iDC were loaded or not with OC-L overnight, subsequently matured for 6 to 7 h using IFN and MPLA and viability of the cells was determined upon harvest (C, black circles with OC-L and black squares without OC-L). NMYC culture in cell factories in the presence of IL-4 and GM-CSF. Immature DCs were loaded with OC-L and matured using MPLA-IFN. After assessing the functionality of the OC-DC cells (IL12p70 secretion and COSTIM assay), the OC-DC vaccine was cryopreserved CL2A-SN-38 in multiple doses for single use. Finally, the stability of the formulated doses was tested and validated. We believe this GMP-compliant DC vaccine developing process will facilitate access of patients to personalized DC vaccines, and allow for multi-center clinical trials. = 0.019). As shown in Physique 1B, cell viability after dissociation was high and comparative between both dissociation methods. Again, the viability appeared to be higher for new compared to cryopreserved tumors (75.8 13.8% fresh vs. 56.8 18.2% cryopreserved for ovarian tumors dissociated with rotating mixer; 76.1 11.2% fresh vs. 62.2 10.3% cryopreserved for ovarian tumors dissociated with GentleMACS and 89.1 5.9% for fresh pancreatic tumors dissociated with GentleMACS). Our results demonstrate that this GMP-compliant tumor dissociation CL2A-SN-38 process allows for the isolation of a number of viable cells per gram of tissue sufficient to weight an average of 92.4 106 DC at a 0.5:1 OC-L: DC cell number ratio. Because of a higher efficiency of digestion using an overnight incubation at RT on a rotating mixer, we decided to use this method for OC-L clinical production. Open in a separate window Physique 1 Oxidized tumor cell lysate (OC-L) tumor dissociation and impact of OC-L loading onto dendritic cell (DC). Cryopreserved or new tumor specimens were CL2A-SN-38 dissociated using an enzymatic digestion answer and incubated either on a rotating mixer at RT (closed symbols) or using the GentleMACS (open symbols). After dissociation, the total number of viable cells per gram of tumor (A) and percentage of viability (B) were decided. iDC were loaded or not with OC-L overnight, subsequently matured for 6 to 7 h using IFN and MPLA and viability of the cells was decided upon harvest (C, black circles with OC-L and black squares without OC-L). * Mann-Whitney test, = 0.0041, n = 3 to 10. Other than the switch in the oxidative reagent, the oxidation and freeze-thaw cycle process was performed as explained by Chiang et al. Importantly, after the last freeze-thaw cycle, the viability of the CL2A-SN-38 OC-L was controlled using Trypan blue exclusion staining. Over the 28 OC-L batches produced, 0% viability was usually reached after six freeze-thaw cycles. Nonetheless, one major risk to assess was whether the traces of HOCL remaining in the OC-L could impact the DC viability after loading. This was investigated by checking the viability of iDC loaded or not with OC-L after overnight (12 to 16 h) incubation and subsequently matured for 6 to 7 h using IFN and MPLA. As shown in Physique 1C, OC-L loading did not impact DC viability at harvest. Indeed, the viability of OC-L loaded DC (76.5 6.5% viable cells) was comparable to viability of non-loaded DC (78.8 7.8% viable cells). Finally, from a quality control point of view, a colorimetric hypochlorite detection kit (Abcam) was used to detect the potential traces of HOCl in OC-L. Measurement exhibited that HOCl level in the oxidized tumor lysate is usually below the limit of detection of the assay (i.e., 0.001%), thus confirming that this method is GMP compliant. 3.2. Validation of Monocytes Isolation Using the CliniMACS Prodigy In order to perform monocytes isolation in a closed system compliant for GMP developing in a Grade D clean room, we tested and validated the positive selection of monocytes from new leukapheresis using the CliniMACS CD14 reagent and the CliniMACS Prodigy system (Miltenyi Biotec). Upon reception of the fresh leukapheresis material, the percentage of monocytes was defined by circulation cytometry based on cell size and granularity (Forward scatter (FSC)/Side scatter (SSC)). By using this percentage, the CD14 positive selection was set-up around the CliniMACS Prodigy using the LP-14 enrichment program. After CliniMACS Prodigy priming and connection of.