• Patients with AML who have undergone AML cell harvest and cryopreservation as per protocol 16-593 or companion protocol 18-232.

• Patients must have had a minimum of 5x107 cells cryopreserved.

• Patients must be day 25-45 following allogeneic transplantation from either:

‣ Group A: HLA 8/8 or 7/8 matched related donor or HLA 8/8 matched unrelated donor, as determined by antigen or allele level typing at HLA A,B,C, and HLA DRB1.

∙ OR

• Group B: Haplo-identical donor

‣ Patients must be ≥ 18 years old

⁃ ECOG performance status ≤2 (Appendix A)

⁃ Participants must have normal organ and marrow function as defined below:

• Total bilirubin ≤ 2.0 mg/dL (unless patient has Gilbert's disease)

• AST(SGOT)/ALT(SGPT) ≤ 3 × institutional upper limit of normal

• Creatinine ≤ 2.0 mg/dl

• Absolute neutrophil count \> 1000

• Platelet count \> 50,000

‣ The effects of DC/AML fusion cells on the developing human fetus are unknown. For this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.

⁃ No evidence of ongoing grade 2 or higher aGVHD

⁃ Must be on prednisone \<20mg or other steroid equivalent

⁃ Donor chimerism of bone marrow \>60%

⁃ Resolution of all transplant related grade III-IV toxicity as per CTC criteria 4.0

⁃ Complete remission defined by absence of circulating blasts and less than 5% blasts in the bone marrow

⁃ Ability to understand and the willingness to sign a written informed consent document.

∙ Eligibility Prior to Initiating Vaccination (Groups A and B)

• Assessments to be done between Day 45-75 post-transplant.

• At least 2 doses of fusion vaccine were produced

• No ongoing grade II-IV acute GVHD

• Prednisone requirement of \< 20mg a day or steroid equivalent

• Participants must have normal organ and marrow function as defined below:

‣ Total bilirubin ≤ 2.0 mg/dL (unless patient has Gilbert's disease)

⁃ AST(SGOT)/ALT(SGPT) ≤ 3 × institutional upper limit of normal

⁃ Creatinine ≤ 2.0 mg/dl

⁃ Absolute neutrophil count \> 1000

⁃ Platelet count \> 50,000

• No uncontrolled acute infection

• No CTCAE grade ≥ 3 non-hematologic toxicity

• No serious intercurrent illness such as active acute infection, or significant cardiac disease characterized by clinically significant arrhythmia, active ischemic coronary disease or symptomatic congestive heart failure.

• Participants must be in a complete remission

∙ Pre-Treatment Criteria Prior to Decitabine (Group A Cohort 2)

• Assessments to be done within 3 days prior to initiation of therapy.

• Participants must have normal organ and marrow function as defined below:

• Total bilirubin ≤ 2.0 mg/dL (unless patient has Gilbert's disease)

‣ AST(SGOT)/ALT(SGPT) ≤ 3 × institutional upper limit of normal

⁃ Creatinine ≤ 2.0 mg/dl

⁃ Absolute neutrophil count \> 1000

⁃ Platelet count \> 50,000