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Purpose: Autologous monocyte-derived dendritic cells (DCs) electroporated with synthetic mRNA (TriMixDC-MEL) are immunogenic and have antitumor activity as a monotherapy in patients with pretreated advanced melanoma. Ipilimumab, an immunoglobulin G1 monoclonal antibody directed against the cytotoxic T-lymphocyte-associated protein 4 receptor that counteracts physiologic suppression of T-cell function, improves the overall survival of patients with advanced melanoma. This phase II study investigated the combination of TriMixDC-MEL and ipilimumab in patients with pretreated advanced melanoma., Patients and Methods: Thirty-nine patients were treated with TriMixDC-MEL (4 × 10(6) cells administered intradermally and 20 × 10(6) cells administered intravenously) plus ipilimumab (10 mg/kg every 3 weeks for a total of four administrations, followed by maintenance therapy every 12 weeks in patients who remained progression free). Six-month disease control rate according to the immune-related response criteria served as the primary end point., Results: The 6-month disease control rate was 51% (95% CI, 36% to 67%), and the overall tumor response rate was 38% (including eight complete and seven partial responses). Seven complete responses and one partial tumor response are ongoing after a median follow-up time of 36 months (range, 22 to 43 months). The most common treatment-related adverse events (all grades) consisted of local DC injection site skin reactions (100%), transient post-DC infusion chills (38%) and flu-like symptoms (84%), dermatitis (64%), hepatitis (13%), hypophysitis (15%), and diarrhea/colitis (15%). Grade 3 or 4 immune-related adverse events occurred in 36% of patients. There was no grade 5 adverse event., Conclusion: The combination of TriMixDC-MEL and ipilimumab is tolerable and results in an encouraging rate of highly durable tumor responses in patients with pretreated advanced melanoma., (© 2016 by American Society of Clinical Oncology.)

Dendritic cells (DCs) are bone marrow-derived professional antigen presenting cells. Due to their role as potent inducers of immune responses, these cells are widely used as adjuvant in experimental clinical settings for cancer immune therapy. We have developed a DC-based vaccine using autologous blood monocytes loaded with allogeneic tumor cell lysate rich in cancer/testis antigens. This vaccine has at present been tested for activity in three phase II clinical trials including two cohorts of patients with advanced colorectal cancer (CRC) and one cohort of patients with advanced non-small-cell-lung-cancer (NSCLC). In the present paper we retrospectively compare the maturation profile based on surface marker expression on DCs generated from the three patient cohorts and between cancer patient cohorts and a cohort of healthy donors. Vaccines were generated under cGMP conditions and phenotypic profiles of DC were analyzed by flow cytometry and the obtained data were used as a basis to set guideline values for our quality control of GMP produced DC vaccines. Each vaccine batch was analyzed for the expression of the surface maturation and differentiation molecules CD14, CD1a, CD83, CD86, MHC class II and CCR7, and the optimal expression pattern is considered as CD14(low), CD1a, CD83(high), CD86(high), MHC class II(high) and CCR7(high). In accordance with data from other studies including other types of cancer patients, especially breast cancer patients, we found that the maturation status of the DC batches depends on cancer type and correlates with clinical status of cancer patients included.

The clinical use of dendritic cells (DCs) to induce antigen-specific immune tolerance has been hampered by the lack of a widely acknowledged method for generating human regulatory DCs but even more so by the non-existence of reliable markers. Thus, we set out to find reliable markers that can be measured with simple methods to identify regulatory DCs that are applicable for future clinical studies. Human DCs were generated from peripheral blood monocytes in the presence of 1alpha,25-dihydroxyvitamin D(3) (VD3), which gave rise to a phenotype that resembles immature DCs, with the exception of high CD14 and reduced CD1a on the cell surface. These VD3-treated DCs exert a long-lasting inefficient T cell stimulation and induce T cell hyporesponsiveness with regulatory potential. Importantly, such VD3-treated DCs were readily distinguishable from untreated DCs by low levels of interleukin-23 secretion and low expression of miR-155 upon exposure to maturation stimuli. Furthermore, VD3-treated DCs showed over-expression of miR-378. All these features can be used as robust markers for quality control of VD3-treated regulatory DCs in future clinical studies.

Dendritic cells (DC) are potent antigen presenting cells capable of inducing immune responses. DC are widely used as vaccine adjuvant in experimental clinical settings. DC-based vaccines are normally generated using a standard 8day DC protocol (SDDC). In attempts to shorten the vaccine production we have developed fast DC protocol by comparing two different fast DC protocols with SDDC. DC were evaluated by FACS analysis, and the optimal profile was considered: CD14(low), CD80(high), CD83(high), CD86(high), CCR7(high), HLA class I and II(high). FACS profiles were used as the selection criteria together with yield and morphology. Two fast DC protocols fulfilled these criteria and were selected for functional analysis. Our results demonstrate that DC generated within 5days or 48h are comparable with SDDC both phenotypically and functionally. However, we found that 48h DC were more susceptible than SDDC to the IL-10 inducing stimulus of TLR ligands (R848 and LPS). Thus to determine the clinical relevance of fast DC protocols in cancer settings, small phase I trials should be conducted monitoring regulatory T cells carefully.

The clinical use of dendritic cells (DCs) to induce antigen-specific immune tolerance has been hampered by the lack of a widely acknowledged method for generating human regulatory DCs but even more so by the non-existence of reliable markers. Thus, we set out to find reliable markers that can be measured with simple methods to identify regulatory DCs that are applicable for future clinical studies. Human DCs were generated from peripheral blood monocytes in the presence of 1α,25-dihydroxyvitamin D3 (VD3), which gave rise to a phenotype that resembles immature DCs, with the exception of high CD14 and reduced CD1a on the cell surface. These VD3-treated DCs exert a long-lasting inefficient T cell stimulation and induce T cell hyporesponsiveness with regulatory potential. Importantly, such VD3-treated DCs were readily distinguishable from untreated DCs by low levels of interleukin-23 secretion and low expression of miR-155 upon exposure to maturation stimuli. Furthermore, VD3-treated DCs showed over-expression of miR-378. All these features can be used as robust markers for quality control of VD3-treated regulatory DCs in future clinical studies. [ABSTRACT FROM AUTHOR]