Illuminate: A Clinical Study Evaluating CAR T Immune Cell Therapy (BCB-276) for Patients With Diffuse Intrinsic Pontine Glioma (DIPG).

Inclusion Criteria:

* Participants must be aged 1 and ≤ 26 years and weigh ≥10kg.
* Diagnosis of Diffuse Intrinsic Pontine Glioma (DIPG) based on imaging, with or without biopsy confirmation consistent with high-grade glioma or diffuse midline glioma
* Able to tolerate leukapheresis and other study procedures in the opinion of the Investigator.
* Central Nervous System (CNS) reservoir catheter present prior to first dose of study drug.
* Participant must have completed standard radiation therapy within 6 weeks of enrollment for participation.
* Performance Status of ≥ 60; mild to moderate restriction or better. Lansky (under 16 years of age) or Karnofsky (16 years of age or older).
* Adequate organ function and overall clinical status to participate, including stable or improving neurologic symptoms.
* Participants of childbearing/fathering potential must agree to use highly effective contraception from the time of enrollment through 12 months following the last T cell infusion.
* Participants with ventriculoperitoneal (VP) shunts need to have a programable system and be able to tolerate temporary adjustment of the shunt required for study treatment.
* Participant must meet all other health and safety criteria defined in the study protocol.
* Participant and/or authorized legal representative willing to provide consent/assent for study participation, including participation in the 15-year long term follow up period.

Exclusion Criteria:

An individual who meets any of the following criteria will be excluded from participation in this study:

* Previous tumor-directed therapy or treatment-directed clinical study other than standard radiation with or without temozolamide.
* Evidence of metastatic disease.
* Requirement of high or increasing doses of corticosteroids prior to participation.
* Severe swallowing difficulties or other significant clinical conditions that may interfere with participation.
* Presence of an active malignancy other than DIPG.
* Active or uncontrolled human immunodeficiency virus (HIV), hepatitis B, or hepatitis C infection based on protocol-required laboratory testing.
* Pregnant or breastfeeding.
* Presence of any condition that, in the Investigator's opinion, would prohibit the participant from undergoing treatment under this protocol.