Inclusion Criteria:

          1. Subjects must have CD33+ AML in second or greater relapse, post-transplant relapse, or
             have demonstrated chemotherapy-refractory disease (definitions in criteria 2c) to be
             eligible to participate in this trial.

          2. Disease status at the time of enrollment:

               1. Subjects in second or greater relapse will be eligible with relapse defined as
                  >5% blasts (bone marrow) after second documented complete remission

               2. Any degree of detectable disease post-transplant relapse will be eligible (with
                  flow cytometric confirmation of CD33+ myeloid leukemia of at least 0.1%)

               3. Refractory disease is defined as persistent bone marrow involvement with >5%
                  blasts after two courses of induction chemotherapy for patients at initial
                  presentation or >5% bone marrow blasts after one course of re-induction
                  chemotherapy for patients in relapse

          3. CD33 expression must be detected on greater than 50% of the malignant cells by
             immunohistochemistry or greater than 80% by flow cytometry

          4. Age: Greater than or equal to 1 year of age (and at least 15 kg) and less than or
             equal to 35 years of age at time of enrollment. (NOTE: The first three subjects
             treated on this trial must be ≥ 16 years of age)

          5. All subjects must have an allogeneic HCT donor identified with a plan to proceed to
             HCT conditioning within 6 weeks of CD33CART cell infusion

          6. Performance status: > 50% (for subjects > 16 years of age use Karnofsky ≥ 50%;
             subjects < 16 years of age: Lansky scale ≥ 50%) Subjects who are unable to walk
             because of paralysis, but who are upright in a wheelchair will be considered
             ambulatory for the purpose of calculating the performance score;

          7. Adequate organ function as defined by:

               1. Cardiac function: left ventricular ejection fraction (LVEF) ≥ 45% or fractional
                  shortening ≥28%

               2. Pulmonary function: baseline oxygen saturation > 92% on room air at rest

               3. Hepatic function:

                    -  Total bilirubin < grade 2 bilirubin CTCAE version 5 (<3 x ULN) (except in
                       case of subjects with documented Gilbert's disease > 3 x ULN)

                    -  AST (SGOT)/ALT (SGPT) < 5 x institutional ULN (< grade 3)

               4. Renal function: Serum creatinine must be < 1.2 x institutional upper limit of
                  normal (ULN) according to age. If the serum creatinine is greater than 1.2 x ULN,
                  the patient must have a creatinine clearance (CrCl) > 70mL/min/1.73 m2 (measured
                  by 24 hour- urine specimen or radioisotope GFR).

          8. Subjects > 18 years of age must have the ability to give informed consent according to
             applicable regulatory and local institutional requirements. Legal guardian permission
             must be obtained for subjects < 18 years of age. Pediatric subjects will be included
             in age appropriate discussion in order to obtain assent; Adults with cognitive
             impairment who are unable to consent and those with Down Syndrome are also eligible
             for this protocol

          9. Enrollment in the NMDP protocol: Protocol for a Research Database for Hematopoietic
             Cell Transplantation, Other Cellular Therapies and Marrow Toxicity Injuries.

        Exclusion Criteria:

          1. Subjects with radiologically-detected CNS chloromas or CNS 3 disease (presence of ≥
             5/μL white blood cells (WBCs) in cerebral spinal fluid (CSF) and cytospin positive for
             blasts [in the absence of a traumatic lumbar puncture] and/or clinical signs of CNS
             leukemia such as a cranial nerve palsy from active disease). Subjects with adequately
             treated CNS leukemia are eligible

          2. Hyperleukocytosis (≥ 50,000 blasts/μL) or rapidly progressive disease that in the
             estimation of the investigator and sponsor would compromise ability to complete study
             therapy

          3. Pregnancy (negative serum or urine pregnancy test must be obtained at time of
             enrollment for females of childbearing potential and to be repeated 72 hours prior to
             lymphodepleting chemotherapy regimen)

          4. Breast feeding

          5. Sexually active female subjects of childbearing potential and male subjects who are of
             childbearing potential and are unwilling to practice birth control at time of
             enrollment and for four months after receiving the lymphodepletion preparative regimen

          6. Active or uncontrolled viral, bacterial or fungal infection. May be receiving ongoing
             therapy for controlled infection

          7. Treatment with any prior CAR-T therapy product

          8. Recent prior therapy:

               1. Systemic chemotherapy ≤ 2 weeks

               2. TKI ≤ 2 weeks

                    -  Exceptions: 6 weeks for gemtuzumab or other CD33-targeted antibody,
                       clofarabine or nitrosoureas;

                    -  Exception: Subjects who are on azacytidine/decitabine may be enrolled
                       provided that chemotherapy is discontinued at least 1 week prior to
                       apheresis)

                    -  There is no time restriction in regard to prior intrathecal chemotherapy for
                       initial enrollment, however, IT therapy should be performed > 72 hours prior
                       to apheresis:

                    -  Steroid therapy is not allowed, unless at or below physiologic replacement
                       doses;

                    -  Subjects receiving hydroxyurea may be enrolled provided there has been no
                       increase in dose for at least 2 weeks prior to apheresis or study enrollment
                       if an apheresis product was previously collected;

                    -  Any anti-neoplastic investigational agents or monoclonal antibody therapy
                       should not be given within 30 days prior to apheresis (i.e. start of
                       protocol therapy);

               3. For radiation therapy: Radiation therapy must have been completed at least 3
                  weeks prior to apheresis or enrollment if an apheresis product was previously
                  collected, with the exception that there is no time restriction if the volume of
                  bone marrow treated is less than 10% and also the subject has
                  measurable/evaluable disease outside the radiation port; Any CNS radiation will
                  require a 3-week washout prior to enrollment

               4. For prior stem cell transplant: Subjects with a history of more than one prior
                  stem cell transplant will not be eligible.

          9. Subjects with a history of a single allogeneic stem cell transplantation are excluded
             if:

               1. Subjects are less than 100 days post-transplant OR

               2. Subjects have evidence of ongoing active GVHD and are taking immunosuppressive
                  agents (>0.5 mg/kg/methylprednisolone equivalents or other immunosuppression for
                  GVHD treatment) OR

               3. Subjects have received DLI within 30 days prior to enrollment OR

               4. Subjects are on active immunosuppression for GVHD prophylaxis (must be off for 30
                  days prior to enrollment)

         10. HIV/HBV/HCV Infection:

               1. Seropositive for HIV 1 or 2 (Subjects with HIV are at increased risk of lethal
                  infections when treated with marrow-suppressive therapy. Appropriate studies will
                  be undertaken in subjects receiving combination antiretroviral therapy in the
                  future should study results indicate effectiveness)

               2. Seropositive for Hepatitis C or positive for Hepatitis B surface antigen (HbsAG)

         11. Uncontrolled, symptomatic, intercurrent illness including but not limited to
             infection, congestive heart failure, unstable angina pectoris, cardiac arrhythmia,
             psychiatric illness, or social situations that would limit compliance with study
             requirements or in the opinion of the site PI would pose an unacceptable risk to the
             subject

         12. Active second malignancy will not be eligible with the following exceptions:

               1. Treatment-related or secondary CD33+ myeloid malignancy which may potentially
                  benefit from CD33CART (which may be considered for enrollment),

               2. Carcinoma in situ of the cervix (which may be considered for enrollment),

               3. Subject is in remission from a prior second malignancy (which may be considered
                  for enrollment).

         13. History of severe, immediate hypersensitivity reaction attributed to compounds of
             similar chemical or biologic composition to any agents used in study or in the
             manufacturing of the cells (i.e. gentamicin).