Ith concentrate around the evaluation of their impact on CLL immune escape. Altogether, this study will give insight into the certain immune and stromal cells involved in CLL improvement, with emphasis on their involvement in tumour-derived modest Ev-mediated tumour immune escape. Funding: This project is funded by the Fonds National de la Recherche (FNR) INTER/DFG/16/11509946/EVRNA/Moussay. Sandrine Pierson and J e Paggetti are supported by the FNR INTER/DFG/16/11509946/EV-RNA/ Moussay. Ernesto Gargiulo is supported by the grant FNR Luxembourg PRIDE15/10675146/CANBIO.PT06.Interaction via exosome miRNAs among myelodysplatic cell and normal Treg Tatsuki Shibuta, Yukichi Takada and Tsukuru Umemura International University of Health and Welfare, Okawa City, Japanregulatory T cells (Treg) that had been sorted from Integrin Proteins medchemexpress standard peripheral blood. The exosomes had been detected in cytosol of Treg by fluorescent microscopy. Microarray analysis of miRNAs in Treg intaking MDS-exosomes showed that significant increases of 9 miRNAs in MDS-exosomes. The conditioned ICAM-2/CD102 Proteins Source medium of MDSexosomes treated Treg culture reduced the population of activated CD4 cells (CD38 positive cells was 39 ; control 68). Summary/Conclusion: Our information recommended that exosomes from MDS cells impacted the function of regulatory T cells by way of miRNA transfer. MDS exosomes may perhaps impact on immune cells to prevent the exclusion from cancer-immune system, and may be a target for the new therapies or diagnostic solutions. Funding: This function was supported in aspect by a grant in the Japan Society for the Promotion of Science (JSPS KAKENHI Grant Number: JP17K09020 and 17H07059).PT06.Mechanism of antitumor immunity activation by `artificial neoantigen’-presenting exosomes Yoshiyuki Koyamaa, Tomoko Itoa, Masazumi Eriguchia, Aya Hasegawab, Wakana Ouchic, Toshio Inabab and Kikuya SugiurabaIntroduction: Myelodysplastic Syndrome (MDS) is really a clonalhematopoietic illness and develops leukaemia in some instances. Thus, MDS is a malignant hematopoietic disease and its prevalence ratio is growing in Japan. Hematopoietic microenvironment such as bone marrow niche is a important element for maintaining leukaemic stem cells. To know mechanisms of interactions involving leukaemic stem cells and microenvironment is important for the remedy of hematopoietic malignancies. In this study, to create the new therapies and diagnostic solutions for MDS, we focused on the effect of exosomes released from MDS cells on peripheral T lymphocytes. Methods: MDS cell line (MDS-L) was kindly offered by Kasawaki Healthcare University and regular peripheral blood mononuclear cells have been obtained from healthy volunteer donors. Exosomes from MDS cells had been purified by utilizing miRCURY Exosome Cell/Urine/CSF Kit and labelled by PKH67. Extracted miRNAs had been analysed by microarray process (Genopal, Mitsubishi Chemical, Japan). Cell surface antigens have been analysed by FACS Aria II and fluorescence conjugated antibodies. Results: miRNA-microarray evaluation showed that nine miRNAs had been abundant in exosomes from MDS cells and have been not detected in MDS cells. Exosomes labelled with PKH67 dye were added to liquid culture ofJapan Anti-tuberculosis Association, Shin-Yamanote Hospital, Tokyo, Japan; Osaka Prefecture University, Osaka, Japan; cOsaka Prefecture University, Tokyo, JapanbIntroduction: Tumour-derived exosomes are identified to have very same antigens as the parent tumour cells, and had been anticipated as cancer vaccines. On the other hand, therapy with those exosomes usually failed to elicit.