RecruitingBiological interventionDual-Target GD2/B7-H3 CAR-NK Cells for Pediatric Relapsed or Refractory NeuroblastomaThis illustrative Phase 1/Phase 2 study tests allogeneic dual-target GD2/B7-H3 (CD276) CAR-NK cells in children and young adults with relapsed or refractory neuroblastoma. After lymphodepletion, participants receive IV CAR-NK cells;Part A defines the RP2D and Part B estimates preliminary activity