DIPG-23. PHASE I STUDY OF ADOPTIVE CELLULAR THERAPY (X-ALT) PLUS TOTAL TUMOR RNA-DENDRITIC CELL VACCINE (TTRNA-DC) + HEMATOPOIETIC STEM CELLS (HSC) DURING RECOVERY FROM IRRADIATION(RT) WITH (GROUP A) OR WITHOUT (GROUP B) DOSE-INTENSIFIED TEMOZOLOMIDE (DI-TMZ) IN PATIENT (PTS) WITH NEWLY DIAGNOSED DIFFUSE BRAIN STEM GLIOMAS (DIPG) (BRAVO TRIAL)