Patient description: The patient is a 16-year-old girl recently diagnosed with myasthenia gravis, class IIa. She complains of diplopia and weakness affecting in her upper extremities. She had a positive anti-AChR antibody test, and her single fiber electromyography (SFEMG) was positive. She is on acetylcholinesterase inhibitor treatment combined with immunosuppressants. But she still has some symptoms. She does not smoke or use illicit drugs. She is not sexually active, and her menses are regular. Her physical exam and lab studies are not remarkable for any other abnormalities. BP: 110/75 Hgb: 11 g/dl WBC: 8000 /mm3 Plt: 300000 /ml Creatinine: 0.5 mg/dl BUN: 10 mg/dl Beta hcg: negative for pregnancy

Clinical trial eligibility criteria: eligible ages (years): 3.0-21.0,  Diffuse Intrinsic Pontine Glioma Glioma Diffuse Midline Glioma, H3 K27M-Mutant Stratum A: • Newly diagnosed children (3-21 years old) with DIPG who are positive for the H3.3K27M mutation (positive testing in CLIA laboratory) that underwent standard radiation therapy Stratum B Newly diagnosed children (3-21 years old) with diagnosis of glioma other than DIPG who are positive for the H3.3K27M mutation (positive testing in CLIA laboratory) including spinal cord gliomas that underwent standard radiation therapy Stratum C • Newly diagnosed children 3-21 years of age with diagnosis of DIPG or midline glioma other than DIPG (excluding spinal cord gliomas) who are positive for the H3.3K27M mutation (positive testing from a CLIA or equivalent laboratory required), that underwent standard radiation therapy. The following apply to strata A, B and C The patient must test positive for HLA-A*02:01 (positive testing from a CLIA or equivalent laboratory required; only the HLA A*02:01 subtype is eligible; other subtypes are excluded) The patient must be either off systemic steroids or be on stable dose of dexamethasone (max 0.1 mg/kg/day; maximum 4mg/day) at time of enrollment Patients must not have received any prior chemotherapy, immunotherapy or bone marrow transplant for the treatment of their tumor. Prior use of temozolomide during radiation at maximum of the standard pediatric dosing (defined as 90 mg/m^2/dose continuously during radiation therapy for 42 days) or dexamethasone is allowed Patients must have undergone radiation therapy and surgery as part of their standard of care. o Stratum A: Radiation therapy must have started within 4 weeks of diagnosis by imaging or surgery, whichever is later. o Stratum B: For subjects undergoing surgery for more extensive resection, radiation therapy should be started within 4-6 weeks from surgery. o Stratum C: Radiation therapy must have started within 4 weeks of diagnosis by imaging or surgery, whichever is later. For subjects undergoing surgery for more extensive resection, radiation therapy should be started within 4-6 weeks from surgery H3.3K27 mutation must have been confirmed in the tumor tissue in a CLIA or equivalent approved laboratory Karnofsky ≥ 50 for patients ≥ 16 years of age, and Lansky ≥ 50 for patients < 16 years of age (See Appendix A). Patients who are unable to walk because of paralysis, but who are up in a wheelchair, will be considered ambulatory for the purpose of assessing the performance score  Investigational Drugs Patients who are currently receiving another investigational drug are not eligible Prior treatment with another investigational drug Anti-cancer Agents Patients who are currently receiving other anti-cancer agents are not eligible Prior treatment with other anti-cancer agents Patients who have received a live / attenuated vaccine within 30 days of first treatment Patients with a known disorder that affects their immune system, such as HIV or Hepatitis B or C, or an auto-immune disorder requiring systemic cytotoxic or immunosuppressive therapy are not eligible. Note: Patients that are currently using inhaled, intranasal, ocular, topical or other non-oral or non-IV steroids are not necessarily excluded from the study but need to be discussed with the study chair Patients with a ≥ Grade 2 hypothyroidism due to history of autoimmunity are not eligible. (Note: Hypothyroidism due to previous irradiation or thyroidectomy will not impact eligibility) Patients who have received prior solid organ or bone marrow transplantation are not eligible