Functional characteristics and clinical effectiveness of platelet concentrates treated with riboflavin and ultraviolet light in plasma and in platelet additive solution.

BACKGROUND AND OBJECTIVES: Pathogen reduction technologies may affect platelet quality during storage. We studied functional characteristics and clinical effectiveness of platelet concentrates (PCs) treated with Mirasol in plasma and in platelet-additive solution SSP+. MATERIALS AND METHODS: Mirasol-treated, gamma-irradiated and untreated apheresis PCs were examined on days 0, 1, 3 and 5 of storage. Phosphatidylserine, P-selectin and active glycoprotein IIb/IIIa were analysed using flow cytometry before and after platelet stimulation. Platelet count increments, the numbers of inefficient transfusions and post-transfusion reactions were analysed to estimate clinical effectiveness. RESULTS: A significant increase in all platelet activation markers occurred during storage in all PC groups. Activation markers in Mirasol-treated samples were already significantly higher compared with the control ones on the day of harvesting, and continued to grow during the storage. Mirasol treatment increased the number of platelets with a mitochondrial membrane potential loss. On the 3rd day of storage, 50% of Mirasol-treated platelets did not respond to activation; on the 5th day, none did. This agreed well with a decrease (approximately twofold) in the effectiveness of Mirasol-treated PC transfusions. Transfusions of PCs stored in SSP+ were accompanied by fewer inefficient transfusions and post-transfusion reactions than of PCs stored in plasma. CONCLUSION: Treatment with Mirasol decreased platelet function, particularly profoundly on the 5th day of storage, and led to a decrease in the effectiveness of transfusions. SSP+ did not affect laboratory parameters significantly compared with plasma, but decreased the percentage of transfusion complications.

Efficacy of plerixafor in children with malignant tumors failing to mobilize a sufficient number of hematopoietic progenitors with G-CSF.

Mobilization of suitable amounts of PBSCs with granulocyte-CSF (G-CSF) can be difficult in children. We report the results of using plerixafor in pediatric patients who failed to mobilize progenitors with G-CSF-based regimens. Thirty-three patients, median age 9 years (range 1-18 years) and median weight 29 kg (range 10-85 kg) were enrolled into the study. After 4 days of G-CSF stimulation, the median CD34+ cell count in peripheral blood was 10.4 per µL (range 0.27-23.0 per µL). Plerixafor was administered subcutaneously (0.24 µg/kg in 30 patients and 0.3 µg/kg in 3 patients) 11-12 h before apheresis. At the time of apheresis, CD34+ cell counts increased to a median of 44.1 per µL (range 8.4-357.0 per µL), a median 4.4-fold increase. Two patients (6%) failed to mobilize. Thirty-one patients underwent apheresis and in 27 >2 × 10(6) CD34+ cells per kg of body weight were collected after one procedure. In total, 31 of 33 patients mobilized successfully and the median number of cryopreserved CD34+ cells was 5.6 × 10(6) /kg body weight (2.7 × 10(6)-27.4 × 10(6)). Twenty-four patients underwent transplantation. Engraftment was achieved in all but one patient, who died on day +9 after hematopoietic stem cell transplantation. The median time of neutrophil and platelet recovery was day +12 and +16, respectively. Our study confirms that plerixafor has impressive efficacy and very modest toxicity in children.

[Results of hematopoietic cell transplantation in the first complete remission in children with acute myeloid leukemia from an intermediate risk group].

AIM: To analyze the results of allogeneic and autologous hemopoietic cell transplantations (allo- and auto-HCT) in children with acute myeloid leukemia (AML) from an intermediate risk group, most of which were performed using lower-intensity conditioning modes. SUBJECTS AND METHODS. The study enrolled 36 children from an intermediate risk group, who had undergone auto-HCT (n = 22) or allo-HCT (n = 14) in December 1994 to December 2008. The patients' age was 0.7 to 16.6 years (median 12.8 years). Chemotherapeutic conditioning regimens were applied to all the patients. Melphalan was a basic myeloablative agent in 83.3% of cases. RESULTS: With a median follow-up of 4.6 years (1.1-13.8 years), three-year relapse-free survival (RFS) was 80.4%; overall survival (OS) was 65.6%. Recurrences were documented only in 6 (16.6%) patients from the auto-HCT. Transplantation-associated mortality (TAM) was 13.8% (five patients died). After allo-HCT versus auto-HCT, RFS, OS, and TAM were 100 and 68.7% (p = 0.03), 93.2 and 55.5% (p = 0.02), and 7.1 and 18.2%, respectively. Acute and chronic graft-versus-host reactions developed in 57.1 and 23.1%, respectively. CONCLUSION: Transplantation of allogeneic hemopoietic cells from a compatible related donor in the intermediate risk group children with AML, by using melphalan-based conditioning regimen, demonstrates a high survival rate with the minimum toxicity.

[Transplantation of the bone marrow from a HLA-compatible unrelated donor after immunoablative conditioning in children with acquired aplastic anemia unresponsive to combined immunosuppressive therapy: preliminary results].

AIM: To analyze the efficiency of transplantation of the bone marrow from a HLA-compatible unrelated donor and continued immunosuppressive therapy (IST) in children with aplastic anemia (AA) unresponsive to 2 courses of IST. SUBJECTS AND METHODS: The study enrolled 14 children aged 2-16 years (median 9 years). A control group comprised 26 patients in whom IST was continued. The median interval between the diagnosis of AA and transplantation was 26 months (9-156 months). The conditioning regimen consisted of thoracoabdominal irradiation in a dose of 2 Gy, fludarabin (Flu) 100-150 mg/m2, cyclophosphamide (Cy) 100-200 mg/kg, antithymocyte globulin (ATG) in 11 patients and Flu, Cy, and ATG in 3. A graft-versus-host reaction was prevented with mycophenolate mefetil in all the patients, tacrolimus in 11, and cyclosporin A in 3. Donors were compatible for high-resolution typing of 10/10 and 9/10 alleles in 8 and 6 patients, respectively; the source of a transplant was bone marrow in 13 patients and granulocyte colony-stimulating factor-mobilized peripheral blood precursors in one case. RESULTS: Thirteen patients achieved primary engraftment after single transplantation; one patient did after repeat transplantation. Grades I to II graft-versus-host reaction (GVHR) developed in 9 patients; postengraftment life-threatening infections in 3, extensive chronic GVHR in 2, circumscribed GVHR in 7. All fourteen hemopoietic cell transplant recipients followed for a median 17.5 months (range 1-71 months) were survivors. CONCLUSION: The likelihood of good survival after unrelated transplantations in AA is much higher than that after continued IST: 100% versus 15 +/- 11%.

[Clinico-laboratory variants of the course and results of therapy of hepatitis-associated aplastic anemias in children].

AIM: To study clinical and laboratory characteristics of hepatitides and evaluate efficacy of immunosuppressive therapy and transplantation of the bone marrow in hepatitis-associated aplastic anemia (HAAA). MATERIAL AND METHODS: A retrospective analysis of case histories of children with HAAA was made. For all the patients standard tests for detection of aquired aplastic anemia and hepatitis were conducted. Transplantation of hemopoietic stem cells (THSC) from HLA-identical donors was made in 4 patients, 25 patients were treated with combined immunosuppressive therapy (antithymocytic globulin--ATG plus cyclosporin A -CsA), one patients received monotherapy with CsA, two--prednisolone and a short course of CsA, one child was untreated. RESULTS: Of 260 children admitted to hospital from April 1989 to July 2005 for aquired aplastic anemia, 33 (12.7%) met diagnostic criteria of HAAA. Boys to girls ratio was 267. Hepatitides were severe: median of alaninaminotransferase concentration was 1215 IU/l, aspartataminotransferase--789 IU/l, bilirubin--152.5 mcmol/l. Median of the interval from hepatitis symptoms to documentation of pancytopenia was 66 days (0-204 days). All four patients after THSC are alive for 30-72 months. Probability of complete remission after the first course of ATG+CsA is 0.72 +/- 0.09, probability of survival 0.81 +/- 0.07, median of the interval to transfusion independence--50 days. CONCLUSION: HAAA prognosis is good only in administration of up-to-date therapy. After seronegative hepatitis it is necessary to control hemogram parameters and in the presence of minimal cytopenia patients should be directed to hematological hospital.

Fludarabine, low-dose busulfan and antithymocyte globulin as conditioning for Fanconi anemia patients receiving bone marrow transplantation from HLA-compatible related donors.

Allogeneic hematopoietic stem cell transplantation (SCT) from unaffected donors remains the only modality for the correction of hematological abnormalities in Fanconi anemia (FA) patients. We performed four HLA-matched related donor SCT using a novel irradiation and cyclophosphamide-free conditioning regimen. The protocol included fludarabine 150 mg/m(2), busulfan 4 mg/kg, and antithymocyte globulin 90 mg/kg. Graft-versus-host disease (GVHD) prophylaxis was cyclosporin A, MTX, and daclizumab. The engraftment and occurrence of full stable donor hemopoiesis was rapid in all cases with minimal short-term toxic complications. There were no infections or febrile episodes during the inpatient phase. Three patients developed acute GVHD grade I-II involving gut and skin and one patient progressed to extensive chronic GVHD. The preparative conditioning regimen is safe and associated with low organ toxicity and effective immunosupression for the stable engraftment in FA patients undergoing SCT with matched related donors.

Successful treatment of pure red cell aplasia with a single dose of rituximab in a child after major ABO incompatible peripheral blood allogeneic stem cell transplantation for acquired aplastic anemia.

Pure red cell aplasia (PRCA) is a well-known although infrequent hematologic complication after allogeneic bone marrow transplantation. PRCA occurs in cases of major ABO-mismatch between donor and recipient and is believed to be due to inhibition of donor erythroid progenitors by residual host isohemagglutinins. We report a 10-year-old boy with post-hepatitis aplastic anemia (AA) who developed PRCA after HLA-matched familial peripheral blood stem cell transplantation (SCT) following conditioning with Cph 200 mg/kg + ATG 90 mg/kg. Granulocyte engraftment occurred on day +18, platelet engrafted on day +40, while reticulocytopenia at 0% persisted until day +118, and erythroid precursors were totally absent from bone marrow. After a single dose of rituximab 200 mg/m(2)administered on day +118 PRCA resolved and on day +132 the reticulocytes rose to 5.7%. On day +139 the Hb reached 137 g/l and the erythroid lineage in BM increased to 21%. We conclude that due to the rapid recovery from PRCA and lack of side effects, rituximab should be tried as first-line treatment of PRCA after allo-SCT.

A successful cord blood transplant in a child with second accelerated phase chronic myeloid leukemia following lymphoid blast crisis.

We describe a 5-year-old girl with Ph(+) CML who received a cord blood transplant in a second accelerated phase after a very early lymphoid blast crisis. She was induced into CR by ALL-directed chemotherapy and then maintained with IFN-alpha2b together with weekly rotational chemotherapy. Nineteen months after diagnosis, her mother gave birth to an HLA-compatible sibling, whose cord blood was cryopreserved. The patient's second acceleration occurred 22 months after the CML diagnosis. The subsequent conditioning regimen included busulfan 16 mg/kg, Ara-C 12 g/m2 and melphalan 140 mg/m2. In order to prevent GVHD, CsA alone was administered, 3 mg/kg i.v. per day for a total of 40 days. The total number of nucleated cells infused was 0.8 x 108/kg, with CD34+ cells 1.8 x 106/kg and CFU-GM 1 x 104/kg. Engraftment occurred on day +35. Respiratory distress, severe VOD and grade II acute gastrointestinal GVHD complicated the post-transplant period. No chronic GVHD occurred. The girl is alive 23 months after transplantation with complete donor chimerism; both Ph chromosome and bcr/abl RNA are negative. Bone Marrow Transplantation (2000) 25, 213-215.

[Comparative characterization of oxidative stress in some hereditary diseases differing in predisposition of neoplasms and early aging]. / Sravnitel'naia kharakteristika oksidativnogo stressa pri nekotorykh nasledstvennykh zabolevaniiakh, otlichaiushchikhsia predraspolozhennost'iu k zlokachestvennym novoobrazovaniiam i rannemu stareniiu.

Two groups of hereditary diseases are considered. One group is characterized by chromosomal instability (Fanconi's anemia, ataxiatelenagioectasia, xeroderma pigmentosum). The other group includes diseases with marked genotypic changes (Down's disease, cystic fibrosis). All these diseases predispose to malignant neoplasms and premature ageing, which is due to different manifestations of oxidative stress. The paper gives in greatest detail the mechanism responsible for Fanconi's anemia which has been much studied by the authors. Chromosomal instability in this disease is associated with regeneration defect in DNA impaired by oxygen radicals.