Inclusion Criteria prior to enrollment:

   - 1. Age > 1 months (with minimum weight of 10 Kg) and < 45 years.

   - 2. Patients deemed eligible for allogeneic HSCT under the originating study, NCT
   04249830

   - 3. Patients with life-threatening hematological malignancies for which HSCT has been
   recommended:

      1. High-risk ALL in 1st CR, ALL in 2nd or subsequent CR;

      2. High-risk AML in 1st CR, AML in 2nd or subsequent CR;

      3. Myelodysplastic syndrome;

      4. JMML (Juvenile myelomonocytic leukemia);

      5. Non-Hodgkin lymphomas in 2nd or subsequent CR;

      6. Other hematologic malignancies eligible for stem cell transplantation per
      institutional standard.

   - 4. All subjects ≥ 18 years of age must be able to give informed consent, or adults
   lacking capacity to consent must have a LAR available to provide consent. For subjects
   <18 years old their LAR (i.e. parent or guardian) must give informed consent.
   Pediatric subjects will be included in age appropriate discussion and verbal assent
   will be obtained for those > 7 years of age, when appropriate.

Inclusion criteria prior to T-allo10 infusion:

   1. Patient already received αβdepleted-HSCT and has myeloid engraftment.

   2. Absence of active grade II aGvHD requiring >0.5 mg/Kg of steroids or any diagnosis of
   grade III/IVaGvHD.

Exclusion Criteria prior to MNC collection for Tallo-10 manufacturing.:

   1. Not eligible to receive HSCT on NCT04249830

   2. Received another investigational agent within 30 days of enrollment.

   3. Pregnancy (positive serum or urine beta-HCG) within 7 days of MNC donation.

   4. Patient or donor is not willing or able to undergo an additional non-mobilized
   apheresis for collection of MNC prior to donation of cells for participation in
   NCT04249830.