Inclusion Criteria:

          -  Refractory AML without CR after induction therapy (primary induction failure);
             relapsed AML after obtaining a CR; progressive AML after non-intensive therapy (e.g.,
             HMA + venetoclax or targeted therapy); Intermediate risk to very-high-risk MDS by
             IPSS-R that is relapsed or refractory after prior therapy with an HMA-containing
             regimen

          -  At least 18 years of age.

          -  Available allogeneic donor that meets the following criteria:

               -  Able and willing to undergo multiple rounds of leukapheresis

               -  At least 18 years of age

               -  In general good health, and medically able to tolerate leukapheresis required for
                  harvesting the NK cells for this study.

               -  Negative for hepatitis, HTLV, and HIV on donor viral screen

               -  Not pregnant

               -  Voluntary written consent to participate in this study

               -  All HLA-match/mismatch statuses will be included, with preference for unmatched
                  donors all else being equal

          -  Patients with known CNS involvement with AML are eligible provided that they have been
             treated and CSF is clear for at least 2 weeks prior to enrollment into the study. CNS
             therapy (chemotherapy or radiation) should continue as medically indicated during the
             study treatment.

          -  Karnofsky/Lansky performance status > 50 %

          -  Adequate organ function as defined below:

               -  Total bilirubin < 2 mg/dL

               -  AST(SGOT)/ALT(SGPT) < 3.0 x ULN

               -  Creatinine within normal institutional limits OR creatinine clearance ≥ 40 mL/min
                  by Cockcroft-Gault Formula

               -  Oxygen saturation ≥90% on room air

               -  Ejection fraction ≥35%

          -  Able to be off corticosteroids and any other immune suppressive medications beginning
             on Day -3 and continuing until 30 days after the last infusion of the WU-NK-101.
             However, use of low-level corticosteroids is permitted if deemed medically necessary.
             Low-level corticosteroid use is defined as 10mg or less of prednisone (or equivalent
             for other steroids) per day.

          -  Women of childbearing potential must have a negative pregnancy test within 28 days
             prior to study registration. Female and male patients (along with their female
             partners) must agree to use two forms of acceptable contraception, including one
             barrier method, during participation in the study and until 30 days after the last
             WU-NK-101 infusion.

          -  Ability to understand and willingness to sign an IRB approved written informed consent
             document

        Exclusion Criteria:

          -  Relapsed after allogeneic transplantation.

          -  Circulating blast count >30,000/µL by morphology or flow cytometry (cytoreductive
             therapies including leukapheresis or hydroxyurea are allowed).

          -  Uncontrolled bacterial or viral infections, or known HIV, Hepatitis B or C infection.

          -  Uncontrolled angina, severe uncontrolled ventricular arrhythmias, or EKG suggestive of
             acute ischemia or active conduction system abnormalities.

          -  New progressive pulmonary infiltrates on screening chest x-ray or chest CT scan that
             have not been evaluated with bronchoscopy. Infiltrates attributed to infection must be
             stable/ improving after 1 week of appropriate therapy (4 weeks for presumed or proven
             fungal infections).

          -  Known hypersensitivity to one or more of the study agents.

          -  Received any investigational drugs within the 14 days prior to the first dose of
             fludarabine.

          -  Pregnant and/or breastfeeding.

          -  Any condition that, in the opinion of the investigator, would prevent the participant
             from consenting to or participating in the study