5- 6). We believe these advances will sig nificantly enhance the potential clinical impact of our proposed therapeutic approach. Admittedly, as more potent vaccination platforms are advanced, the risks of inducing intolerable autoimmunity will also likely increase, and thus careful evaluation of the safety of these potent vaccination platforms will be necessary. Our proposed phase I study will establish the safety of DC + xALT therapy using amplified total tumor RNA pulsed DC vaccines to expand tumor -specific lymphocytes in vitro for adoptive tra nsfer and maintenance in vivo with DC vaccination. 6.3 Rationale for Current Study Adoptive cellular therapy after lymphodepletive regimens has emerged as a potent and effective means of inducing durable remissions of advanced stage refractory melanoma and therefore holds significant promise in the treatment of other solid tumors. Recurrent MB/PNETs are the most common pediatric brain tumors and brain cancer is currently the leading cause of cancer deaths in children. The use of HDC + PBSCT and NMA chemother apy as standard therapy in patients with reMB/PNETs provides an ideal opportunity to administer adoptive cellular therapy during the hematopoietic recovery phase from HDC and NMA chemotherapy . We have developed the use of total tumor RNA loaded DCs as an effective platform for induction of tumor -specific lymphocytes and will use TTRNA -pulsed DCs to expand lymphocytes specific for reMB/PNETs from children undergoing secondary resection and HDC + PBSCT (Group A) or NMA salvage chemotherapy (Group B) . In order to maintain T cell expansion and function al administration concurrent and monthly vaccinations with TTRNA -pulsed autologous DCs will be administered. Re-MATC H Protocol Page 40 of 106 Version: 20180628 6.4 Re-MATCH Phase I Study 21 subjects were enrolled on the protocol using a screening consent for tumor collection. Eleven of these subjects were removed from the study (ineligible histology, tumor progression, inability to obtain sufficient PBMCs for DC/xALT generation) prior to immunotherapy. Ten subjects were treated with DC+ALT therapy and nine were evaluable for the maximal tolerated dose (MTD) and dose -limiting toxicities (DLTs). One patient’s T cells did not grow and was treated with DC vaccination only and thus not evaluable for phase I safety endpoints. Therefore, ten were treated with DCs/xALT with nine of these patients evaluable for DLTs and MTD. For Group A, we treated a single subject that reached the safety endpoint at dose cohort #1 (3x10 6 T cells/Kg). For Group B, we treated three subjects that reached the saf ety endpoint at dose cohort #1, and 5 subjects at dose cohort #2 ( 3x107 T cells/Kg ). A maximal achievable dose of T cells was obtained at 3x107 T cells/Kg. Of the nine patients who were evaluable for DLTs and MTD (Group A, N=1; Group B, N=8), no DLTs were associated with adoptive cellular therapy as defined at two weeks after the third dendritic cell (DC) vaccination. The phase I study was closed with a defined safe dose of 3x10 7 T cells/Kg i.v. and 1x107 DCs i.d.