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Neutrophils and their granular enzymes such as neutrophil elastase (NE) and myeloperoxidase (MPO) play important roles in inflammatory diseases, and might be utilized as biomarkers for disease severity and progression. The aim of this study was to determine reference intervals for NE and MPO activity in healthy volunteers comparing two methods of neutrophil isolation.Neutrophils were isolated using ficoll density gradient centrifugation or immunomagnetic negative selection in two separate volunteers' cohorts. Subsequently, cells were lysed and incubated with chromogens for NE and MPO activity measurements, then measured with a microplate reader at 415 or 450 nm respectively.The enzymatic activity of NE and MPO depended on the neutrophil isolation technique. Both enzymatic activities were significantly higher (P 0.001) after isolating neutrophils with ficoll density gradient centrifugation than using the immunomagnetic negative selection.We demonstrated that neutrophil isolation is an important factor that influences the outcome of enzymatic activity measurements. Techniques based on immunomagnetic negative selection are favorable, specifically for investigations related to NE and MPO activity. When using NE and MPO activity measurements in clinical practice, care must be taken to interpret the data depending on the applied cell isolation technique.

Impaired neutrophil extracellular trap (NET) formation compromises the host defense after engraftment following hematopoietic stem cell transplantation (HSCT) despite adequate neutrophil counts. The aims of the present study were to determine reference ranges for the activity of key enzymes of NET formation—neutrophil elastase (NE) and myeloperoxidase (MPO)—in a healthy population and to unravel the recovery dynamics of NET formation over time following HSCT, along with NE and MPO enzymatic activities. Reference ranges of NE and MPO activity were derived from 50 healthy volunteers. During 2017 to 2018, 11 consecutive pediatric patients undergoing allogeneic or autologous HSCT were recruited at a single referral center for pediatric hemato-oncology. Patients were followed for up to 1 year following engraftment. The mean reference value was 7.5 ± .4 mU for NE activity and 2.17 ± .4 U for MPO activity in the healthy population, and enzymatic activity of MPO was significantly higher in males. At 3 weeks following neutrophil engraftment, all study participants demonstrated extremely low enzymatic NE activity, whereas MPO activity was above the lower normal reference range at all time points. Reduced NE activity corresponded to the inability to form NETs. Neutrophil function improved over time, but partial impairment persisted for 7 months following transplantation. The ability of neutrophils to form NETs was significantly impaired for 3 weeks after engraftment in the setting of HSCT, exposing patients to bacterial infections. NE activity might serve as a surrogate marker for the capacity of neutrophils to form NETs.

Heparanase is an endoglycosidase that specifically cleaves heparan sulfate (HS) side chains of heparan sulfate proteoglycans, the major proteoglycan in the extracellular matrix (ECM) and cell surfaces. Heparanase upregulation was documented in an increasing number of primary human tumors, correlating with reduced postoperative survival rate and enhanced tumor angiogenesis. The purpose of the current study was to determine heparanase levels in blood samples collected from pediatric cancer patients using an ELISA method. Heparanase levels were elevated four-fold in the plasma of cancer patients compared with healthy controls (664 ± 143 vs 163 ± 18 pg/ml, respectively). Evaluating plasma samples following anticancer therapy revealed reduced heparanase levels (664 ± 143 vs 429 ± 82 pg/ml), differences that are statistically highly significant (P = .0048). Of the 55 patients with complete remission (CR) or very good partial remission (VGPR) at restaging, 41 (74.5%) had lower heparanase amounts, whereas 14 patients (25.5%) had similar or higher amounts of plasma heparanase. All nine patients with stable or advancing disease had similar or elevated levels of heparanase on restaging. The results show that heparanase levels are elevated in the plasma of pediatric cancer patients and closely correlate with treatment responsiveness, indicating that heparanase levels can be used to diagnose and monitor patient's response to anticancer treatment.

In an attempt to abrogate the deleterious effects of graft-versus-host disease (GVHD), allogeneic transplantation for nonmalignant diseases was performed using high-dose CD34-cell infusion, partial T cell depletion, and no posttransplantation GVHD prophylaxis. Between 1998 and 2004, 16 patients with matched related donors were treated. Median age was 1.5 years (range, 5 months-18 years). The conditioning regimen consisted of busulphan 16 mg/kg, cyclophosphamide 200 mg/kg, antithymocyte globulin (ATG) 25 mg/kg, and fludarabine 200 mg/m 2 . No GVHD prophylaxis was given. High doses of CD34 cells, positively selected by immunomagnetic beads, were infused at a median dose of 10.7 × 10 6 CD34/kg (range, 7.4-50 × 10 6 ). A total of 1 × 10 5 /kg T cells were given. All patients engrafted, with no graft rejections. All were alive and well at a median of 37 months posttransplantation (range, 18-89 months). Only 1 patient developed chronic GVHD. No episodes of severe infection occurred during or after transplantation. Immunologic reconstitution with CD3/CD4 T cells > 200/μL was observed at a median of 117 days and that with naive T cells (CD4/CD45RA) at a median of 188 days posttransplantation. Our findings suggest that allogeneic transplantation from a matched family donor for nonmalignant disorders can be successfully performed using high doses of CD34 cells, moderate T cell depletion, and no posttransplantation immunosuppression.

GPC 0.37 0.59 0.36 0.27 GNR 0.35 0.12 0.3 0.23 Viral 0.72 1.28 1.34 0.0002 Adeno 0.15 0.38 0.25 0.03 BK 0.03 0.1 0.33

We present an extensive assessment of mutation burden through sequencing analysis of >81,000 tumors from pediatric and adult patients, including tumors with hypermutation caused by chemotherapy, carcinogens, or germline alterations. Hypermutation was detected in tumor types not previously associated with high mutation burden. Replication repair deficiency was a major contributing factor. We uncovered new driver mutations in the replication-repair-associated DNA polymerases and a distinct impact of microsatellite instability and replication repair deficiency on the scale of mutation load. Unbiased clustering, based on mutational context, revealed clinically relevant subgroups regardless of the tumors' tissue of origin, highlighting similarities in evolutionary dynamics leading to hypermutation. Mutagens, such as UV light, were implicated in unexpected cancers, including sarcomas and lung tumors. The order of mutational signatures identified previous treatment and germline replication repair deficiency, which improved management ofpatients and families. These data will inform tumor classification, genetic testing, and clinical trial design.

Near-haploid ( 50 chromosomes) ALL. We present three children in whom, by conventional cytogenetics, near-haploid ALL was detected on relapse. Using interphase FISH probes of chromosomes X, Y, 4, 12, and 21, we were able, in two cases, to trace the hidden near-haploid lines of approximately 5% and 20% of the cells, masked by hyperdiploid cells of approximately 80% and 70%, respectively; at relapse, the proportion was reversed, with predominant near-haploid lines of over 80% and residual hyperdiploidy of less than 10%. The near-haploid lines consisted of 24 and 27 chromosomes, and always retained the second copy of chromosome 21 or its derivative, as detected in one of our patients by SKY. The hyperdiploid clones were the exact duplicates of the near-haploid ones and contained four and two copies of the chromosomes represented in two and one copies in the near-haploid stem line, respectively. Unlike the common hyperdiploid ALL, no trisomies were observed. The patients were all aged >10 years, with WBC 0.7-30 x 10(9)/L, and a common ALL phenotype. They were treated with the ALL-BFM-95 protocol, medium risk group, and responded well to 8 days of steroid therapy, but relapsed early, within 11 months, and died a few months later. Interphase FISH technique is recommended for the detection of cryptic near-haploid clones in the diagnostic survey of ALL. To assess the prognostic value of near-haploidy in the context of the ALL-BFM protocols, a larger cohort of patients is required.

The effects of methylphenidate in 20 children with attention-deficit disorder between the ages of 7 and 12 years were assessed in a double-blind, placebo/drug counterbalanced study. Measures of outcome included the Teacher Rating Scale and Abbreviated Parent Rating Scale: digits, words, and visual sequencing; motor control; and a maze test. The Teacher Rating Scale placebo-drug difference correlated more significantly with the outcome measures than the baseline-drug difference. The study underlines the validity of a multimeasure placebo/drug trial in evaluating the efficacy of methylphenidate in children with attention-deficit disorder.