Treosulfan-Based Conditioning Regimen In Pediatric Hematopoietic Stem Cell Transplantation: A Retrospective Analysis on Behalf of the Spanish Group for Hematopoietic Transplantation and Cellular Therapy (GETH-TC).

Increasing data on treosulfan-based conditioning regimens before hematopoietic stem cell transplantation (HSCT) demonstrate the consistent benefits of this approach, particularly regarding acute toxicity. This study aimed to describe the results of treosulfan-based conditioning regimens in children, focusing on toxicity and outcomes when used to treat both malignant and nonmalignant diseases. This retrospective observational study of pediatric patients treated in Spain with treosulfan-based conditioning regimens before HSCT was based on data collection from electronic clinical records. We studied a total of 160 treosulfan-based conditioning HSCTs to treat nonmalignant diseases (n = 117) or malignant diseases (n = 43) in 158 children and adolescents. The median patient age at HSCT was 5.1 years (interquartile range, 2 to 10 years). The most frequent diagnoses were primary immunodeficiency (n = 42; 36%) and sickle cell disease (n = 42; 36%) in the nonmalignant disease cohort and acute lymphoblastic leukemia (n = 15; 35%) in the malignant disease cohort. Engraftment occurred in 97% of the patients. The median times to neutrophil engraftment (17 days versus 14 days; P = .008) and platelet engraftment (20 days versus 15 days; P = .002) were linger in the nonmalignant cohort. The 1-year cumulative incidence of veno-occlusive disease was 7.98% (95% confidence interval [CI], 4.6% to 13.6%), with no significant differences between cohorts. The 1-year cumulative incidence of grade III-IV acute graft-versus-host disease (GVHD) was higher in the malignant disease cohort (18% versus 3.2%; P = .011). Overall, the malignant cohort had both a higher total incidence (9% versus 3%; P < .001) and a higher 2-year cumulative incidence (16% versus 1.9%; P < .001) of total chronic GVHD. The 2-year cumulative transplantation-related mortality was 15%, with no difference between the 2 cohorts. The 5-year overall survival was 80% (95% CI, 72% to 86%) and was higher in the nonmalignant cohort (87% versus 61%; P = .01). The 2-year cumulative incidence of relapse was 25% in the malignant cohort. The 5-year cumulative GVHD-free, relapse-free survival rate was 60% (95% CI, 51% to 70%) and was higher in the nonmalignant cohort (72% versus 22%; P < .001). A treosulfan-based radiation-free conditioning regimen is feasible, achieving a high engraftment rate and 5-year overall survival, and is an emerging option for the first HSCT in nonmalignant diseases.

Estimation by flow cytometry of percentages of survival of Listeria monocytogenes cells treated with tetracycline, with or without prior exposure to several biocides.

In certain circumstances, disinfectants are used at sublethal concentrations. The aim of this research work was to determine whether contact of Listeria monocytogenes NCTC 11994 with subinhibitory concentrations of three disinfectants widely used in food processing environments and in the health-care system, benzalkonium chloride (BZK), sodium hypochlorite (SHY) and peracetic acid (PAA), can cause the adaptation of the strain to the biocides and increase its resistance to tetracycline (TE). The minimum inhibitory concentrations (MIC; ppm) were 2.0 (BZK), 3500.0 (SHY) and 1050.0 (PAA). On exposure to increasing subinhibitory concentrations of the biocides, the maximum concentrations (ppm) of the compounds that allowed the strain to grow were (ppm) 8.5 (BZK), 3935.5 (SHY) and 1125.0 (PAA). Both the control cells (non-exposed) and the cells that had been in contact with low doses of biocides were treated with different concentrations of TE (0 ppm, 250 ppm, 500 ppm, 750 ppm, 1000 ppm and 1250 ppm) for 24, 48 and 72 h, and the survival percentages determined using flow cytometry, following dying with SYTO 9 and propidium iodide. The cells previously exposed to PAA presented higher survival percentages (P < 0.05) than the rest of the cells for most of the concentrations of TE and treatment times trialled. These results are worrying because TE is sometimes used to treat listeriosis, highlighting the importance of avoiding the use of disinfectant at subinhibitory doses. Furthermore, the findings suggest that flow cytometry is a fast and simple technique to obtain quantitative data on bacterial resistance to antibiotics.

The Effectiveness of Plasma Rich in Growth Factors (PRGF) in the Treatment of Nerve Compression Syndromes of the Upper Extremity: A Retrospective Observational Clinical Study.

Background: Nerve compression syndromes of the upper extremity are a common cause of neuropathic pain and functional impairment. Recently, platelet-rich plasma (PRP) infiltrations have emerged as an effective biological approach to the treatment of this type of injury. The objectives of this retrospective observational study were to assess clinical improvement in patients with median and ulnar nerve entrapment syndrome after undergoing biologically-assisted nerve release surgery with plasma-rich-in-growth-factors (PRGF) technology. Methods: Participants (n = 39) with moderate-to-severe nerve compression syndrome of the upper limb diagnosed by both electromyography and clinical examination, and who were treated with PRGF, were identified from the center's medical records. The evaluation was based on patient-reported outcomes. Pre- and post-treatment differences in the Visual analog scale (VAS), the Boston carpal tunnel questionnaire (BCTQ), and the Quick-DASH score were assessed. Results: Three study groups were conducted: patients with carpal tunnel syndrome (n = 16), with recurrent carpal tunnel syndrome (n = 8), and with ulnar nerve entrapment (n = 15). The median follow-up was 12 months (interquartile range (IQR), 9−16). In comparison to pre-treatment values, all three study groups obtained statistically significant improvements for the three analyzed scales at the end of the follow-up, with p < 0.001 for all scales in the carpal tunnel syndrome and ulnar nerve entrapment groups and p < 0.01 for all scales in the recurrent carpal tunnel syndrome group. There were no serious adverse effects in the analyzed patients. Conclusion: PRGF-assisted open surgical nerve release treatment (intraneural and perineural liquid PRGF infiltrations and nerve wrapping with PRGF membrane) exerts long-term beneficial effects on pain reduction and functional improvement in the nerve and nerve−muscle unit in patients with upper extremity compression syndromes.

Ruxolitinib does not completely abrogate the functional capabilities of TLR4/9 ligand-activated NK cells.

Introduction: Natural killer (NK) cells are lymphocytes from the innate immune system part of the first defense barrier against infected and transformed cells, representing 5%-15% of peripheral blood lymphocytes. The cytotoxic capacity of NK cells is controlled by a balance between inhibitory and activating NK receptors expressed on their surface, which recognize and interact with the ligands on stressed cells. The cytokines involved in NK cell activation, proliferation, survival, and cytotoxicity are signaled mainly through the Janus kinase and signal transducer and activator of transcription proteins (JAK/STAT) pathway. NK cells are also activated in response to pathogens through Toll-like receptors (TLRs) expressed on their surface. Ruxolitinib is a specific JAK1/2 inhibitor approved for treating myelofibrosis and for steroid-refractory acute and chronic graft-versus-host disease (SR-GvHD). Methods: Purified NK cells from healthy donors were stimulated with two TOLL-like receptor ligands, LPS and CpG, in the presence of different concentrations of Ruxolitinib. Results: This study showed the effects of ruxolitinib on TLR4 and TLR9 ligand-activated NK cells from healthy donors. Ruxolitinib did not completely inhibit STAT3 phosphorylation and had a moderate effect on NK cell cytokine activation via the TLR pathway. Only the highest doses of ruxolitinib led to a decrease in the pro-inflammatory cytokines tumor necrosis factor α, interferon-γ, interleukin-6, and interleukin-1ß. The cytotoxic capacity of stimulated NK cells versus K562, SEM, and MV-4-11 cell lines was reduced by increasing doses of ruxolitinib, but it was not completely abolished and we observed no major changes in degranulation capacity. Phenotypic changes were observed in activated NK cells in the presence of ruxolitinib. In a small cohort of pediatric patients treated with ruxolitinib for SR-GvHD, we observed no decrease in NK cell counts; however, further prospective studies with larger cohorts are necessary to confirm this finding. Discussion: In summary, our results showed that the functional capabilities and phenotype of NK cells activated through TLR4/9 agonists were not completely abolished by the inhibition of the JAK-STAT pathway by ruxolitinib.

Phase 2 Clinical Trial of Infusing Haploidentical K562-mb15-41BBL-Activated and Expanded Natural Killer Cells as Consolidation Therapy for Pediatric Acute Myeloblastic Leukemia.

BACKGROUND: Acute myeloid leukemia (AML) accounts for approximately 20% of pediatric leukemia cases; 30% of these patients experience relapse. The antileukemia properties of natural killer (NK) cells and their safety profile have been reported in AML therapy. We proposed a phase 2, open, prospective, multicenter, nonrandomized clinical trial for the adoptive infusion of haploidentical K562-mb15-41BBL-activated and expanded NK (NKAE) cells as a consolidation strategy for children with favorable and intermediate risk AML in first complete remission after chemotherapy (NCT02763475). PATIENTS AND METHODS: Before the NKAE cell infusion, patients underwent a lymphodepleting regimen. After the NKAE cell infusion, patients were administered low doses (1 × 106/IU/m2) of subcutaneous interleukin-2. The primary study endpoint was AML relapse-free survival. We needed to include 35 patients to demonstrate a 50% reduction in relapses. RESULTS: Seven patients (median age, 7.4 years; range, 0.78-15.98 years) were administered 13 infusions of NKAE cells, with a median of 36.44 × 106 cells/kg (range, 6.92 × 106 to 193.2 × 106 cells/kg). We observed chimerism in 4 patients (median chimerism, 0.065%; range, 0.05-0.27%). After a median follow-up of 33 months, the disease of 6 patients (85.7%) remained in complete remission. The 3-year overall survival was 83.3% (95% confidence interval, 68.1-98.5), and the cumulative 3-year relapse rate was 28.6% (95% confidence interval, 11.5-45.7). The study was terminated early because of low patient recruitment. CONCLUSION: This study emphasizes the difficulties in recruiting patients for cell therapy trials, though NKAE cell infusion is safe and feasible. However, we cannot draw any conclusions regarding efficacy because of the small number of included patients and insufficient biological markers.

MIBG Therapy for Neuroblastoma: Precision Achieved With Dosimetry, and Concern for False Responders.

Neuroblastoma causes 15% of cancer mortality in children. High risk neuroblastoma has poor prognosis, with high relapse rate and mortality despite multimodal treatment. 123-I-meta-iodo-benzyl-guanidine (mIBG) scintigraphy is one of the current standard diagnostic procedures in neuroblastoma. mIBG can also be used therapeutically, labeled with 131-I, as a radiopharmaceutical agent, delivering targeted radiotherapy to tumoral sites. But published data of this strategy show heterogeneous results. One concern is that in most reports the infused activity is only based in body-weight, which could lead to infra or over-treatment, depending on inter-patient variability in radiation absorption. Activity adjustment by whole-body dosimetry can be used to homogeneize the treatment. Also, mIBG avid tumors may lose avidness along the treatment. As mIBG is used both for treatment and response evaluation, this could result in undetected progressions in patients with apparent complete response. We present a retrospective single-center review of neuroblastoma patients who received therapeutic 131-I-mIBG, focusing on cases with dosimetry-adjusted activity. Dosimetry allowed for a more precise delivery of radiation, reducing 81.1% of deviation from absorption target of 4 Gray (Gy), from 23.4% (±0.936 Gy) to 4.4% (± 0.176 Gy). Patients who showed partial or complete response had better and longer survival. Relapse/progression in non-responders was an early event (within 3 months from treatment). We also present one case of progression with apparent complete response due to loss of mIBG avidness, detected in our series.