% to 65.5% (P = .008), while that of killer T cells (KT) increased from 27.0% to 30.6% (P = .005). dCCA showed no significant changes of immune cells. OS was prolonged in iCCA with increased frequencies of CD3+ T cells (CD3) (P = .039) and αβ T cells (αβ) (P = .039). dCCA showed no immune cells associated with OS. The frequencies of CD3+ T cells and αβ T cells in the PD group for iCCA decreased from 63.5% to 53% (P = .038) and from 61.6% to 52.2% (P = .028), respectively. In the SD group, the frequency of HT decreased from 65.8% to 56.9% (P = .043), whereas that of KT increased from 30.1% to 38.3% (P = .043). In conclusions, ATI affected ICP and prolonged OS. Immune cells involved in treatment effects differed according to the site of cholangiocarcinoma.

Personalized adoptive immunotherapy for patients with EBV-associated tumors and complications: Evaluation of novel naturally processed and presented EBV-derived T-cell epitopes

Morbidity and mortality of immunocompromised patients are increased by primary infection with or reactivation of Epstein-Barr virus (EBV), possibly triggering EBV⁺ post-transplant lymphoproliferative disease (PTLD). Adoptive transfer of EBV-specific cytotoxic T cells (EBV-CTLs) promises a non-toxic immunotherapy to effectively prevent or treat these complications. To improve immunotherapy and immunomonitoring this study aimed at identifying and evaluating naturally processed and presented HLA-A*03:01-restricted EBV-CTL epitopes as immunodominant targets. More than 15000 peptides were sequenced from EBV-immortalized B cells transduced with soluble HLA-A*03:01, sorted using different epitope prediction tools and eleven candidates were preselected. T2 and Flex-T peptide-binding and dissociation assays confirmed the stability of peptide-MHC complexes. Their immunogenicity and clinical relevance were evaluated by assessing the frequencies and functionality of EBV-CTLs in healthy donors (n > 10) and EBV⁺ PTLD-patients (n = 5) by multimer staining, Eli- and FluoroSpot assays. All eleven peptides elicited EBV-CTL responses in the donors. Their clinical applicability was determined by small-scale T-cell enrichment using Cytokine Secretion Assay and immunophenotyping. Mixtures of these peptides when added to the EBV Consensus pool revealed enhanced stimulation and enrichment efficacy. These EBV-specific epitopes broadening the repertoire of known targets will improve manufacturing of clinically applicable EBV-CTLs and monitoring of EBV-specific T-cell responses in patients.

Epstein-Barr virus-specific adoptive immunotherapy for recurrent, metastatic nasopharyngeal carcinoma

BACKGROUND

Early-stage and intermediate-stage nasopharyngeal cancer (NPC) generally carry a good prognosis, but for patients with recurrent, metastatic disease, options are limited. In the current study, the authors present a phase 1/2 study to evaluate the efficacy of Epstein-Barr virus (EBV)-stimulated cytotoxic T-lymphocyte (EBV-CTL) immunotherapy in this patient population.

METHODS

Screening for patients with active, recurrent, metastatic EBV-associated NPC began in February 2007, and the study was closed to accrual in January 2012. After informed consent was obtained, patients had their blood drawn to initiate manufacturing of the EBV-CTL product. During product manufacturing, patients were placed on interim standard-of-care chemotherapy, and only after disease progression on the interim chemotherapy did patients receive investigational immunotherapy. Patients were restaged every 2 months until disease progression and then followed for survival.

RESULTS

A total of 28 patients were enrolled, and 21 patients were treated. There was 1 complete response achieved, and at the time of last follow-up, the patient had been in remission for >8 years since treatment. The median progression-free survival was 2.2 months, and the median overall survival was 16.7 months. Two other patients, after failing EBV-CTL immunotherapy, unexpectedly demonstrated strong responses to the chemotherapy regimens they had previously failed. Patient EBV viral load and EBV-CTL specificity for tumor-associated viral antigens did not appear to correlate with clinical response.

CONCLUSIONS

A durable response was observed with EBV-CTL immunotherapy, but the overall response rate for patients with recurrent, metastatic NPC was low. Further research is necessary to increase the efficacy of EBV-specific immunotherapy in patients with incurable NPC, and to characterize mechanisms for refacilitation to chemotherapy. Cancer 2017;123:2642-50. © 2017 American Cancer Society.

Strategies and developments of immunotherapies in osteosarcoma

Osteosarcoma (OS) is a frequently observed primary malignant tumor. Current therapy for osteosarcoma consists of comprehensive treatment. The long-term survival rate of patients exhibiting nonmetastatic OS varies between 65-70%. However, a number of OS cases have been observed to be resistant to currently used therapies, leading to disease recurrence and lung metastases, which are the primary reasons leading to patient mortality. In the present review, a number of pieces of evidence provide support for the potential uses of immunotherapy, including immunomodulation and vaccine therapy, for the eradication of tumors via upregulation of the immune response. Adoptive T-cell therapy and oncolytic virotherapy have been used to treat OS and resulted in objective responses. Immunologic checkpoint blockade and targeted therapy are also potentially promising therapeutic tools. Immunotherapy demonstrates significant promise with regard to improving the outcomes for patients exhibiting OS.

Selective immunotargeting of diabetogenic CD4 T cells by genetically redirected T cells

The key role played by islet-reactive CD8 and CD4 T cells in type 1 diabetes calls for new immunotherapies that target pathogenic T cells in a selective manner. We previously demonstrated that genetically linking the signalling portion of CD3-ζ onto the C-terminus of β2 -microglobulin and an autoantigenic peptide to its N-terminus converts MHC-I complexes into functional T-cell receptor-specific receptors. CD8 T cells expressing such receptors specifically killed diabetogenic CD8 T cells, blocked T-cell-induced diabetes in immunodeficient NOD.SCID mice and suppressed disease in wild-type NOD mice. Here we describe the immunotargeting of CD4 T cells by chimeric MHC-II receptors. To this end we chose the diabetogenic NOD CD4 T-cell clone BDC2.5, which recognizes the I-A(g7) -bound 1040-31 mimotope. We assembled several constructs encoding I-A(g7) α- and β-chains, the latter carrying mim or hen egg lysozyme peptide as control, each supplemented with CD3-ζ intracellular portion, either with or without its transmembrane domain. Following mRNA co-transfection of reporter B3Z T cells and mouse CD8 and CD4 T cells, these constructs triggered robust activation upon I-A(g7) cross-linking. A BDC2.5 T-cell hybridoma activated B3Z transfectants expressing the mimotope, but not the control peptide, in both configurations. Potent two-way activation was also evident with transgenic BDC2.5 CD4 T cells, but peptide-specific activation required the CD3-ζ transmembrane domain. Chimeric MHC-II/CD3-ζ complexes therefore allow the selective immunotargeting of islet-reactive CD4 T cells, which take part in the pathogenesis of type 1 diabetes.