Stepwise emergence of the neuronal gene expression program in early animal evolution.

The assembly of the neuronal and other major cell type programs occurred early in animal evolution. We can reconstruct this process by studying non-bilaterians like placozoans. These small disc-shaped animals not only have nine morphologically described cell types and no neurons but also show coordinated behaviors triggered by peptide-secreting cells. We investigated possible neuronal affinities of these peptidergic cells using phylogenetics, chromatin profiling, and comparative single-cell genomics in four placozoans. We found conserved cell type expression programs across placozoans, including populations of transdifferentiating and cycling cells, suggestive of active cell type homeostasis. We also uncovered fourteen peptidergic cell types expressing neuronal-associated components like the pre-synaptic scaffold that derive from progenitor cells with neurogenesis signatures. In contrast, earlier-branching animals like sponges and ctenophores lacked this conserved expression. Our findings indicate that key neuronal developmental and effector gene modules evolved before the advent of cnidarian/bilaterian neurons in the context of paracrine cell signaling.

Collective and Diverted Total Synthesis of the Strasseriolides: A Family of Macrolides Endowed with Potent Antiplasmodial and AntitrypanosomalActivity.

The strasseriolide macrolides show promising in vitro and in vivo activities against P. falciparum and T. cruzi, the parasites causing malaria and Chagas disease, respectively. However, the as yet poor understanding of structure/activity relationships and the fact that one family member proved systemically toxic for unknown reasons render a more detailed assessment of these potential lead compounds difficult. To help overcome these issues, a collective total synthesis was devised. The key steps consisted of a ring closing alkyne metathesis (RCAM) reaction to forge a common macrocyclic intermediate followed by a hydroxy-directed ruthenium catalyzed trans-hydrostannation of the propargyl alcohol site thus formed. The resulting alkenyltin derivative served as the central node of the synthesis blueprint, which could be elaborated into the natural products themselves as well as into a set of non-natural analogues according to the concept of diverted total synthesis. The recorded biological data confirmed the potency of the compounds and showed the lack of noticeable cytotoxicity. The "northern" allylic alcohol subunit was recognized as an integral part of the pharmacophore, yet it provides opportunities for chemical modification.

An epitope-based approach of HLA-matched platelets for transfusion: a noninferiority crossover randomized trial.

Platelet transfusion refractoriness results in adverse outcomes and increased health care costs. Managing refractoriness resulting from HLA alloimmunization necessitates the use of HLA antigen-matched platelets but requires a large platelet donor pool and does not guarantee full matching. We report the first randomized, double-blind, noninferiority, crossover trial comparing HLA epitope-matched (HEM) platelets with HLA standard antigen-matched (HSM) platelet transfusions. Alloimmunized, platelet-refractory, thrombocytopenic patients with aplastic anemia, myelodysplastic syndrome, or acute myeloid leukemia were eligible. HEM platelets were selected using HLAMatchMaker epitope (specifically eplet) matching. Patients received up to 8 prophylactic HEM and HSM transfusions provided in random order. The primary outcome was 1-hour posttransfusion platelet count increment (PCI). Forty-nine patients were randomized at 14 UK hospitals. For intention to treat, numbers of evaluable transfusions were 107 and 112 for HEM and HSM methods, respectively. Unadjusted mean PCIs for HEM and HSM methods were 23.9 (standard deviation [SD], 15) and 23.5 (SD, 14.1), respectively (adjusted mean difference, -0.1; 95% confidence interval [CI], -2.9 to 2.8). Because the lower limit of the 95% CI was not greater than the predefined noninferiority limit, the HEM approach was declared noninferior to the HSM approach. There were no differences in secondary outcomes of platelet counts, transfusion requirements, and bleeding events. Adequate 1-hour PCI was more frequently observed, with a mean number of 3.2 epitope mismatches, compared with 5.5 epitope mismatches for inadequate 1-hour increments. For every additional epitope mismatch, the likelihood of an adequate PCI decreased by 15%. Epitope-matched platelets should be considered to support HLA alloimmunized patients. This trial was registered at www.isrctn.com as #ISRCTN23996532.

Hepatitis C eradication improves cognitive function in patients with or without cirrhosis: A prospective real-life study.

BACKGROUND AND PURPOSE: Hepatitis C virus (HCV) infection is associated with neuropsychiatric disturbances that impact on functioning and health-related quality of life (HRQoL). Reversibility at different liver disease stages is unknown, particularly in cirrhosis. We aimed to evaluate cognition, functioning, and HRQoL following HCV eradication at different liver disease stages. METHODS: A random sample (n = 152) of consecutive patients treated with direct-acting antiviral agents (DAAs) between April 2015 and March 2017 were included. A comprehensive neuropsychological assessment, functioning and HRQoL questionnaires were applied at baseline, and 12 and 48 weeks after the end of antivirals. RESULTS: One-hundred thirty-five patients who achieved virological response completed the follow-up, of whom 44 had cirrhosis (27% decompensated). Twenty-one percent had cognitive impairment before starting DAAs (34.1% cirrhotic vs. 14.4% noncirrhotic, p < 0.011). Viral eradication was associated with a decrease in cognitive impairment to 23% of cirrhotic and 6% of noncirrhotic patients (p < 0.05). Interestingly, older patients (B = 0.11, 95% confidence interval [CI] = 0.03-0.19) with baseline cognitive impairment (B = 3.58, 95% CI = 1.54-5.62) were those with higher cognitive benefit, regardless of liver disease. Persistent cognitive impairment was associated with having higher cardiovascular risk, cirrhosis, lower education, and higher anxiety and depression scores. Functioning and HRQoL also improved after eradication but remained worse in the cirrhotic group. CONCLUSIONS: Viral eradication decreases the prevalence of cognitive impairment and improves functioning and HRQoL. Patients with lower brain reserve (older patients) and baseline cognitive impairment may benefit the most. Identification and treatment of HCV patients through screening programs may reduce the burden of cognitive disturbances beyond the prevention of liver disease progression.

Huntington's disease brain-derived small RNAs recapitulate associated neuropathology in mice.

Progressive motor alterations and selective death of striatal medium spiny neurons (MSNs) are key pathological hallmarks of Huntington's disease (HD), a neurodegenerative condition caused by a CAG trinucleotide repeat expansion in the coding region of the huntingtin (HTT) gene. Most research has focused on the pathogenic effects of the resultant protein product(s); however, growing evidence indicates that expanded CAG repeats within mutant HTT mRNA and derived small CAG repeat RNAs (sCAG) participate in HD pathophysiology. The individual contribution of protein versus RNA toxicity to HD pathophysiology remains largely uncharacterized and the role of other classes of small RNAs (sRNA) that are strongly perturbed in HD is uncertain. Here, we demonstrate that sRNA produced in the putamen of HD patients (HD-sRNA-PT) are sufficient to induce HD pathology in vivo. Mice injected with HD-sRNA-PT show motor abnormalities, decreased levels of striatal HD-related proteins, disruption of the indirect pathway, and strong transcriptional abnormalities, paralleling human HD pathology. Importantly, we show that the specific blockage of sCAG mitigates HD-sRNA-PT neurotoxicity only to a limited extent. This observation prompted us to identify other sRNA species enriched in HD putamen with neurotoxic potential. We detected high levels of tRNA fragments (tRFs) in HD putamen, and we validated the neurotoxic potential of an Alanine derived tRF in vitro. These results highlight that HD-sRNA-PT are neurotoxic, and suggest that multiple sRNA species contribute to striatal dysfunction and general transcriptomic changes, favoring therapeutic strategies based on the blockage of sRNA-mediated toxicity.

HCV eradication in recurrent hepatitis C after liver transplantation normalizes enhanced endothelial activation.

The increased risk of cardiovascular disease (CVD) conferred by hepatitis C virus (HCV) is especially relevant after liver transplantation (LT), but its mechanism is still not well defined. This study aimed to evaluate the influence of HCV eradication in inflammatory and endothelial activation markers after LT. We evaluated inflammatory (TNF-alfa, IL-6, IL-8, and MCP-1) and endothelial activation (E-selectin, ICAM-1, VCAM-1, and MMP-9) markers before and after eradication in 45 LT recipients with HCV infection (LT+/HCV+) and 44 non-transplanted HCV-infected patients (LT-/HCV+). We also considered an additional group of 40 LT recipients without HCV infection (LT+/HCV-). LT+/HCV+ patients presented a higher endothelial activation status before eradication compared with LT+/HCV- patients. However, levels of E-selectin, ICAM-1, VCAM-1, and MMP-9 were comparable between LT+/HCV+ and LT-/HCV+ patients before eradication. HCV eradication decreased ICAM-1 (5466.55 pg/ml vs. 3354.88 pg/ml, P < 0.001) and VCAM-1 (10456.52 pg/ml vs. 6658.85 pg/ml, P < 0.001) levels in LT+/HCV+ and LT-/HCV+ patients. Remarkably, HCV eradication restored levels of endothelial activation markers of LT+/HCV+ patients compared with that of LT+/HCV- patients. HCV plays a major role in endothelial dysfunction after LT. Furthermore, HCV eradication restores endothelial activation despite the exposure to immunosuppressive therapy.

Meningitis, urinary tract, and bloodstream infections in very low birth weight infants enrolled in a heart rate characteristics monitoring trial.

BACKGROUND: Displaying heart rate characteristic (HRC) scores was associated with lower sepsis-associated mortality in very low birth weight (VLBW) infants in a multicenter randomized controlled trial (HeRO trial). The aim of this study was to test whether HRC indices rise before diagnosis of urinary tract infection (UTI) or meningitis, with and without concomitant BSI. METHODS: Blood, urine, and cerebrospinal fluid (CSF) culture data after 3 days of age and within 120 days of study enrollment were analyzed from 2989 VLBW infants. The HRC index was analyzed 12 h prior to positive cultures compared to 36 h prior, using paired signed-rank tests. RESULTS: UTI, meningitis, and BSI were diagnosed in 10%, 2%, and 24% of infants, respectively. The mean hourly HRC index was significantly higher 12 h prior to diagnosis of UTI and BSI compared to 36 h prior (UTI 2.07 versus 1.81; BSI 2.62 versus 2.25, both p < 0.0001). The baseline HRC index was higher for meningitis, compared to UTI or BSI, but without a statistically significant rise in the day prior to meningitis diagnosis. CONCLUSIONS: In a large cohort of VLBW infants enrolled in the HeRO trial, the HRC index increased in the 24-h period prior to diagnosis of UTI and BSI but not meningitis.

Impact of Human Leucocyte Antigen epitope matched platelet transfusions in alloimmunised aplastic anaemia patients.

AIMS/OBJECTIVES: To explore the impact of Human Leucocyte Antigen (HLA)-A and B epitope-matched platelets on the outcome of platelet transfusions in alloimmunised patients with aplastic anaemia (AA). The relevance of HLA-C epitope mismatches was also investigated. BACKGROUND: Patients who become immunologically refractory (IR) to random platelet transfusions can experience an adequate rise in platelet count through the provision of HLA-compatible platelets using an antigen-matching algorithm. This approach has been shown to be effective in patients with a low calculated reaction frequency, but it is not always successful in highly sensitised patients. The use of HLA epitopes-selected platelets has been suggested as an alternative to the antigen matching approach. METHODS: The effect of HLA epitope matching (both Eplets and Triplets) on the outcome of platelet transfusion was analysed in 37 highly immunised AA patients previously transfused with HLA-A and B antigen-matched platelets. Epitope matching was determined using the HLAMatchmaker programme. The outcome of the transfusions was assessed by the platelet count increments (PCIs) obtained 1 and 24 hours post-transfusions. RESULTS: HLA-A and B epitope matching was equivalent to HLA antigen matching in raising platelet counts. There was no significant difference in PCI when HLA-C epitope mismatches were considered. In addition, transfusions with fewer than two antigen mismatches resulted in significantly higher PCIs compared to transfusions with more than two antigen mismatches. CONCLUSIONS: HLA epitope-matched platelet provision may represent a clinically effective transfusion strategy for patients IR to random platelet transfusions. Further prospective studies are required.

Vitamin D status among preterm infants with cholestasis and metabolic bone disease.

BACKGROUND: Metabolic bone disease of prematurity (MBD) is a common problem among preterm infants. Our previous study identified cholestasis as an important risk factor for the development of MBD. We conducted this study to determine the vitamin D status in preterm infants with MBD and cholestasis. METHODS: We retrospectively reviewed medical record of preterm infants evaluated in NICU at Holtz Children's/Jackson Memorial Hospital between June 2014 and May 2016. Demographic, biochemical data, and vitamin D intake were collected and analyzed. RESULTS: We identified 58 preterm infants (median gestational age 25 weeks) with MBD during this period. Twenty five infants also developed cholestasis. Median serum 25-hydroxyvitamin D level at the time of diagnosis of MBD was similar in cholestasis (C), (29.1 ng/ml, IQR 24.4-33.5), and non-cholestasis (NC), (28.7 ng/ml, IQR 22.7-34.6), group (p = 0.41). At the second measurement, average 6 weeks after the first measurement; median serum 25-hydroxyvitamin D level was lower (p = 0.02) in the C group (31.2 ng/ml, IQR 23.0-38.8) than in the NC group (36.5 ng/ml, IQR 28-45). However, the actual percentage of infants with vitamin D deficiency was similar in both the groups. CONCLUSION: Most preterm infants with cholestasis and MBD had normal vitamin D status.

Mesenchymal stromal cells as treatment or prophylaxis for acute or chronic graft-versus-host disease in haematopoietic stem cell transplant (HSCT) recipients with a haematological condition.

BACKGROUND: Recipients of allogeneic haematopoietic stem cell transplants (HSCT) can develop acute or chronic, or both forms of graft-versus-host disease (a/cGvHD), whereby immune cells of the donor attack host tissues. Steroids are the primary treatment, but patients with severe, refractory disease have limited options and a poor prognosis. Mesenchymal stromal cells (MSCs) exhibit immunosuppressive properties and are being tested in clinical trials for their safety and efficacy in treating many immune-mediated disorders. GvHD is one of the first areas in which MSCs were clinically applied, and it is important that the accumulating evidence is systematically reviewed to assess whether their use is favoured. OBJECTIVES: To determine the evidence for the safety and efficacy of MSCs for treating immune-mediated inflammation post-transplantation of haematopoietic stem cells. SEARCH METHODS: We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL, the Cochrane Library 2018, Issue 12), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), Web of Science: Conference Proceedings Citation Index-Science (CPCI-S) (from 1990) and ongoing trial databases to 6 December 2018. No constraints were placed on language or publication status. SELECTION CRITERIA: We included RCTs of participants with a haematological condition who have undergone an HSCT as treatment for their condition and were randomised to MSCs (intervention arm) or no MSCs (comparator arm), to prevent or treat GvHD. We also included RCTs which compared different doses of MSCs or MSCs of different sources (e.g. bone marrow versus cord). We included MSCs co-transplanted with haematopoietic stem cells as well as MSCs administered post-transplantation of haematopoietic stem cells. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane.We employed a random-effects model for all analyses due to expected clinical heterogeneity arising from differences in participant characteristics and interventions. MAIN RESULTS: We identified 12 completed RCTs (879 participants), and 13 ongoing trials (1532 enrolled participants planned). Of 12 completed trials, 10 compared MSCs versus no MSCs and two compared different doses of MSCs. One trial was in people with thalassaemia major, the remaining trials were for haematological malignancies. Seven trials administered MSCs to prevent GvHD, whereas five trials gave MSCs to treat GvHD.In the comparison of MSCs with no MSCs, cells were administered at a dose of between 105 and 107 cells/kg in either a single dose (six trials) or in multiple doses (four trials) over a period of three days to four months. The dose-comparison trials compared 2 x 106 cells/kg with 8 x 106 cells/kg in two infusions, or 1 x 106 cells/kg with 3 x 106 cells/kg in a single infusion.The median duration of follow-up in seven trials which administered MSCs prophylactically ranged from 10 to 60 months. In three trials of MSCs as treatment for aGvHD, participants were followed up for 90 or 100 days. In two trials of MSCs as treatment for cGvHD, the mean duration of follow-up was 13.4 months (MSC group) and 23.6 months (control group) in one trial, and 56 weeks in the second trial. Five trials included adults only, six trials included adults and children, and one trial included children only. In eight trials which reported the gender distribution, the percentage of females ranged from 20% to 59% (median 35.8%).The overall quality of the included studies was low: randomisation methods were poorly reported and several of the included studies were subject to a high risk of performance bias and reporting bias. One trial which started in 2008 has not been published and the progress of this trial in unknown, leading to potential publication bias. The quality of evidence was therefore low or very low for all outcomes due to a high risk of bias as well as imprecision due to the low number of overall participants, and in some cases evidence based on a single study. We found that MSCs may make little or no difference in the risk of all-cause mortality in either prophylactic trials (HR 0.85, 95% CI 0.50 to 1.42; participants = 301; studies = 5; I2 = 34% ; low-quality evidence) or therapeutic trials (HR 1.12, 95% CI 0.80 to 1.56; participants = 244; studies = 1; very low-quality evidence), and no difference in the risk of relapse of malignant disease (prophylactic trials: RR 1.08, 95% CI 0.73 to 1.59; participants = 323; studies = 6; I2 = 0%; low-quality evidence) compared with no MSCs. MSCs were well-tolerated, no infusion-related toxicity or ectopic tissue formation was reported. No study reported health-related quality of life. In prophylactic trials, MSCs may reduce the risk of chronic GvHD (RR 0.66, 95% CI 0.49 to 0.89; participants = 283; studies = 6; I2 = 0%; low-quality evidence). This means that only 310 (95% CI 230 to 418) in every 1000 patients in the MSC arm are expected to develop chronic GvHD compared to 469 in the control arm. However, MSCs may make little or no difference to the risk of aGvHD (RR 0.86, 95% CI 0.63 to 1.17; participants = 247; studies = 6; I2 = 0%; low-quality evidence). In GvHD therapeutic trials, we are very uncertain whether MSCs improve complete response of either aGvHD (RR 1.16, 95% CI 0.79 to 1.70, participants = 260, studies = 1; very low-quality evidence) or cGvHD (RR 5.00, 95%CI 0.75 to 33.21, participants = 40, studies = 1; very low-quality evidence).In two trials which compared different doses of MSCs, we found no evidence of any differences in outcomes. AUTHORS' CONCLUSIONS: MSCs are an area of intense research activity, and an increasing number of trials have been undertaken or are planned. Despite a number of reports of positive outcomes from the use of MSCs for treating acute GvHD, the evidence to date from RCTs has not supported the conclusion that they are an effective therapy. There is low-quality evidence that MSCs may reduce the risk of cGvHD. New trial evidence will be incorporated into future updates of this review, which may better establish a role for MSCs in the prevention or treatment of GvHD.

Evaluation of Ion Torrent sequencing technology for rapid clinical human leucocyte antigen typing.

The development of techniques to define the human leucocyte antigen (HLA) region has proven to be challenging due to its high level of polymorphism. Within a clinical laboratory, a technique for high-resolution HLA typing, which is rapid and cost effective is essential. NGS has provided a rapid, high-resolution HLA typing solution, which has reduced the number of HLA ambiguities seen with other typing methods. In this study, the One Lambda NXType NGS kit was tested on the Ion Torrent PGM platform. A total of 362 registry donors from four ethnic populations (Europeans, South Asians, Africans and Chinese) were NGS HLA typed across 9-loci (HLA-A, -B, -C, -DRB1,-DRB345 -DQB1 and -DPB1). Concordance rates of 91%-98% were obtained (for HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1) when compared to historical PCR-SSO HLA types, and the identification of uncommon alleles such as A*24:07:01 and C*04:82 were observed. A turnaround time of four days was achieved for typing 44 samples. However, some limitations were observed; primer locations did not allow all ambiguities to be resolved for HLA Class II where Exon I and IV amplification are needed (HLA-DRB1*04:07:01/04:92, HLA-DRB1*09:01:02/*09:21 and HLA-DRB1*12:01:01/*12:10). This study has demonstrated high-resolution typing by NGS can be achieved in an acceptable turnaround time for a clinical laboratory; however, the Ion Torrent workflow has some technical limitations that should be addressed.

Umbilical Cord Blood Cytomegalovirus Serostatus Does Not Have an Impact on Outcomes of Umbilical Cord Blood Transplantation for Acute Leukemia.

Several studies have reported an impact of adult hematopoietic stem cell donor cytomegalovirus (CMV) serostatus on allogeneic hematopoietic cell transplantation outcomes. Limited data, however, are available on the impact of cord blood unit (CBU) CMV serostatus on allogeneic umbilical cord blood transplantation (UCBT) outcomes. We analyzed, retrospectively, the impact of CBU CMV serostatus on relapse incidence (RI) and 2-year nonrelapse mortality (NRM) of single-unit CBU transplantation for acute leukemia. Data from 1177 de novo acute leukemia pediatric and adult patients transplanted within European Group for Blood and Marrow Transplantation centers between 2000 and 2012 were analyzed. CBUs were provided by the European Cord Blood Banks. The median follow-up time for live patients was 59.9 months. The recipients of CMV-seropositive and -seronegative CBUs showed a comparable RI (33% versus 35%, respectively, P = .6) and 2-year cumulative incidence of NRM (31% versus 32%, respectively, P = .5). We conclude that CBU CMV serostatus did not influence RI and NRM in de novo acute leukemia patients after allo-UCBT and should not be included as a criteria for cord blood choice.

Simultaneous human platelet antigen genotyping and detection of novel single nucleotide polymorphisms by targeted next-generation sequencing.

BACKGROUND: Twenty-nine human platelet antigen systems have been described to date, but the majority of current genotyping methods are restricted to the identification of those most commonly associated with alloantibody production in a clinical context. This can result in a protracted investigation if causative human platelet antigens are rare or novel. A targeted next-generation sequencing approach was designed to detect all known human platelet antigens with the additional capability of identifying novel mutations in the encoding genes. STUDY DESIGN AND METHODS: A targeted enrichment, high-sensitivity HaloPlex assay was designed to sequence all exons and flanking regions of the six genes known to encode human platelet antigens. Indexed DNA libraries were prepared from 47 previously human platelet antigen-genotyped samples and subsequently combined into one of three pools for sequencing on an Illumina MiSeq platform. The generated FASTQ files were aligned and scrutinized for each human platelet antigen polymorphism using SureCall data analysis software. RESULTS: Forty-six samples were successfully genotyped for human platelet antigens 1 through 29bw, with an average per base coverage depth of 1144. Concordance with historical human platelet antigen genotypes was 100%. A putative novel mutation in Exon 10 of the integrin ß-3 (ITGB3) gene from an unsolved case of fetal neonatal alloimmune thrombocytopenia was also detected. CONCLUSION: A next-generation sequencing-based method that can accurately define all known human platelet antigen polymorphisms was developed. With the ability to sequence up to 96 samples simultaneously, our HaloPlex design could be used for high-throughput human platelet antigen genotyping. This method is also applicable for investigating fetal neonatal alloimmune thrombocytopenia when rare or novel human platelet antigens are suspected.

Growth Outcomes of Preterm Infants Exposed to Different Oxygen Saturation Target Ranges from Birth.

OBJECTIVE: To test whether infants randomized to a lower oxygen saturation (peripheral capillary oxygen saturation [SpO2]) target range while on supplemental oxygen from birth will have better growth velocity from birth to 36 weeks postmenstrual age (PMA) and less growth failure at 36 weeks PMA and 18-22 months corrected age. STUDY DESIGN: We evaluated a subgroup of 810 preterm infants from the Surfactant, Positive Pressure, and Oxygenation Randomized Trial, randomized at birth to lower (85%-89%, n = 402, PMA 26 ± 1 weeks, birth weight 839 ± 186 g) or higher (91%-95%, n = 408, PMA 26 ± 1 weeks, birth weight 840 ± 191 g) SpO2 target ranges. Anthropometric measures were obtained at birth, postnatal days 7, 14, 21, and 28; then at 32 and 36 weeks PMA; and 18-22 months corrected age. Growth velocities were estimated with the exponential method and analyzed with linear mixed models. Poor growth outcome, defined as weight <10th percentile at 36 weeks PMA and 18-22 months corrected age, was compared across the 2 treatment groups by the use of robust Poisson regression. RESULTS: Growth outcomes including growth at 36 weeks PMA and 18-22 months corrected age, as well as growth velocity were similar in the lower and higher SpO2 target groups. CONCLUSION: Targeting different oxygen saturation ranges between 85% and 95% from birth did not impact growth velocity or reduce growth failure in preterm infants.

Impact of cord blood banking technologies on clinical outcome: a Eurocord/Cord Blood Committee (CTIWP), European Society for Blood and Marrow Transplantation and NetCord retrospective analysis.

BACKGROUND: Techniques for banking cord blood units (CBUs) as source for hematopoietic stem cell transplantation have been developed over the past 20 years, aimed to improve laboratory efficiency without altering the biologic properties of the graft. A large-scale, registry-based assessment of the impact of the banking variables on the clinical outcome is currently missing. STUDY DESIGN AND METHODS: A total of 677 single cord blood transplants (CBTs) carried out for acute leukemia in complete remission in centers affiliated with the European Society for Blood and Marrow Transplantation were selected. An extensive set of data concerning CBU banking were collected and correlations with clinical outcome were assessed. Clinical endpoints were transplant-related mortality, engraftment, and graft-versus-host disease (GVHD). RESULTS: The median time between collection and CBT was 4.1 years (range, 0.2-16.3 years). Volume reduction (VR) of CBUs before freezing was performed in 59.2% of available reports; in half of these the frozen volume was less than 30 mL. Cumulative incidences of neutrophil engraftment on Day 60, 100-day acute GVHD (II-IV), and 4-year chronic GVHD were 87, 29, and 21 ± 2%. The cumulative incidence of nonrelapse mortality (NRM) at 100 days and 4-year NRM were, respectively, 16 ± 2 and 30 ± 2%. Neither the variables related to banking procedures nor the interval between collection and CBT influenced the clinical outcome. CONCLUSION: These findings indicate a satisfactory validation of the techniques associated with CBU VR across the banks. Cell viability assessment varied among the banks, suggesting that efforts to improve the standardization of CBU quality controls are needed.

Platelet refractoriness--practical approaches and ongoing dilemmas in patient management.

Platelet refractoriness can represent a significant clinical problem that complicates the provision of platelet transfusions, is associated with adverse clinical outcomes and increases health care costs. Although it is most frequently due to non-immune platelet consumption, immunological factors are also often involved. Human leucocyte antigen (HLA) alloimmunization is the most important immune cause. Despite the fact that systematic reviews of the clinical studies evaluating different techniques for selecting HLA compatible platelets have not been powered to demonstrate improved clinical outcomes, platelet refractoriness is currently managed by the provision of HLA-matched or cross matched platelets. This review will address a practical approach to the diagnosis and management of platelet refractoriness while highlighting on-going dilemmas and knowledge gaps.

Enhancement of the immunoregulatory potency of mesenchymal stromal cells by treatment with immunosuppressive drugs.

BACKGROUND AIMS: Multipotent mesenchymal stromal cells (MSCs) are distinguished by their ability to differentiate into a number of stromal derivatives of interest for regenerative medicine, but they also have immunoregulatory properties that are being tested in a number of clinical settings. METHODS: We show that brief incubations with rapamycin, everolimus, FK506 or cyclosporine A increase the immunosuppressive potency of MSCs and other cell types. RESULTS: The treated MSCs are up to 5-fold more potent at inhibiting the induced proliferation of T lymphocytes in vitro. We show that this effect probably is due to adsorption of the drug by the MSCs during pre-treatment, with subsequent diffusion into co-cultures at concentrations sufficient to inhibit T-cell proliferation. MSCs contain measurable amounts of rapamycin after a 15-min exposure, and the potentiating effect is blocked by a neutralizing antibody to the drug. With the use of a pre-clinical model of acute graft-versus-host disease, we demonstrate that a low dose of rapamycin-treated but not untreated umbilical cord-derived MSCs significantly inhibit the onset of disease. CONCLUSIONS: The use of treated MSCs may achieve clinical end points not reached with untreated MSCs and allow for infusion of fewer cells to reduce costs and minimize potential side effects.

A multicenter validation of recombinant ß3 integrin-coupled beads to detect human platelet antigen-1 alloantibodies in 498 cases of fetomaternal alloimmune thrombocytopenia.

BACKGROUND: Fetomaternal alloimmune thrombocytopenia (FMAIT) is caused by human platelet (PLT) antigen (HPA) incompatibility. Beads coupled with recombinant ß3 integrins, displaying the biallelic HPA-1 epitopes (rHPA-1), have been shown to detect HPA-1a alloantibodies implicated in FMAIT. This report describes a multicenter validation of the beads using the results of well-characterized samples to define the optimum parameters for analysis of a large cohort of 498 clinical samples. STUDY DESIGN AND METHODS: Fifty-one blinded quality assurance (QA) samples were tested by six laboratories to standardize the rHPA-1 bead assay and to develop an algorithm for sample classification. Five laboratories retrieved samples from 498 independent FMAIT cases, previously tested by the monoclonal antibody-specific immobilization of PLT antigens (MAIPA) assay, from their local archives for testing with the rHPA-1 beads. The results were evaluated using a mathematical algorithm developed to classify the samples. RESULTS: The QA samples gave a mean concordance of 94% between the bead and MAIPA assays, while 97% concordance was observed with the FMAIT samples. Of the 15 discrepant samples, seven were positive by the beads but negative by MAIPA, while the contrary was observed for eight samples. Overall, the bead assay achieved 98% sensitivity for HPA-1a antibody detection in FMAIT and 98.7% specificity compared to the local MAIPA. CONCLUSION: The rHPA-1 bead assay is a rapid 3-hour assay for the sensitive detection of HPA-1 antibodies. Its ease of use would enable prompt detection of maternal HPA-1a antibodies in suspected FMAIT cases, which is important supportive evidence for treatment by transfusion with HPA-1b1b PLTs.

Engraftment kinetics and graft failure after single umbilical cord blood transplantation using a myeloablative conditioning regimen.

Umbilical cord blood transplant recipients are exposed to an increased risk of graft failure, a complication leading to a higher rate of transplant-related mortality. The decision and timing to offer a second transplant after graft failure is challenging. With the aim of addressing this issue, we analyzed engraftment kinetics and outcomes of 1268 patients (73% children) with acute leukemia (64% acute lymphoblastic leukemia, 36% acute myeloid leukemia) in remission who underwent single-unit umbilical cord blood transplantation after a myeloablative conditioning regimen. The median follow-up was 31 months. The overall survival rate at 3 years was 47%; the 100-day cumulative incidence of transplant-related mortality was 16%. Longer time to engraftment was associated with increased transplant-related mortality and shorter overall survival. The cumulative incidence of neutrophil engraftment at day 60 was 86%, while the median time to achieve engraftment was 24 days. Probability density analysis showed that the likelihood of engraftment after umbilical cord blood transplantation increased after day 10, peaked on day 21 and slowly decreased to 21% by day 31. Beyond day 31, the probability of engraftment dropped rapidly, and the residual probability of engrafting after day 42 was 5%. Graft failure was reported in 166 patients, and 66 of them received a second graft (allogeneic, n=45). Rescue actions, such as the search for another graft, should be considered starting after day 21. A diagnosis of graft failure can be established in patients who have not achieved neutrophil recovery by day 42. Moreover, subsequent transplants should not be postponed after day 42.

Twin infant with lymphatic dysplasia diagnosed with Noonan syndrome by molecular genetic testing.

Noonan Syndrome is an autosomal dominant disorder characterized by short stature, congenital heart defects, developmental delay, dysmorphic facial features and occasional lymphatic dysplasias. The features of Noonan Syndrome change with age and have variable expression. The diagnosis has historically been based on clinical grounds. We describe a child that was born with congenital refractory chylothorax and subcutaneous edema suspected to be secondary to pulmonary lymphangiectasis. The infant died of respiratory failure and anasarca at 80 days. The autopsy confirmed lymphatic dysplasia in lungs and mesentery. The baby had no dysmorphic facial features and was diagnosed postmortem with Noonan syndrome by genomic DNA sequence analysis as he had a heterozygous mutation for G503R in the PTPN11 gene.