Infrapatellar Fat Pad: An Alternative Source of Adipose-Derived Mesenchymal Stem Cells.

Introduction. The Infrapatellar fat pad (IPFP) represents an emerging alternative source of adipose-derived mesenchymal stem cells (ASCs). We compared the characteristics and differentiation capacity of ASCs isolated from IPFP and SC. Materials and Methods. ASCs were harvested from either IPFP or SC. IPFPs were collected from patients undergoing total knee arthroplasty (TKA), whereas subcutaneous tissues were collected from patients undergoing lipoaspiration. Immunophenotypes of surface antigens were evaluated. Their ability to form colony-forming units (CFUs) and their differentiation potential were determined. The ASCs karyotype was evaluated. Results. There was no difference in the number of CFUs and size of CFUs between IPFP and SC sources. ASCs isolated from both sources had a normal karyotype. The mesenchymal stem cells (MSCs) markers on flow cytometry was equivalent. IPFP-ASCs demonstrated significantly higher expression of SOX-9 and RUNX-2 over ASCs isolated from SC (6.19 ± 5.56-, 0.47 ± 0.62-fold; p value = 0.047, and 17.33 ± 10.80-, 1.56 ± 1.31-fold; p value = 0.030, resp.). Discussion and Conclusion. CFU assay of IPFP-ASCs and SC-ASCs harvested by lipoaspiration technique was equivalent. The expression of key chondrogenic and osteogenic genes was increased in cells isolated from IPFP. IPFP should be considered a high quality alternative source of ASCs.

Hematopoietic stem cell transplantation for homozygous ß-thalassemia and ß-thalassemia/hemoglobin E patients from haploidentical donors.

Thalassemia-free survival after allogeneic stem cell transplantation (SCT) is about 80-90% with either matched-related or -unrelated donors. We explored the use of a mismatched-related ('haplo- ') donor. All patients received two courses of pretransplant immunosuppressive therapy (PTIS) with fludarabine (Flu) and dexamethasone (Dxm). After two courses of PTIS, a conditioning regimen of rabbit antithymocyte globulin, Flu and IV busulfan (Bu) was given followed by T-cell-replete peripheral blood progenitor cells. GvHD prophylaxis consisted of cyclophosphamide (Cy) on days SCT +3 and +4 (post-Cy), and on day SCT +5 tacrolimus or sirolimus was started together with a short course of mycophenolate mofetil. Thirty-one patients underwent haplo-SCT. Their median age was 10 years (range, 2-20 years). Twenty-nine patients engrafted with 100% donor chimerism. Two patients suffered primary graft failure. Median time to neutrophil engraftment was 14 days (range, 11-18 days). Five patients developed mild to moderate, reversible veno-occlusive disease, while nine patients developed acute GvHD grade II. Only five patients developed limited-chronic GvHD. Projected overall and event-free survival rates at 2 years are 95% and 94%, respectively. The median follow up time is 12 months (range, 7-33 months).

Immunogenicity of a live-attenuated Japanese encephalitis vaccine in children and adolescents after hematopoietic stem cell transplantation.

There have been no recommendations for revaccination with the Japanese encephalitis (JE) vaccine in post-hematopoietic stem cell transplantation (HSCT) patients. This study aimed to measure the immunogenic response to a live-attenuated JE vaccine (SA 14-14-2) in post-HSCT patients. JE-specific neutralizing Ab titers were measured before and after the JE vaccination. The patients with Ab titers <10 at the 3-month time point received a second injection at 6 months. A total of 28 patients (male:female=11:17) with a median age of 13 years (4-21 years) were included. The underlying diseases were thalassemia (50%) and hematologic malignancies (50%). Ten patients (35.7%) had Ab titers above the preventive level before vaccination. Nine of 18 patients (50%) seroconverted at 3 months after a single JE vaccination, but only three of these patients had sustained protective Ab levels. Seven of nine patients (78%) seroconverted at 3 months after a second JE vaccine injection, and all of these patients sustained protective Ab levels at 12 months. In conclusion, post-HSCT patients had low seroconversion rates after a single dose of the live-attenuated JE vaccine. These patients may require at least two doses of the JE vaccine to ensure protective Ab levels.

Interphase-FISH screening for eight common rearrangements in pediatric B-cell precursor acute lymphoblastic leukemia.

INTRODUCTION: This is the first pilot study to screen multiple common genetic aberrations in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). METHODS: Thirty-two children with BCP-ALL were investigated for chromosomal rearrangements using interphase fluorescence in situ hybridization (FISH). Eight common translocations and rearrangements, including ETV6-RUNX1, TCF3-PBX1, BCR-ABL1, ETV6, TCF3, MLL, IGH@, and PAX5, were tested for using dual-color DNA probes. RESULTS: ETV6-RUNX1 was the most frequent translocation detected in 11 children (34.4%). Two patients with BCR-ABL1 (6.3%) and one with TCF3-PBX1 (3.1%) translocations were also observed. Using break-apart probes, 11 children (34.4%) had a positive FISH result for ETV6, two patients for IGH@ (6.3%), one patient for MLL (3.1%), and one patient for PAX5 rearrangements (3.1%). All patients with the ETV6-RUNX1 fusion were also identified by split signals for ETV6. Other abnormalities, including extra copies and deletion of genes, were observed within the range of 3.1-34.4%. Cytogenetics analysis showed a single case each of BCR-ABL1 fusion, MLL, and IGH@ rearrangements (3.1% each). ETV6-RUNX1 fusion and ETV6 split-apart rearrangements were not visible by cytogenetics. Likewise, one each of cases with TCF3-PBX1 fusion and with PAX5 split signal seen by FISH was not visible by cytogenetics. CONCLUSION: By using 8 FISH probes in conjunction cytogenetics for the detection of common aberrations, interphase FISH enhanced the detection of chromosomal rearrangements in children with BCP-ALL.

Polymorphism of glutathione S-transferase Omega gene: association with risk of childhood acute lymphoblastic leukemia.

PURPOSE: To evaluate the association between glutathione S-transferase Omega (GSTO) genes polymorphism and the susceptibility of acute lymphoblast leukemia (ALL). METHODS: The polymorphism of GSTO1 and GSTO2 genes were analyzed in 99 ALL patients compared with 100 healthy children by PCR-based restriction fragment length polymorphism (RFLP) analysis. RESULTS: GSTO1*A140D polymorphism was significantly associated with susceptibility to ALL (OR = 2.24, 95% CI = 1.16-4.35, P = 0.009) whereas, GSTO2*N142D genotype was significantly interacted with high risk group of childhood ALL (OR = 5.52, 95% CI = 1.72-17.71, P = 0.004). CONCLUSION: This study revealed gene polymorphism in glutathione S-transferase Omega class may be a risk factor to the development of acute childhood lymphoblastic leukemia.

Simple multiplex RT-PCR for identifying common fusion transcripts in childhood acute leukemia.

Nonrandom gene rearrangements have been demonstrated in leukemic cells at diagnosis. These genetic abnormalities are associated with specific types, clinical characteristics, and prognosis of acute leukemia. Common fusion transcripts in childhood acute lymphoblastic leukemia (ALL) are TEL-AML1, E2A-PBX, MLL-AF4, and BCR-ABL (p190) and in acute nonlymphoblastic leukemia (ANLL) are AML-ETO, PML-RARA, and CBFB-MYH11. Reverse transcription-polymerase chain reaction (RT-PCR) for detection of each individual fusion transcript is impractical and time consuming. The purpose of this study was to develop simple RT-PCR methods to identify common fusion transcripts of newly diagnosed acute leukemia in children. Total RNA was extracted from bone marrow samples of children diagnosed with acute leukemia. Multiplex RT-PCR panel A (ALL) included primers for TEL-AML1, E2A-PBX, MLL-AF4, and BCR-ABL (p190) whereas panel B (ANLL) composed of primers for AML-ETO, PML-RARA, and CBFB-MYH11. Known leukemic cell lines were used to serve as positive controls. Eighty three children diagnosed with ALL (n = 63) and ANLL (n = 20) were included in this study. Fusion transcripts could be identified using multiplex RT-PCR panel A for ALL and panel B for ANLL in 26/83 (31.3%) cases. In ALL samples, we found TEL-AML1 = 16/63 (25.4%), E2A-PBX = 3/63 (4.8%), MLL-AF4 = 1/63 (1.6%), and BCR-ABL = 1/63 (1.6%). Four cases of AML1-ETO (20%) and one PML-RARA (5%) were found in ANLL samples. In conclusion, our simple multiplex RT-PCR for detection of fusion transcripts in childhood acute leukemia was found to be a rapid, accurate, and effective method.

Rituximab as an adjuvant therapy to immune tolerance in a haemophilia A boy with high inhibitor titre.

We report a haemophilia A boy with high inhibitor titre (170 BU) who experienced five life-threatening bleeding episodes during a one-year period from 9 to 21 months. At the age of 22 months, he received rituximab (375 mg m(-2) per dose) at one- and three-week intervals, three courses each and alternative daily treatment with factor VIII concentrate at doses of 100 units kg(-1) for 24 weeks and 50 units kg(-1) for the following 28 weeks. Although the pretreatment inhibitor level of 4.5 BU showed an anamnestic response reaching the maximum level of 200 BU at the 9th week of treatment, it gradually declined to 30 BU at the 22nd week and was constantly maintained at 25-30 BU for the following 30 weeks. Only three bleeding episodes of two haematomas and one haemarthrosis were found during the one-year treatment period. No opportunistic infection occured during this period.

Chronic metabolic acidosis alters osteoblast differentiation from human mesenchymal stem cells.

Bone histology of distal renal tubular acidosis patients showed decreased bone formation with impaired bone matrix mineralization that is not entirely explained by an alteration in the mineral balance. Data from in vitro studies suggests a direct inhibitory effect of metabolic acidosis on osteoblast function. We investigated the effects of chronic metabolic acidosis on osteoblast differentiation from mesenchymal stem cells (MSCs). Human MSCs were allowed to differentiate into osteoblasts in culture. Concentrated hydrochloric acid was added to the medium to lower the bicarbonate concentration and pH. The expression of various osteoblastic genes and proteins and bone matrix mineralization were examined. Chronic metabolic acidosis enhanced the messenger RNA (mRNA) and protein expression of early osteoblast transcription factor, runx-2, whereas inhibiting osterix and having no effect on ATF-4. The expression of type I collagen, the most abundant bone matrix protein, was increased following the same pattern of runx-2. Likewise, metabolic acidosis slightly enhanced the expression of mature osteoblastic gene, osteocalcin. Study on mineralization revealed suppressed alkaline phosphatase mRNA and enzyme activity. Despite the augmented collagen deposit in acidic culture, bone matrix mineralization was impaired. In conclusion, chronic metabolic acidosis alters osteoblast differentiation from MSCs through its diverse effect on osteoblastic genes and proteins resulting in an impairment of bone formation.

Polymorphisms of drug-metabolizing enzymes and risk of childhood acute lymphoblastic leukemia.

The involvement of phase I and II enzymes is well documented in the metabolism of a wide range of drugs and xenobiotics. Single-nucleotide polymorphisms (SNPs) of these enzymes are also known to alter their protein expression and function. Moreover, genetic susceptibility and environmental exposure have been proposed to be an etiology of cancer. We hypothesized that polymorphisms of these enzymes might affect the risk of childhood acute lymphoblastic leukemia (ALL). CYP 1A1, CYP 3A4*1B, CYP 3A5*3, CYP 3A5*6, GSTM1, and GSTT1 polymorphisms were genotyped by using PCR-RFLP in 107 children with ALL and 320 healthy controls. Allele and genotype frequencies of each of the SNPs were compared between two groups. It was found that the allele frequencies of CYP 1A1*1, *2A, *2B, and *4 were not different between cases and controls. CYP 3A4*1B allele frequency was only 0.8% and 0.9% in ALL and controls, respectively. CYP 3A5*1/*1, *1/*3, and *3/*3 genotype frequencies showed no statistically significant difference between patients and controls. CYP 3A5*6 was not detected in our population. The GSTM1 null genotype was significantly increased in children with ALL (OR 1.7; 95% CI, 1.0, 2.7). In contrast, the GSTT1 null genotype did not show this effect. Our data thus demonstrate that the GSTM1 null genotype might increase the risk of childhood ALL in a Thai population.

Outcome of transplantation with unrelated donor bone marrow in children with severe thalassaemia.

SUMMARY: We conducted a study of unrelated donor bone marrow transplantation (BMT) in 11 children with severe thalassaemia. The conditioning regimen consisted of busulphan, cyclophosphamide and antilymphocyte globulin. All received T-cell nondepleted bone marrow. The median marrow-nucleated cell dose was 4.9 x 10(8) /kg (range; 3.5-8.0 x 10(8) /kg). Median time of granulocyte recovery was 16 days (range; 13-21 days), and of platelet recovery was 39 days (range; 14-196). Grade 2-4 acute graft-versus-host disease (GVHD) developed in six patients (54%), and grade 3-4 in one patient (9%). Three (27%) of 11 evaluable patients had chronic GVHD (limited stage). All 11 patients are alive without thalassaemia after a median follow-up time of 397 days (range; 171-814 days). This study lends support to consideration of unrelated donor BMT as an acceptable therapy to cure severe thalassaemia especially in patients who are young and do not yet show irreversible severe complications of iron overload.

Full chimerism in nonmyeloablative stem cell transplantation in a beta-thalassemia major patient (class 3 Lucarelli).

Bone marrow transplantation is the only therapeutic option that can eliminate thalassemic disease. Early results indicated that children in class 3 Lucarelli had a much worse outcome because of high nonrejection mortality and high rejection rate. We therefore tried to investigate a nonmyeloablative stem cell transplantation (NST) approach for such a disease in order to reduce mortality and rejection. We report here the case of successful NST in a 10-year-old girl who had class 3 Lucarelli beta-thalassemia major. The conditioning regimen consisted of busulfan, fludarabine, antilymphocyte globulin and total lymphoid irradiation. Her GVHD prophylaxis included mycophenolate mofetil and cyclosporin. The patient had full donor engraftment without acute and chronic GVHD. She is now alive and well and remains disease-free 1 year after transplant.

Successful treatment of refractory autoimmune haemolytic anaemia in a post-unrelated bone marrow transplant paediatric patient with rituximab.

Here, we report a case of paediatric beta-thalassaemia major patient who underwent unrelated T cell-non- depleted bone marrow transplantation and developed a complication of autoimmune haemolytic anaemia (AIHA) refractory to corticosteroid and intravenous immunoglobulin therapy. After this child received two doses (375 mg/m2/dose) of rituximab (anti-CD20 monoclonal antibody), his AIHA was resolved.

The usefulness of X-linked polymorphic loci as gene markers to track X allele and chimerism in a post-allogeneic peripheral blood stem cell transplant patient with Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS), an X-linked recessive disorder, is characterized by progressive T-cell immunodeficiency. Laboratory findings generally demonstrate reduced response to T-cell mitogens, markedly decreased serum concentration of IgM, and thrombocytopenia with small platelet volume. Allogeneic HLA-matched sibling bone marrow transplantation (BMT) can correct this disorder. We report the usefulness of X-linked polymorphic loci to detect X-allele gene tracking among WAS siblings and chimerism between a pre- and post-allogeneic matched sibling peripheral blood stem cell transplantation (PBSCT). A 3 1/2 year old boy with clinical and laboratory findings consistent with WAS underwent allogeneic matched sibling PBSCT. We used BclI restriction fragment length polymorphism (RFLP) of intron 18 of factor VII gene and MseI RFLP of the 5' flanking region of factor IX gene to detect X-allele gene tracking among siblings and family members and chimerism in patients between pre-and post-allogeneic matched sibling PBSCT. We were able to demonstrate that determination of BclI and MseI RFLP can be employed to recognize the difference in X-allele genes between the recipient and donor for allogeneic matched sibling PBSCT. The authors also were able to demonstrate that these polymorphic loci can detect full chimerism of donor hematopoietic cells in recipient blood after allogeneic PBSCT. This finding was correlated with improvement of post-PBSCT clinical and laboratory findings. BclI and MseI RFLP associated with X-chromosome can effectively track X-allele, detect carrier state, and demonstrate the different X-allele among male siblings, and chimerism of hematopoietic cells between donors and recipients in a setting of allogeneic matched sibling BMT or PBSCT for X-linked hereditary diseases such as Wiskott-Aldrich syndrome.

Successful allogeneic peripheral blood stem cell transplantation in Wiskott-Aldrich Syndrome Patients: first report in Thailand.

Wiskott-Aldrich syndrome (WAS), an X-linked recessive disorder, is characterized by primary progressive T cell immunodeficiency, impaired antipolysaccharide antibody production, eczema, and thrombocytopenia. Stem cell transplantation is the only curative therapy. To evaluate the use of allogeneic peripheral stem cell transplantation (PBSCT) in this group of patients, we performed allogeneic PBSCT in two WAS patients (3 and 12 years old). The conditioning regimen consisted of busulfan 4 mg/kg/day for 4 days, and cyclophosphamide 50 mg/kg/day for 4 days. Graft-versus-host disease prophylaxis was consistent with cyclosporin A and methotrexate. Peripheral blood stem cells were collected from their brother donors (6 and 16 years old) by continuous flow leukapheresis after mobilization with granulocyte-colony-stimulating factor at a dose of 7.5 microg/kg/day for 5 days. Both recipients achieved neutrophils engraftment on days 11 and 12. The first patient achieved platelets engraftment on day 30. The second patient did not have platelet count below 20.0 x 10(9)/l during PBSCT procedure. Both did not develop acute or chronic graft-versus-host disease. At present, they are healthy after PBSCT. The follow up time after transplantation is 1,170 days and 269 days, respectively. Allogeneic PBSCT is economically feasible for WAS. The cost of PBSCT in Thailand is 20 to 30% less than bone marrow and cord blood stem cell transplantation. The cost of the transplant procedure for each patient in Thailand is US $ 12,000. This study is the first report of a successful stem cell transplantation in WAS patients in Thailand.