Mesenchymal Stem Cells Transplantation to Patients With Relapsed/Refractory Aplastic Anemia.

Inclusion Criteria:

• Patients must fulfill definition of aplastic anaemia: There must be at least two of the following: haemoglobin < 100g/L; platelet count < 50 x 109/L; neutrophil count < 1.5 x 109/L, and ahypocellular bone marrow; SAA as defined by a hypocellular bone marrow of <25% cellularity and two of the following: neutrophil count < 0.5 x 109/L platelets < 20 x 109/L reticulocytes < 20 x 109/L nSAA asdefined by a hypocellular bone marrow and cytopenia in at least two cell lines andneutrophil count > 0.5 x 109/L, and red cell and/or platelet transfusion dependence.

• Patients belong to acquired aplastic anaemia.

• Patients with a history SAA must have had an incomplete response at least 3 monthsfollowing treatment with ATG/CsA, or they must have relapsed following an initialresponse to treatment, and they do not have a HLA-matched donor for bone marrowtransplantation. Patients with a history nSAA must have red cell and/or platelettransfusion dependence.

• Peripheral blood counts at the time of enrollment must include at least one of thefollowing: haemoglobin < 90 g/L or red blood cell (RBC) transfusion dependence, PMN < 1 x 109/L, or platelet count < 50 x 109/L.

• Patients must have organ function as defined below: total bilirubin within normal institutional limits (NV: 0.0-20.5 umol/L)AST(SGOT)/ALT(SGPT) < 2.5 × institutional upper limit of normal AST (NV: 0-35 U/L); ALT (NV: 0-40 U/L) Creatinine within normal institutional limits (NV: 53-106 umol/L) orCreatinine clearance > 1.25 ml/s for patients with creatinine levels above institutionalnormal.

• Age minimum 16 years old with no upper age limit.

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

Exclusion Criteria:

• Patients may not be receiving any other investigational agents within 4 weeks of studyentry.

• History of allergic reactions attributed to compounds of similar biologic compositionto mesenchymal stem cells.

• Current diagnosis of Fanconi's anemia, Dyskeratosis Congenita (DC) or other hereditaryforms of AA.

• Psychiatric, addictive or any other disorder that compromises ability to give a trulyinformed consent.

• Age < 16 years old.

• ECOG performance status > 2.

• Malignancy within the last 5 years.

• Uncontrolled intercurrent illness including, but not limited to, ongoing or activeinfection (defined as invasive fungal infection and progressive CMV viremia),symptomatic congestive heart failure (NYH class III and IV), unstable angina pectoris,or cardiac arrhythmia.

• Pregnant or breastfeeding women.

• HIV-positive patients.