Hematopoietic cell transplantation in pediatric patients with acute leukemias or myelodysplastic syndrome using unrelated adult or umbilical cord blood donors in Brazil.

The choice of alternative donors for HCT for patients without an HLA-matched related donor depends on several factors. We compared major HCT outcomes in 212 consecutive children transplanted at 11 centers in Brazil for acute leukemia or MDS from an HLA-matched unrelated donor (MUD, n = 95), mismatched unrelated donor (MMUD, n = 47) or unrelated umbilical cord blood (UCB, n = 70). Most had ALL (61%), bone marrow (57%) as the graft source and 95% received a MAC regimen. The 3-year OS probability were 57, 55, and 37% after HCT from MUD, MMUD, and UCB, respectively (HR 1.68, 95%CI 1.07-2.63; P = .02). In comparison with MUD, OS was similar after transplantation of a ≥ 6/8 HLA-matched or a high cell dose (>5 × 107 TNC/kg) CB unit (HR 1.41, 95%CI 0.88-2.27; P = .15). NRM was higher for UCB (HR 3.90, 95%CI 1.43-10.7; P = .01) but not for MMUD (HR 1.03, 95%CI 0.53-2.00; P > .20). Advanced disease (HR 2.05, 95%CI 1.26-3.33; P < .001) and UCB with high probability of being < 6/8 HLA-matched (HR 5.34, 95%CI 2.0-13.9; P < .001) were associated with higher mortality. Relapse and acute GVHD were similar among groups, while PGF was higher among UCB transplants (P = .002) and chronic GVHD among MMUD group (HR 2.88, 95% CI 1.05-7.88; P = .04). Our results suggest that in Brazil HCT outcomes performed with MMUD and MUD donors were comparable, while with UCB units < 6/8 HLA-matched were associated with higher NRM for children with acute leukemia or MDS.

Translation, Cross-Cultural Adaptation, and Validation of the Lee Chronic Graft-versus-Host Disease Symptom Scale in a Brazilian Population.

The Lee Chronic Graft-versus-Host Disease (GVHD) Symptom Scale is a patient-reported instrument developed and validated in English to measure the symptoms and functional impact of cGVHD. This tool has not yet been validated in a Latin American population, however. The Brazil-Seattle Chronic GVHD Consortium conducted a multicenter study at 5 Brazilian institutions to validate the Lee cGVHD Symptom Scale in adults with cGVHD. Study objectives included the translation and validation of the instrument in Brazilian Portuguese and evaluation of the correlation with other quality of life (QoL) tools, including the Medical Outcomes Study Short Form 36 (SF-36) and Functional Assessment of Chronic Illness Therapy with Bone Marrow Transplant subscale (FACT-BMT). Translation and validation were done according to the American Association of Orthopedic Surgeons Outcome Committee guidelines. Spearman's correlation coefficient was used to measure construct validity. Reliability was assessed using Cronbach's α and intraclass correlation coefficients. Between April 2011 and August 2012, 47 patients with cGVHD based on the 2005 National Institutes of Health criteria (29 males [62%], 18 females [38%]; median age, 48 years; range, 23 to 69 years) were enrolled in this study. The reliability of the Lee cGVHD Symptom Scale was adequate (Cronbach's α = 0.62 to 0.83). The correlations between similar domains of the Lee cGVHD Symptom Scale, SF-36, and FACT-BMT were moderate to high. Our data indicate that the Brazilian Portuguese version of the Lee cGVHD Symptom Scale is valid and reliable and can be used in clinical trials of cGVHD in Brazil.

Survival and graft-versus-host disease in patients receiving peripheral stem cell compared to bone marrow transplantation from HLA-matched related donor: retrospective analysis of 334 consecutive patients.

OBJECTIVES: The objective of this study was to compare the major transplant outcomes between patients receiving hematopoietic stem cell transplantation (HSCT) from bone marrow (BM) or peripheral blood stem cells (PBSC). METHODS: All consecutive HSCT patients using BM or PBSC from an HLA-matched related donors for haematological malignancies after high intensity conditioning at seven Brazilian transplant centres between January 2008 and December 2009 were retrospectively evaluated. RESULTS: In the study period, 334 patients were treated in the centres and included in the evaluation. The cumulative incidence of grades II-IV and III-IV acute graft-versus-host disease (GVHD) at one year was 36.7% and 9.7% for BM recipients and 34.4% and 15.1% for PBSC recipients, respectively (not statistically different). The cumulative incidence of chronic GVHD at three years was 53.7% and 79.8% (HR 1.93; 95% CI 1.38-2.69, P < 0.001) for BM and PBSC, respectively. Median overall survival was 2.85 and 2.39 years for BM and PBSC recipients, respectively (HR 1.19; 95% CI, 0.84-1.68, P = 0.34). CONCLUSIONS: Our results confirm previous findings of increased chronic GVHD incidence in patients receiving PBSC when compared to patients receiving BM as the graft source in HSCT. Acute GVHD incidence, progression-free survival and overall survival were not different between the groups.

Evaluation of intracellular and extracellular trehalose as a cryoprotectant of stem cells obtained from umbilical cord blood.

Cord blood is a source of hematopoietic stem cells used in transplantation in which hematopoietic reconstitution is necessary. This transplant modality requires the cryopreservation of hematopoietic stem cells (HSCs). Dimethyl sulfoxide has been used as a cryoprotectant (CPA) in the cryopreservation of HSCs; however, it has been demonstrated that Me2SO exhibits toxic side effects to the human body. Due to its stability upon freezing, disaccharides such as trehalose have been investigated as a cryoprotectant. This study investigated the hypothesis that a cryopreservation solution containing intracellular and extracellular trehalose improves the recovery of stem cells after cryopreservation. After thawing, the cells were tested for their viability using the 7AAD stain, CD45+/CD34+ cells were assessed using flow cytometry and the MTT viability assay, and the proportion of hematopoietic progenitor cells was measured using the CFU assay. Our results showed the effectiveness of the solution containing intracellular and extracellular trehalose in the cryopreservation of cord blood cells, demonstrating that trehalose may be an optimal cryoprotectant when present both inside and outside of cells.

Age-related changes in natural killer cell receptors from childhood throughold age

Most studies on natural killer (NK) cells and aging have focused on overall cell numbers and global cytotoxicactivity. NK cell functions are controlled by surface receptors belonging to three major families: killer cellimmunoglobulin-like receptors (KIRs), natural cytotoxicity receptors (NCRs), and C-type lectins. The expressionof these receptors was investigated from childhood through old age in T, NKT- andNKcells and also in theCD56dim (cytotoxic) and CD56bright (responsible for cytokine production) NK cell subsets. A decrease in theexpression of activating receptors (NKp30 and NKp46) was observed in NK cells in elderly individuals. KIRexpression was increased only in the CD56bright subset. Children presented similar results regarding expressionof NKp30 and KIR, but not NKp46.NKG2Dexpression was decreased in T cells of elderly subjects. Analysisof KIR genotype revealed that KIR2DL5 and KIR2DS3 were significantly associated with old age. Cytotoxicactivity was preserved from childhood through old age, suggesting that the increase of the absolute numberof CD56dim, observed in elderly, may represent a compensatory mechanism for the receptor expressionalterations. This initial study provides the framework for more focused studies of this subject, which arenecessary to determine whether the changing balance of NK receptor expression may influence susceptibilityto infectious, inflammatory, and neoplastic diseases.(AU)

Quantitative and qualitative differences in use and trends of hematopoietic stem cell transplantation: a Global Observational Study.

Fifty-five years after publication of the first hematopoietic stem cell transplantation this technique has become an accepted treatment option for defined hematologic and non-hematologic disorders. There is considerable interest in understanding differences in its use and trends on a global level and the macro-economic factors associated with these differences. Data on the numbers of hematopoietic stem cell transplants performed in the 3-year period 2006-2008 were obtained from Worldwide Network for Blood and Marrow Transplantation member registries and from transplant centers in countries without registries. Population and macro-economic data were collected from the World Bank and from the International Monetary Fund. Transplant rates were analyzed by indication, donor type, country, and World Health Organization regional offices areas and related to selected health care indicators using single and multiple linear regression analyses. Data from a total of 146,808 patients were reported by 1,411 teams from 72 countries over five continents. The annual number of transplants increased worldwide with the highest relative increase in the Asia Pacific region. Transplant rates increased preferentially in high income countries (P=0.02), not in low or medium income countries. Allogeneic transplants increased for myelodysplasia, chronic lymphocytic leukemia, acute leukemias, and non-malignant diseases but decreased for chronic myelogenous leukemia. Autologous transplants increased for autoimmune and lymphoproliferative diseases but decreased for leukemias and solid tumors. Transplant rates (P<0.01), donor type (P<0.01) aand disease indications (P<0.01) differed significantly between countries and regions. Transplant rates were associated with Gross National Income/capita (P<0.01) but showed a wide variation of explanatory content by donor type, disease indication and World Health Organization region. Hematopoietic stem cell transplantation activity is increasing worldwide. The preferential increase in high income countries, the widening gap between low and high income countries and the significant regional differences suggest that different strategies are required in individual countries to foster hematopoietic stem cell transplantation as an efficient and cost-effective treatment modality.

The Interplay of Cesarean-Section Delivery and First-Birth Order as Risk Factors in Acute Lymphoblastic Leukemia.

BACKGROUND: Childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) has been associated with early-life exposures, including birth by cesarean section (C-section), and a deficit of social exposure (first child). These exposures as proxies for microbiome acquisition in infancy are essential to prime the immune system and restrain later dysregulated immune responses that can trigger ALL in susceptible individuals. We tested risk factors pertaining to immune stimulation that may impact BCP-ALL development. METHODS: Cases comprised 1,126 children (0-12 years) with ALL (BCP-ALL: 78.5%) from the EMiLI study group in Brazil (2002-2020). Age- and sex-matched controls (n = 2,252) were randomly selected from healthy children whose mothers participated in the National Placental and Umbilical Cord Blood Bank donation. Multiple logistic regression was run fitted and adjusted for selected covariates models. RESULTS: C-section delivery was associated with increased risk for ALL [odds ratio (OR) ALL: 1.10; 95% confidence intervals (CI), 1.04-1.15; ORBCP-ALL: 1.09; 95% CI, 1.03-1.14], as well as being the firstborn child. Interaction analysis showed a significant effect of first birth on the observed C-section associations (P < 0.0001). Indeed, high-risk children, namely, firstborn children delivered via C-section were at increased risk for ALL (OR: 2.33; 95% CI, 2.40-4.84) compared with non-first, vaginally born children. An increased risk was found for firstborn children delivered by C-section and non-breastfed with ALL (ORALL: 2.32; 95% CI, 1.27-4.24; ORBCP-ALL: 2.37; 95% CI, 1.18-4.76). CONCLUSIONS: Our observations are in accord with the prediction that exposures determining microbiome composition and adrenal pathway in infancy contribute to the risk of BCP-ALL. IMPACT: These findings encourage the exploration of potential preventive interventions. See related commentary by Wiemels and Gallant, p. 292.

Different outcomes between cyclophosphamide plus horse or rabbit antithymocyte globulin for HLA-identical sibling bone marrow transplant in severe aplastic anemia.

The standard regimen for HLA-identical sibling bone marrow transplant (BMT) in severe aplastic anemia (SAA) is cyclophosphamide (Cy) and horse antithymocyte globulin (ATG). Horse ATG has been replaced by rabbit ATG in many countries due to the unavailability of the former product. This study was designed to assess if these ATG preparations are interchangeable in the preparative regimen for matched related BMT in SAA. Forty consecutive BMTs were retrospectively analyzed: 20 received Cy plus horse ATG and 20 received Cy plus rabbit ATG as the preparative regimen. Conditioning with rabbit ATG was protective against acute graft-versus-host disease (aGVHD) grades II-IV and moderate-severe chronic GVHD (cGVHD), with incidence rates of 0% versus 35.2% (P = .009) and 0% versus 34.0% (P = .04), respectively. On day +100, the probability of proven/probable invasive fungal disease (IFD) was higher in patients conditioned with rabbit ATG, 31.2% versus 5.5%, respectively (P = .04). Earlier cytomegalovirus (CMV) reactivation (40 versus 50 days; P = .02) was observed with rabbit ATG. An inferior lymphocyte count on days +30 (0.360 versus 0.814 × 10(9)/L; P = .01) and +90 (0.744 versus 1.330 × 10(9)/L; P = .006) was noticed in recipients of rabbit ATG. The incidence of stable mixed chimerism was higher in recipients of rabbit ATG (18.2% versus 80%, respectively; P = .004). These results suggest that horse and rabbit ATG preparations have different biological and clinical properties and should not be used interchangeably in the preparative regimen for related BMT in SAA.

Serum ferritin as risk factor for sinusoidal obstruction syndrome of the liver in patients undergoing hematopoietic stem cell transplantation.

Hepatic sinusoidal obstruction syndrome (SOS) is a serious complication in hematopoietic stem cell transplant (HSCT) recipients. To determine the impact of pretransplantation hyperferritinemia on the risk of SOS after HSC transplantation, we retrospectively studied 427 HSCT recipients (179 autologous and 248 allogeneic). Serum ferritin levels were measured before transplantation. Patients with and without a diagnosis of SOS were compared regarding demographics; underlying disease; transplant characteristics; receipt of imatinib, busulfan, total body irradiation, gemtuzumab, vancomycin, acyclovir, or methotrexate; and baseline serum ferritin. Univariate and multivariate (stepwise logistic regression) analyses were performed. SOS was diagnosed in 88 patients (21%) at a median of 10 days (range, 2-29 days) after transplantation. By multivariate analysis, allogeneic HSC transplantation (odds ratio [OR] = 8.25; 95% confidence interval [95% CI], 3.31-20.57), receipt of imatinib (OR = 2.60; 95% CI, 1.16-5.84), receipt of busulfan (OR = 2.18; 95% CI, 1.25-3.80), and ferritin serum level higher than 1000 ng/dL (OR = 1.78; 95% CI, 1.02-3.08) were risk factors for SOS. A ferritin serum level higher than 1000 ng/dL in the pretransplantation period is an independent risk factor for SOS. The results suggest the need for prospective studies addressing the use of iron chelation in the pretransplantation period.

SUZ12 is a candidate target of the non-canonical WNT pathway in the progression of chronic myeloid leukemia.

Polycomb proteins form multiprotein complexes that repress target genes by chromatin remodeling. In this work, we report that the SUZ12 polycomb gene is over-expressed in bone marrow samples of patients at the blastic phase of chronic myeloid leukemia. We also found a direct interaction between polycomb group genes and the WNT signaling pathway in chronic myeloid leukemia transformation. Electrophoretic mobility shift assay (EMSA), Chromatin immunoprecipitation assay (ChIP), and mass spectrometry assays identified noncanonical WNT pathway members, such as WNT5A and WNT11, bound to the SUZ12 promoter. Immunohistochemistry and immunofluorescence with WNT5A and WNT11 antibodies confirmed nuclear localization. Knockdown of WNTs 1, 5A, and 11 with RNAi approaches showed that WNT members are capable of activating SUZ12 transcription with varying promoter affinities. Finally, we suggest that SUZ12 is blocking cellular differentiation, as SUZ12 knockdown release differentiation programs in chronic myeloid blastic phase (CML-BP) transformed cell line.

Rhodamine 123 efflux in human subpopulations of hematopoietic stem cells: Comparison between bone marrow, umbilical cord blood and mobilized peripheral blood CD34+ cells

Hematopoietic stem cells (HSC) can be identifiedby the expression of the CD34 molecule. CD34+ cells arefound in bone marrow (BM), umbilical cord blood (UCB)and in mobilized peripheral blood (PB). CD34+ cells expressP-glycoprotein (Pgp), a product of the multidrug resistance(MDR) gene. Pgp activity can be measured by the efflux ofthe dye Rhodamine 123 (Rho 123) and can be blocked byverapamil. Transport activity in HSC suggests that Pgp couldhave a functional role in stem cell differentiation. This studycompared the number of CD34+ cells with Pgp activitymeasured by efflux of Rho 123 in the hematopoietic populationobtained from different sources. Samples were analysed fortheir content of CD34+ cells, and BM had a significantly higheramount of CD34+ cells compared to UCB, mobilized PB andnormal PB. When the frequency of Rholow cells was studiedamong the CD34+ population, an enrichment of cells with Pgpactivity was observed. The frequency in BM was significantlylower than that in UCB and mobilized PB. The low retentionof Rho 123 could be modified by verapamil, indicating thatthe measurements reflected dye efflux due to Pgp activity.Although UCB and mobilized PB had a lower number ofCD34+ cells compared to BM, the total number of CD34+ cellswith Pgp activity was similar in the three tissues. The differentprofiles may indicate the existence of subpopulations of stemcells or different stages of cellular differentiation detected bythe extrusion of the dye Rho 123.(AU)

Hematopoietic stem cell transplantation: a global perspective.

CONTEXT: Hematopoietic stem cell transplantation (HSCT) requires significant infrastructure. Little is known about HSCT use and the factors associated with it on a global level. OBJECTIVES: To determine current use of HSCT to assess differences in its application and to explore associations of macroeconomic factors with transplant rates on a global level. DESIGN, SETTING, AND PATIENTS: Retrospective survey study of patients receiving allogeneic and autologous HSCTs for 2006 collected by 1327 centers in 71 participating countries of the Worldwide Network for Blood and Marrow Transplantation. The regional areas used herein are (1) the Americas (the corresponding World Health Organization regions are North and South America); (2) Asia (Southeast Asia and the Western Pacific Region, which includes Australia and New Zealand); (3) Europe (includes Turkey and Israel); and (4) the Eastern Mediterranean and Africa. MAIN OUTCOME MEASURES: Transplant rates (number of HSCTs per 10 million inhabitants) by indication, donor type, and country; description of main differences in HSCT use; and macroeconomic factors of reporting countries associated with HSCT rates. RESULTS: There were 50 417 first HSCTs; 21 516 allogeneic (43%) and 28 901 autologous (57%). The median HSCT rates varied between regions and countries from 48.5 (range, 2.5-505.4) in the Americas, 184 (range, 0.6-488.5) in Asia, 268.9 (range, 5.7-792.1) in Europe, and 47.7 (range, 2.8-95.3) in the Eastern Mediterranean and Africa. No HSCTs were performed in countries with less than 300,000 inhabitants, smaller than 960 km(2), or having less than US $680 gross national income per capita. Use of allogeneic or autologous HSCT, unrelated or family donors for allogeneic HSCT, and proportions of disease indications varied significantly between countries and regions. In linear regression analyses, government health care expenditures (r(2) = 77.33), HSCT team density (indicates the number of transplant teams per 1 million inhabitants; r(2) = 76.28), human development index (r(2) = 74.36), and gross national income per capita (r(2) = 74.04) showed the highest associations with HSCT rates. CONCLUSION: Hematopoietic stem cell transplantation is used for a broad spectrum of indications worldwide, but most frequently in countries with higher gross national incomes, higher governmental health care expenditures, and higher team densities.

Streptococcal bacteraemia in patients submitted to hematopoietic stem cell transplantation: the role of tooth brushing and use of chlorhexidine.

A retrospective evaluation of 73 consecutive recipients of hematopoietic stem cell transplantation (HSCT) was conducted to investigated the role of oral care and incidence of streptococcal bacteremia in patients submitted to hematopoietic stem cell transplantation. Patients were retrospectively evaluated and divided into group A (GA=38) and group B (GB=35). During hospitalization patients from GA performed oral hygiene daily with extra soft toothbrush and toothpaste besides performing mouth cleaning with an ethanol-free 0.12% chlorhexidine solution tree times a day. In contrast GB patients performed mouth cleaning with extra soft toothbrush and toothpaste, but no chlorhexidine was used. Using the Chi square test it was observed that all patients from GA presented negative blood culture for alpha-hemolytic Streptococcus viridans and Candida albicans and only 1 patient without oral mucositis from GB presented positive blood cultures for Streptococcus intermedius (p=0.48). The results indicate that methodology used for oral care before the HSCT and the practice of tooth brushing during the period were effective in preventing streptococcal bacteremia. Moreover, our data suggest that the mouth cleaning with chlorhexidine during HSCT may be not mandatory.

Similar proteomic profiles of human mesenchymal stromal cells from different donors.

BACKGROUND AIMS: Bone marrow (BM) stromal cells, also referred to as mesenchymal stromal cells (MSC), can be expanded ex vivo and are able to differentiate along multiple lineages, including chondrocytes, osteoblasts and adipocytes. MSC are known to secrete a number of cytokines and regulatory molecules implicated in different aspects of hematopoiesis, and seem to modulate the immune system. MSC appear to be promising candidates for cellular therapy associated with BM transplantation (BMT). METHODS: We compared protein expression profiles of MSC cultures derived from different BM donors using two-dimensional (2-D) gel electrophoresis and matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) tandem mass spectrometry (MS/MS), and compared mixed lymphocyte reaction (MLR) assays in the absence and presence of third-party human (h) MSC derived from different donors during the same culture passage. RESULTS: In a window of observation (pH 4-7, molecular weight 10-220 kDa), about 172 protein spots were obtained in each 2-D gel, corresponding to 84 distinct proteins. A comparative analysis demonstrated a very similar proteomic profile of cells of the first passage derived from different donors, suggesting that these cells have the same expression pattern. Additionally, cells derived from different donors were equally able to inhibit lymphocyte proliferation. CONCLUSIONS: These results encourage the use of third-party MSC in cellular therapies, as cells derived from different individuals seem to have the same proteomic pattern and exhibit functionally similar properties.

Rhodamine 123 efflux in human subpopulations of hematopoietic stem cells: comparison between bone marrow, umbilical cord blood and mobilized peripheral blood CD34+ cells.

Hematopoietic stem cells (HSC) can be identified by the expression of the CD34 molecule. CD34+ cells are found in bone marrow (BM), umbilical cord blood (UCB) and in mobilized peripheral blood (PB). CD34+ cells express P-glycoprotein (Pgp), a product of the multidrug resistance (MDR) gene. Pgp activity can be measured by the efflux of the dye Rhodamine 123 (Rho 123) and can be blocked by verapamil. Transport activity in HSC suggests that Pgp could have a functional role in stem cell differentiation. This study compared the number of CD34+ cells with Pgp activity measured by efflux of Rho 123 in the hematopoietic population obtained from different sources. Samples were analysed for their content of CD34+ cells, and BM had a significantly higher amount of CD34+ cells compared to UCB, mobilized PB and normal PB. When the frequency of Rholow cells was studied among the CD34+ population, an enrichment of cells with Pgp activity was observed. The frequency in BM was significantly lower than that in UCB and mobilized PB. The low retention of Rho 123 could be modified by verapamil, indicating that the measurements reflected dye efflux due to Pgp activity. Although UCB and mobilized PB had a lower number of CD34+ cells compared to BM, the total number of CD34+ cells with Pgp activity was similar in the three tissues. The different profiles may indicate the existence of subpopulations of stem cells or different stages of cellular differentiation detected by the extrusion of the dye Rho 123.

Karyotype abnormalities and their clinical significance in a group of chronic myeloid leukemia patients treated with hematopoietic stem cell transplantation.

CONTEXT AND OBJECTIVE: Following hematopoietic stem cell transplantation (HSCT), karyotyping is a valuable tool for monitoring engraftment and disease status. Few studies have examined the prognostic significance of karyotypes in patients who underwent HSCT for chronic myeloid leukemia (CML). The objective of this study was to evaluate the significance of pretransplantation cytogenetic status in relation to outcomes following HSCT in CML patients. DESIGN AND SETTING: Case series study at Instituto Nacional do Câncer (INCA), Rio de Janeiro, Brazil. METHODS: Cytogenetic analysis was performed by G banding on 39 patients treated with HSCT. RESULTS: Thirty-one patients were in the chronic phase and eight were in the accelerated phase. Prior to HSCT, additional chromosomal abnormalities on the Philadelphia (Ph) chromosome were found in 11 patients. The most frequent additional abnormality was a double Ph, which was observed in four cases. Following HSCT, full chimeras were observed in 31 patients (79.5%). Among these, 23 (82.3%) had presented Ph as the sole abnormality. Mixed chimeras were observed in seven patients, of which three had additional abnormalities. Only one case did not present any cytogenetic response. Five patients presented cytogenetic relapse associated with clinical relapse following HSCT. Twenty-seven patients are still alive and present complete hematological and cytogenetic remission. CONCLUSION: In our study, the presence of additional abnormalities was not associated with worse outcome and relapse risk. Also, no differences in survival rates were observed. Our study supports the view that classical cytogenetic analysis remains an important tool regarding HSCT outcome.

Distribution of HLA-A, -B and -DRB1 antigenic groups and haplotypes from the Brazilian bone marrow donor registry (REDOME).

To improve assistance for patients awaiting a bone marrow transplant from an unrelated donor, it is important to genetically characterize the Brazilian volunteer bone marrow donors registry (REDOME). Our objective was to describe the antigenic groups and haplotype frequencies of HLA-A, HLA-B and HLA-DRB1 in the five regions of Brazil and by self-reported ethnicity groups using the REDOME data. Our study included 3,038,286 individuals. HLA antigenic groups and haplotype frequencies were estimated using an Expectation-Maximization (EM) algorithm. All described HLA-A*, HLA-B* and HLA-DRB1* groups were identified in this study. A*02 (25.9%), B*35 (11.8%) and DRB1*13 (13.4%) are the most frequent antigenic groups in REDOME, and the A*01-B*08-DRB1*03 haplotype is the most frequent in the registry. The antigenic group and haplotype frequency data obtained in this study could be helpful for national donor recruitment strategies across the country.

Validation of the single-platform ISHAGE protocol for enumeration of CD34+ hematopoietic stem cells in umbilical cord blood in a Brazilian center

Abstract Background This study aims to validate the single-platform method for enumeration of CD34+ cells, by comparing the performance of two different commercial kits, as well as to evaluate the efficiency of the AccuriTM C6 cytometer in providing direct counts of absolute cell numbers. Method We evaluated 20 samples from umbilical cord blood (UCB), comparing the two different methodologies for enumeration of CD34+ cells: single and dual-platform. For the assessment of the single-platform, Procount and SCE kits were used, both of which use fluorescent beads as a counting reference to obtain absolute CD34+ cells numbers. Moreover, after the acquisition of samples in flow cytometer AccuriTM C6, following the protocol established for each kit, the number of CD34+ cells was recalculated, considering the cell count provided by the AccuriTM C6. Main Results In our analysis, the results showed a strong correlation between the number of CD34+ cells/μL (r2 = 0.77) when comparing the SCE kit and the current dual-platform method. On the other hand, the comparison between Procount kit and dual-platform results showed a moderate correlation for the number of CD34+/μL cells (r2 = 0.64). Conclusion Our results showed that the AccuriTM C6 flow cytometer can be used safely, applying both the dual and single platform analysis strategy. Considering the ISHAGE protocol-based single-platform approach, as the most appropriate methodology for CD34+ cells enumeration, our results demonstrated that the SCE kit has great potential for national standardization of UCB samples analysis methodology.

One million haemopoietic stem-cell transplants: a retrospective observational study.

BACKGROUND: The transplantation of cells, tissues, and organs has been recognised by WHO as an important medical task for its member states; however, information about how to best organise transplantation is scarce. We aimed to document the activity worldwide from the beginning of transplantation and search for region adapted indications and associations between transplant rates and macroeconomics. METHODS: Between Jan 1, 2006, and Dec 31, 2014, the Worldwide Network for Blood and Marrow Transplantation collected data for the evolution of haemopoietic stem-cell transplantation (HSCT) activity and volunteer donors in the 194 WHO member states. FINDINGS: 953,651 HSCTs (553,350 [58%] autologous and 400,301 [42%] allogeneic) were reported by 1516 transplant centres from 75 countries. No transplants were done in countries with fewer than 300,000 inhabitants, a surface area less than 700 km(2), and a gross national income per person of US$1260 or lower. Use of HSCT increased from the first transplant in 1957 to almost 10,000 by 1985. We recorded a cumulative total of about 100,000 transplants by 1995, and an estimated 1 million by December, 2012. Unrelated donor registries contributed 22·3 million typed volunteer donors and 645,646 cord blood products by 2012. Numbers of allogeneic HSCTs increased in the past 35 years with no signs of saturation (R(2)=0·989). Transplant rates were higher in countries with more resources, more transplant teams, and an unrelated donor infrastructure. INTERPRETATION: Our findings show achievements and high unmet needs and give guidance for decisions; to grant access for patients, to provide a donor infrastructure, and to limit overuse by defining risk and region adapted indications for HSCT as an efficient and cost-effective approach for life-threatening, potentially curable diseases. FUNDING: Funding for this study was indirectly provided by support of the WBMT.

Less graft-versus-host disease after rabbit antithymocyte globulin conditioning in unrelated bone marrow transplantation for leukemia and myelodysplasia: comparison with matched related bone marrow transplantation.

One of the major drawbacks for unrelated donor (UD) bone marrow transplantation (BMT) is graft-versus-host disease (GVHD). Despite results from randomized trials, antithymocyte globulin (ATG) is not routinely included for GVHD prophylaxis in UD BMT by many centers. One of ways to demonstrate the usefulness of rabbit ATG in UD BMT is to evaluate how its results approximate to those observed in matched related (MRD) BMT. Therefore, we compared the outcomes between UD BMT with rabbit ATG (Thymoglobulin) for GVHD prophylaxis (n = 25) and MRD BMT (n = 91) for leukemia and myelodysplasia. All but one patient received a myeloablative conditioning regimen. Grades II-IV acute GVHD were similar (39.5% vs. 36%, p = 0.83); however, MRD BMT recipients developed more moderate-severe chronic GVHD (36.5% vs. 8.6%, p = 0.01) and GVHD-related deaths (32.5% vs. 5.6%, p = 0.04). UD BMT independently protected against chronic GVHD (hazard ratio 0.23, p = 0.04). The 6-month transplant-related mortality, 1-year relapse incidence, and 5-year survival rates were similar between patients with non-advanced disease in the MRD and UD BMT groups, 13.8% vs. 16.6% (p = 0.50), 20.8% vs. 16.6% (p = 0.37), and 57% vs. 50% (p = 0.67), respectively. Stable full donor chimerism was equally achieved (71.3% vs. 71.4%, p = 1). Incorporation of rabbit ATG in UD BMT promotes less GVHD, without jeopardizing chimerism evolution, and may attain similar survival outcomes as MRD BMT for leukemia and myelodysplasia especially in patients without advanced disease.