Thalassemia-free and graft-versus-host-free survival: outcomes of hematopoietic stem cell transplantation for thalassemia major, Turkish experience.

We report the national data on the outcomes of hematopoietic stem cell transplantation (HSCT) for thalassemia major (TM) patients in Turkey on behalf of the Turkish Pediatric Stem Cell Transplantation Group. We retrospectively enrolled 1469 patients with TM who underwent their first HSCT between 1988 and 2020 in 25 pediatric centers in Turkey. The median follow-up duration and transplant ages were 62 months and 7 years, respectively; 113 patients had chronic graft versus host disease (cGVHD) and the cGVHD rate was 8.3% in surviving patients. Upon the last visit, 30 patients still had cGvHD (2.2%). The 5-year overall survival (OS), thalassemia-free survival (TFS) and thalassemia-GVHD-free survival (TGFS) rates were 92.3%, 82.1%, and 80.8%, respectively. cGVHD incidence was significantly lower in the mixed chimerism (MC) group compared to the complete chimerism (CC) group (p < 0.001). In survival analysis, OS, TFS, and TGFS rates were significantly higher for transplants after 2010. TFS and TGFS rates were better for patients under 7 years and at centers that had performed over 100 thalassemia transplants. Transplants from matched unrelated donors had significantly higher TFS rates. We recommend HSCT before 7 years old in thalassemia patients who have a matched donor for improved outcomes.

Prognostic factors for survival in children who relapsed after allogeneic hematopoietic stem cell transplantation for acute leukemia.

BACKGROUND: Post-transplant relapse has a dismal prognosis in children with acute leukemia undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Data on risk factors, treatment options, and outcomes are limited. PROCEDURE: In this retrospective multicenter study in which a questionnaire was sent to all pediatric transplant centers reporting relapse after allo-HSCT for a cohort of 938 children with acute leukemia, we analyzed 255 children with relapse of acute leukemia after their first allo-HSCT. RESULTS: The median interval from transplantation to relapse was 180 days, and the median follow-up from relapse to the last follow-up was 1844 days. The 3-year overall survival (OS) rate was 12.0%. The main cause of death was disease progression or subsequent relapse (82.6%). The majority of children received salvage treatment with curative intent without a second HSCT (67.8%), 22.0% of children underwent a second allo-HSCT, and 10.2% received palliative therapy. Isolated extramedullary relapse (hazard ratio (HR): 0.607, P = .011) and relapse earlier than 365 days post-transplantation (HR: 2.101, P < .001 for 0-180 days; HR: 1.522, P = .041 for 181-365 days) were found in multivariate analysis to be significant prognostic factors for outcome. The type of salvage therapy in chemosensitive relapse was identified as a significant prognostic factor for OS. CONCLUSION: A salvage approach with curative intent may be considered for patients with post-transplant relapse, even if they relapse in the first year post-transplantation. For sustainable remission, a second allo-HSCT may be recommended for patients who achieve complete remission after reinduction treatment.

Stem cells combined 3D electrospun nanofibrous and macrochannelled matrices: a preliminary approach in repair of rat cranial bones.

Repair of cranial bone defects is an important problem in the clinical area. The use of scaffolds combined with stem cells has become a focus in the reconstruction of critical-sized bone defects. Electrospinning became a very attracting method in the preparation of tissue engineering scaffolds in the last decade, due to the unique nanofibrous structure of the electrospun matrices. However, they have a limitation for three dimensional (3D) applications, due to their two-dimensional structure and pore size which is smaller than a cellular diameter which cannot allow cell migration within the structure. In this study, electrospun poly(ε-caprolactone) (PCL) membranes were spirally wounded to prepare 3D matrices composed of nanofibers and macrochannels. Mesenchymal stromal/stem cells were injected inside the scaffolds after the constructs were implanted in the cranial bone defects in rats. New bone formation, vascularisation and intramembranous ossification of the critical size calvarial defect were accelerated by using mesenchymal stem cells combined 3D spiral-wounded electrospun matrices.

PKNOX2 expression and regulation in the bone marrow mesenchymal stem cells of Fanconi anemia patients and healthy donors.

HOX and TALE transcription factors are important regulators of development and homeostasis in determining cellular identity. Deregulation of this process may drive cancer progression. The aim of this study was to investigate the expression of these transcription factors in the bone marrow derived mesenchymal stem cells (BM-MSCs) of Fanconi anemia (FA) patients, which is a cancer-predisposing disease. Expression levels of HOX and TALE genes in BM-MSCs were obtained from FA patients and healthy donors by RT-qPCR and highly conserved expression levels were observed between patient and donor cells, except PKNOX2, which is a member of TALE class. PKNOX2 was significantly downregulated in FA cells compared to donors (P < 0.05). PKNOX2 expression levels did not change with diepoxybutane (DEB), a DNA crosslinking agent, in either donor or FA cells except one patient's with a truncation mutation of FANCA. A difference of PKNOX2 protein level was not obtained between FA patient and donor BM-MSCs by western blot analysis. When human TGF-ß1 (rTGF-ß1) recombinant protein was provided to the cultures, PKNOX2 as well as TGF-ß1 expression increased both in FA and donor BM-MSCs in a dose dependent manner. 5 ng/mL rTGF-ß stimulation had more dominant effect on the gene expression of donor BM-MSCs compared to FA cells. Decreased PKNOX2 expression in FA BM-MSCs may provide new insights into the molecular pathophysiology of the disease and TGF-ß1 levels of the microenvironment may be the cause of PKNOX2 downregulation.

The Effects of Hypericum perforatum L. on the Proliferation, Osteogenic Differentiation, and Inflammatory Response of Mesenchymal Stem Cells from Different Niches.

The aim of this study is to demonstrate and compare the differentiation, proliferation, migration and inflammatory behavior of dental pulp- and bone marrow-derived mesenchymal stem cells (DP-MSCs and BM-MSCs) in response to a Hypericum perforatum ethanol extract. Using xCELLigence, a real-time monitoring system, a dose of 10 µg/mL was found to be the most efficient concentration for vitality. The IC50 values and doubling time were calculated. The results showed that H. perforatum L. was able to accelerate osteogenic differentiation in DP-MSCs, but calcium granulation was impaired in BM-MSCs. H. perforatum L.-induced migration increased when compared to the TNF-α-induced migration in a Transwell migration assay, and the IL-6 cytokine levels between cells also differed. It can be suggested that tissue memory is an important factor in MSCs, and that they differ in their response to external factors. In conclusion, H. perforatum L. can be considered an excellent osteoinductive agent for DP-MSCs but should not be used for BM-MSCs. Tissue-specific osteoinductive agents should be discussed in future studies.

Bone Marrow Mesenchymal Stem Cells Carrying FANCD2 Mutation Differ from the Other Fanconi Anemia Complementation Groups in Terms of TGF-ß1 Production.

Transforming growth factor beta (TGF-ß) secretion from cells in the bone marrow (BM) niche affects hematopoietic stem cell (HSC) fate and has a cardinal role in HSC quiescence. BM mesenchymal stem cells (BM-MSCs), a component of the BM niche, may produce abnormal levels of TGF-ß in Fanconi anemia (FA) and may play a role in bone marrow failure. Here, we molecularly and cellularly characterized FA BM-MSCs by addressing their immunophenotype, proliferation- and differentiation- capacity, reactive oxygen species (ROS) production, senescence activity as well as expression and secretion levels of TGF-ß isoforms. In ten FA patients, mutations were detected in FANCA (n = 7), FANCG (n = 1) and FANCD2 (n = 2) genes. The immunophenotype, with the exception of CD29, and differentiation capacity of FA BM-MSCs were similar to healthy donors. FA BM-MSCs showed decreased proliferation, increased ROS level and an arrest in G2 following DEB treatment. ß-galactosidase staining indicated elevated senescence of FANCD2-deficient cells. FA BM-MSCs displayed TGF-ß1 mRNA levels similar to donor BM-MSCs, and was not affected by DEB treatment. However, secretion of TGF-ß was absent in FA-D2 BM-MSCs. Absence of TGF-ß secretion may be related to early onset of senescence of the FANCD2-deficient BM-MSCs. The proliferative response of FA-D2 BM-MSCs to rTGF-ß1 was not different from FANCA-deficient and donor cells and raises the possibility that rTGF-ß1 may reverse the senescence of the FANCD2-deficient BM-MSCs which needs to be investigated further.

The clinical and laboratory evaluation of familial hemophagocytic lymphohistiocytosis and the importance of hepatic and spinal cord involvement: a single center experience.

Familial hemophagocytic lymphohistiocytosis is an autosomal recessive, life-threatening condition characterized by defective immune response. A retrospective analysis was performed on 57 patients diagnosed with familial hemophagocytic lymphohistiocytosis at Hacettepe University Pediatric Hematology Department, Ankara, Turkey. Mutation analysis was performed on 37 patients, and of these: 11 had UNC13D, 10 had PRF1 and 3 had STX11 gene mutation. Of these patients, 44% were found to have central nervous system involvement on admission and spinal cord involvement was also seen in 5 patients. Remission was achieved in 24 patients with the treatment, in a median time of 76 days (min-max: 15-705 days). Time to remission was prolonged 3.1 times in patients with a ferritin level 1500 mg/dL or more. When patients were grouped according to age [Group 1 (≤ 2 years), Group 2 (>2 years)]; patients in Group 1 had higher ferritin and aspartate aminotransferase levels but lower fibrinogen levels. The 5-year survival rate was also lower in Group 1. When patients in Group 1 were divided into two sub-groups according to hepatic involvement, the 5-year survival rate of patients who had hepatic involvement was significantly lower than those patients without hepatic involvement (0.7%, 27%, respectively) (P=0.002). The 5-year survival rate of patients who underwent hematopoietic stem cell transplantation was significantly higher than the patients who didn't (44%, 16%, respectively) (P=0.02). In conclusion, age two years and under, ferritin level above 1500 mg/dL, spinal cord or hepatic involvement should be considered as poor prognostic factors in familial hemophagocytic lymphohistiocytosis.

Effects of Syzygium aromaticum, Cinnamomum zeylanicum, and Salvia triloba extracts on proliferation and differentiation of dental pulp stem cells.

INTRODUCTION: Hypersensitivity, local irritative and cytotoxic effects are known for the chemical components of Syzygium aromaticum and Cinnamomum zeylanicum contained in dental materials. However, there is no intimate data in dentistry using the whole extracts of these plants and introducing new ones. Salvia triloba is a well-known anti-inflammatory plant that correspondingly could be used in several dental traumas. OBJECTIVES: We aimed to show and compare the effect of S. aromaticum, C. zeylanicum, and S. triloba extracts on dental pulp stem cells (DPSCs) proliferation, differentiation, and immune responses. MATERIAL AND METHODS: Using xCELLigence, a real time monitoring system, we obtained a growth curve of DPSCs with different concentrations of the Extracts. A dose of 10 µg/mL was the most efficient concentration for vitality. Osteogenic differentiation and anti-inflammatory activities were determined by using an ELISA Kit to detect early and late markers of differentiation. RESULTS: The level of osteonectin (ON, early osteogenic marker) decreased, which indicated that the osteogenic differentiation may be accelerated with addition of extracts. However, the level of osteocalcin (OCN, late osteogenic marker and sign of calcium granulation) differed among the extracts, in which S. aromaticum presented the highest value, followed by S. triloba and C. zeylanicum. Surprisingly, the determined calcium granules were reduced in S. aromaticum and S. triloba. In response to tumor necrosis factor alpha (TNF-α), S. triloba-treated DPSCs showed the most reduced level of IL-6 cytokine level. We suggest C. zeylanicum as a promising osteogenic inducer and S. triloba as a potent anti-inflammatory agent, which could be used safely in biocomposite or scaffold fabrications for dentistry. CONCLUSIONS: Because calcium granule formation and cell viability play a critical role in hard tissue formation, S. aromaticum in dentistry should be strictly controlled, and the mechanism leading to reduced calcium granule formation should be identified.

Effects of Syzygium aromaticum, Cinnamomum zeylanicum, and Salvia triloba extracts on proliferation and differentiation of dental pulp stem cells

Abstract Hypersensitivity, local irritative and cytotoxic effects are known for the chemical components of Syzygium aromaticum and Cinnamomum zeylanicum contained in dental materials. However, there is no intimate data in dentistry using the whole extracts of these plants and introducing new ones. Salvia triloba is a well-known anti-inflammatory plant that correspondingly could be used in several dental traumas. Objectives: We aimed to show and compare the effect of S. aromaticum, C. zeylanicum, and S. triloba extracts on dental pulp stem cells (DPSCs) proliferation, differentiation, and immune responses. Material and Methods: Using xCELLigence, a real time monitoring system, we obtained a growth curve of DPSCs with different concentrations of the Extracts. A dose of 10 μg/mL was the most efficient concentration for vitality. Osteogenic differentiation and anti-inflammatory activities were determined by using an ELISA Kit to detect early and late markers of differentiation. Results: The level of osteonectin (ON, early osteogenic marker) decreased, which indicated that the osteogenic differentiation may be accelerated with addition of extracts. However, the level of osteocalcin (OCN, late osteogenic marker and sign of calcium granulation) differed among the extracts, in which S. aromaticum presented the highest value, followed by S. triloba and C. zeylanicum. Surprisingly, the determined calcium granules were reduced in S. aromaticum and S. triloba. In response to tumor necrosis factor alpha (TNF-α), S. triloba-treated DPSCs showed the most reduced level of IL-6 cytokine level. We suggest C. zeylanicum as a promising osteogenic inducer and S. triloba as a potent anti-inflammatory agent, which could be used safely in biocomposite or scaffold fabrications for dentistry. Conclusions: Because calcium granule formation and cell viability play a critical role in hard tissue formation, S. aromaticum in dentistry should be strictly controlled, and the mechanism leading to reduced calcium granule formation should be identified.

Beneficial Effect of the Nutritional Support in Children Who Underwent Hematopoietic Stem Cell Transplant.

OBJECTIVES: The aim of this study was to evaluate nutritional status in children who underwent hematopoietic stem cell transplant compared with a healthy control group. A secondary aim was to utilize mid-upper arm circumference as a measure of nutritional status in these groups of children. MATERIALS AND METHODS: Our study group included 40 children (18 girls, 22 boys) with mean age of 9.2 ± 4.6 years (range, 2-17 y) who underwent hematopoietic stem cell transplant. Our control group consisted of 20 healthy children (9 girls, 11 boys). The children were evaluated at admission to the hospital and followed regularly 3, 6, 9, and 12 months after discharge from the hospital. RESULTS: In the study group, 27 of 40 patients (67.5%) received nutritional support during hematopoietic stem cell transplant, with 15 patients (56%) receiving enteral nutrition, 6 (22%) receiving total parenteral nutrition, and 6 (22%) receiving enteral and total parenteral nutrition. Chronic malnutrition rate in the study group was 47.5% on admission to the hospital, with the control group having a rate of 20%. One year after transplant, the rate decreased to 20% in the study group and 5% in the control group. The mid-upper arm circumference was lower in children in the study group versus the control group at the beginning of the study (P < .05). However, there were no significant differences in mid-upper arm circumference measurements between groups at follow-up examinations (P > .05). During follow-up, all anthropometric measurements increased significantly in both groups. CONCLUSIONS: Monitoring nutritional status and initiating appropriate nutritional support improved the success of hematopoietic stem cell transplant and provided a more comfortable process during the transplant period. Furthermore, mid-upper arm circumference is a more sensitive, useful, and safer parameter that can be used to measure nutritional status of children who undergo hematopoietic stem cell transplant.

Factors associated with bone marrow stem cell yield for pediatric allogeneic stem cell transplantation: The impact of donor characteristics.

The aim of this study was to investigate the effects of donor characteristics on CD34+ cell yield in BM harvest. Between April 2010 and November 2013, consecutive donors who underwent BM harvesting in our BM transplantation unit were retrospectively investigated. Donors were classified into two groups: those who donated BM without mobilization (steady-state BM donors) and those who received G-CSF for stem cell mobilization (G-CSF-primed BM donors). Donor characteristics (age, gender, race, body weight, BMI, and laboratory factors including donor's leukocyte, platelet, and monocyte) and their relationship with total nuclear cell and CD34+ cell numbers has been evaluated. A total of 64 healthy related donors (29 males/35 females, median age 11.2 years; 49 [76.6%] younger than 18 and 36 [56.3%] younger than 12 years) were included in the study. The median CD34+ cell yield in the harvest was 0.12×106 /L (0.02-0.21) in SS-BM donors and 0.18×106 /L (0.09-0.67) in GP-BM donors (P=.03). Median of CD34+ cell count given to recipients was 2.6×106 /recipient body weight (1.3-19.3) in SS-BM yields and 3.8×106 /recipient body weight (1.1-10.2) in GP-BM yields, respectively. Multiple regression analysis showed that donor height and pre-G-CSF platelet were the most important parameters to obtain a sufficient BM harvest. Our data suggest that the shorter donors and the donors with higher thrombocyte counts may offer more hematopoietic stem cell. The height and thrombocyte count of the donors should be taken into consideration before planning the targeted CD34+ cell count especially for pediatric donors.

Thymbra Spicata Var. Intricata Induces Mesenchymal Stem Cell Proliferation and Osteogenic Differentiation

ABSTRACT A natural agent that maintains mesenchymal stem cell (MSCs) viability, promotes osteogenic differentiation while modulating the immunological response could achieve success in regeneration during healing and may also prevent bone resorption and improve regeneration. We aimed to demonstrate that a Thymbra spicata var. intricata extract could induce proliferation, differentiation, and modulate the immune responses of mesenchymal stem cells (MSCs). Using xCELLigence, a real-time monitoring system, we obtained a growth curve of MSCs. A dose of 10 µg/mL was the most efficient concentration for vitality. Osteogenic differentiation and antiinflammatory activities were determined by using an ELISA Kit to detect early and late markers of differentiation. The Osteonectin (ON, early osteogenic marker) level decreased while the Osteocalcin (OCN, late osteogenic marker) level increased in the T. spicata var. intricata treated group, suggesting that T. spicata var. intricata may accelerate osteogenic differentiation. Reduced level of the IL-6 cytokine in repsonse to TNF-α was evident. T. spicata var. intricata could be a promising osteogenic inducer in dentistry and could be used safely in biocomposites or scaffold fabrications.

Stepwise diet management in pediatric gastrointestinal graft versus host disease.

Gastrointestinal tract is one of the major systems affected by graft-versus-host disease (GVHD). Injury to the gut during conditioning therapy before stem-cell transplantation (SCT) plays a pivotal role in the initiation of inflammatory stimuli. We reviewed medical records of the patients who underwent SCT between April 2010 and June 2013 in our center. A stepwise upgrade diet was given to the children with acute GI-GVHD (Gastrointestinal GVHD) including parenteral and enteral nutrition. A total of 105 patients underwent SCT and seven patients developed grade III-IV acute GI-GVHD. Total parenteral nutrition (TPN) was initiated to all patients after the diagnosis of GI-GVHD and minimal enteral nutrition (1-2 ml/kg/day standard pediatric enteral formula/special meat soup) was given to the patients. GI-GVHD improved in all patients with no change in body weight, and recovery to a normal diet took 10-30 days. Stepwise diet management of oral nutrition contributed to rapid improvement of grades III-IV acute GI-GVHD.

Lactobacillus rhamnosus could inhibit Porphyromonas gingivalis derived CXCL8 attenuation.

UNLABELLED: An increasing body of evidence suggests that the use of probiotic bacteria is a promising intervention approach for the treatment of inflammatory diseases with a polymicrobial etiology. P. gingivalis has been noted to have a different way of interacting with the innate immune response of the host compared to other pathogenic bacteria, which is a recognized feature that inhibits CXCL8 expression. OBJECTIVE: The aim of the study was to determine if P. gingivalis infection modulates the inflammatory response of gingival stromal stem cells (G-MSSCs), including the release of CXCL8, and the expression of TLRs and if immunomodulatory L. rhamnosus ATCC9595 could prevent CXCL8 inhibition in experimental inflammation. MATERIAL AND METHODS: G-MSSCs were pretreated with L. rhamnosus ATCC9595 and then stimulated with P. gingivalis ATCC33277. CXCL8 and IL-10 levels were investigated with ELISA and the TLR-4 and 2 were determined through flow cytometer analysis. RESULTS: CXCL8 was suppressed by P. gingivalis and L. rhamnosus ATCC9595, whereas incubation with both strains did not abolish CXCL8. L. rhamnosus ATCC9595 scaled down the expression of TLR4 and induced TLR2 expression when exposed to P. gingivalis stimulation (p<0.01). CONCLUSIONS: These findings provide evidence that L. rhamnosus ATCC9595 can modulate the inflammatory signals and could introduce P. gingivalis to immune systems by inducing CXCL8 secretion.

Hematopoietic cell transplantation activity of Turkey in 2014: Ongoing increase in HCT rates.

Hematopoietic cell transplantation is an established treatment option with curative potential for a variety of clinical conditions. The last decade especially witnessed a remarkable increase in HCT activity in Turkey. In 2014, 696 pediatric and 2631 adult (total 3327) HCT were performed in Turkey. Corresponding transplant rates per 10 million inhabitants for autologous-HCT and allogeneic-HCT were 226 and 202, respectively. Total HCT procedures in Turkey increased 177% in the last 5 years and 791% in the last 14 years. This report focuses mainly on HCT activity of Turkey in 2014 based on the national HCT registry and presents a general picture of national HCT activity.

Lactobacillus rhamnosus could inhibit Porphyromonas gingivalis derived CXCL8 attenuation

ABSTRACT An increasing body of evidence suggests that the use of probiotic bacteria is a promising intervention approach for the treatment of inflammatory diseases with a polymicrobial etiology. P. gingivalis has been noted to have a different way of interacting with the innate immune response of the host compared to other pathogenic bacteria, which is a recognized feature that inhibits CXCL8 expression. Objective The aim of the study was to determine if P. gingivalis infection modulates the inflammatory response of gingival stromal stem cells (G-MSSCs), including the release of CXCL8, and the expression of TLRs and if immunomodulatory L. rhamnosus ATCC9595 could prevent CXCL8 inhibition in experimental inflammation. Material and Methods G-MSSCs were pretreated with L. rhamnosus ATCC9595 and then stimulated with P. gingivalis ATCC33277. CXCL8 and IL-10 levels were investigated with ELISA and the TLR-4 and 2 were determined through flow cytometer analysis. Results CXCL8 was suppressed by P. gingivalis and L. rhamnosus ATCC9595, whereas incubation with both strains did not abolish CXCL8. L. rhamnosus ATCC9595 scaled down the expression of TLR4 and induced TLR2 expression when exposed to P. gingivalis stimulation (p<0.01). Conclusions These findings provide evidence that L. rhamnosus ATCC9595 can modulate the inflammatory signals and could introduce P. gingivalis to immune systems by inducing CXCL8 secretion.

Mesenchymal stem cell application in children with subacute sclerosing panencephalitis.

Subacute sclerosing panencephalitis (SSPE) is a serious, often fatal disease that responds poorly to current treatment modalities. Recently, the ability of mesenchymal stem cells (MSCs) to produce neurotrophic factors and inflammatory molecules has placed them among potential treatment agents for neurological conditions. We report the results of four patients treated with MSC for SSPE. The patients were followed up clinically, and by periodical laboratory evaluations, magnetic resonance imaging (MRI), and electroencephalography. One patient deteriorated to stage III of the disease, two patients remained in the same stage, and one died from disease progression and respiratory problems. Neurological findings and electroencephalography scores were consistent with the clinical course of the patient whereas MRI showed new inflammatory lesions in two patients. This is the first report of the application of MSC in SSPE. No benefit is demonstrated.

Venous Thromboembolism after Allogeneic Pediatric Hematopoietic Stem Cell Transplantation: A Single-Center Study.

INTRODUCTION: Venous thromboembolism (VTE) in children who undergo hematopoietic stem cell transplantation (HSCT) has high morbidity. The aim of this study is to assess the incidence of VTE in allogeneic pediatric HSCT recipients and the contribution of pretransplant prothrombotic risk factors to thrombosis. METHODS: We retrospectively evaluated 92 patients between April 2010 and November 2012 undergoing allogeneic HSCT who had completed 100 days post-HSCT. Before HSCT, coagulation profiles; acquired and inherited prothrombotic risk factors including factor V Leiden, prothrombin G20210A, methylenetetrahydrofolate reductase (MTHFR) C677T, and MTHFR A1298C mutations; and serum homocysteine and lipoprotein(a), plasma antithrombin III, protein C, and protein S levels were obtained from all patients. RESULTS: In the screening of thrombophilia, 8 patients (9%) were heterozygous for factor V Leiden, 5 (6%) were homozygous for MTHFR 677TT, 12 (14%) were homozygous for MTHFR 1298CC, and 2 (2%) were heterozygous for prothrombin G20210A mutation. We observed VTE in 5 patients (5.4%); a prothrombotic risk factor was found in 3 out of these 5 patients, while 4 out of 5 patients had central venous catheters. It was determined there was no significant relationship between VTE and inherited prothrombotic risk factors. DISCUSSION AND CONCLUSION: VTE after HSCT seems to be a low-frequency event that may be due to low-dose, low-molecular-weight heparin prophylaxis, and the role of inherited prothrombotic risk factors cannot be entirely excluded without a prospective study.

Clinical outcomes and graft characteristics in pediatric hematopoietic stem cell transplantation: Effect of granulocyte-colony stimulating factor priming.

In this study, we aimed to determine the effect(s) of G-CSF priming on graft and transplantation parameters and compare these findings with those obtained without priming. A total of 64 pediatric patients transplanted from HLA-matched family donors were enrolled in the study. Twenty-nine patients received G-CSF primed marrow (G-BM group) and 35 patients received steady state bone marrow (S-BM group). Number of total nucleated cells (TNC) and CD34(+) cells, CFU-GM colony number, neutrophil and platelet engraftment times, total length of stay in hospital, overall and disease free survival, and occasions of acute and chronic GvHD has been compared between these two groups. Granulocyte colony stimulating factor primed bone marrow (G-BM) yielded higher numbers of CD34(+) cells, TNCs, and CFU-GM colony numbers compared to those obtained in S-BM. The neutrophil engraftment time, platelet engraftment time, length of stay in hospital, overall survival and disease free survival were not different between G-BM and S-BM groups. Also the cumulative incidence of grades II-IV acute and chronic GvHD were similar. It was observed that the use of G-CSF did not increase the risk of acute or chronic GvHD. We concluded that use of G-CSF for stem cell mobilization is an effective and safe method in children.