In vitro toxicity screening of magnetite nanoparticles by applying mesenchymal stem cells derived from human umbilical cord lining

Despite the growing interest in nanoparticles (NPs), their toxicity has not yet been defined and the development of new strategies and predictive models are required. Human stem cells (SCs) offer a promising and innovative cell‐based model. Among SCs, mesenchymal SCs (MSCs) derived from cord lining membrane (CL) may represent a new species‐specific tool for establishing efficient platforms for primary screening and toxicity/safety testing of NPs. Superparamagnetic iron oxide NPs, including magnetite (Fe₃O₄NPs), have aroused great public health and scientific concerns despite their extensive uses. In this study, CL‐MSCs were characterized and applied for in vitro toxicity screening of Fe₃O₄NPs. Cytotoxicity, internalization/uptake, differentiation and proliferative capacity were evaluated after exposure to different Fe₃O₄NP concentrations. Data were compared with those obtained from bone marrow (BM)‐MSCs. We observed, at early passages (P3), that: (1) cytotoxicity occurred at 10 μg/mL in CL‐MSCs and 100 μg/mL in BM‐MSCs (no differences in toxicity, between CL‐ and BM‐MSCs, were observed at higher dosage, 100‐300 μg/mL); (2) cell density decrease and monolayer features loss were affected at ≥50 μg/mL in CL‐MSCs only; and (3) NP uptake was concentration‐dependent in both MSCs. After 100 μg/mL Fe₃O₄NP exposures, the capacity of proliferation was decreased (P5‐P9) in CL‐MSCs without morphology alteration. Moreover, a progressive decrease of intracellular Fe₃O₄NPs was observed over culture time. Antigen surface expression and multilineage differentiation were not influenced. These findings suggest that CL‐MSCs could be used as a reliable cell‐based model for Fe₃O₄NP toxicity screening evaluation and support the use of this approach for improving the confidence degree on the safety of NPs to predict health outcomes.     

CGRP Plasma Levels Correlate with the Clinical Evolution and Prognosis of Hospitalized Acute COVID-19 Patients

SARS-CoV-2 is the etiological agent of COVID-19, an extremely heterogenous disease that can cause severe respiratory failure and critical illness. To date, reliable biomarkers allowing for early patient stratification according to disease severity are still lacking. Calcitonin gene-related peptide (CGRP) is a vasoactive neuropeptide involved in lung pathophysiology and immune modulation and is poorly investigated in the COVID-19 context. In this observational, prospective cohort study, we investigated the correlation between CGRP and clinical disease evolution in hospitalized moderate to severe COVID-19 patients. Between January and May 2021 (Italian third pandemic wave), 135 consecutive SARS-CoV-2 patients were diagnosed as being eligible for the study. Plasma CGRP level evaluation and routine laboratory tests were performed on blood samples collected at baseline and after 7 days of hospitalization. At baseline, the majority our patients had a moderate to severe clinical presentation, and higher plasma CGRP levels predicted a higher risk of in-hospital negative evolution (odds-ratio OR 2.84 [IQR 1.07–7.51]) and were correlated with pulmonary intravascular coagulopathy (OR 2.92 [IQR 1.19–7.17]). Finally, plasma CGRP levels were also correlated with plasma IP10 levels. Our data support a possible crosstalk between the lung and the neuroimmune axis, highlighting a crucial role for plasma CGRP in sustaining COVID-19-related hyperinflammation.     

Chronic cerebrospinal venous insufficiency (CCSVI) and multiple sclerosis (MS): a critical review

Multiple sclerosis (MS) is a chronic disease of the central nervous system with not yet completely understood pathogenesis. The so called "chronic cerebrospinal venous insufficiency (CCSVI) theory" has recently emerged, supporting the concept of a cerebrospinal venous drainage impairment as the cause of MS. Since the first publication on this topic with a claimed 100% specificity and sensitivity of the condition for MS diagnosis, CCSVI theory has generated a scientific and mass media debate with a great hope for the miracle of a new possible endovascular treatment of MS ("liberation procedure"). We critically summarize the available evidence on CCSVI discussing inconsistent and incomplete replication of the original results by different groups, methodological limitations and potential therapeutic implications. We conclude that the available data are insufficient to establish conclusively a clear relationship between MS and CCSVI and do not support the role of CCSVI as the primary cause of MS. Until credible scientific evidence replicates the original results, any proposed invasive treatments of CCSVI should be discouraged.     

Hematopoietic stem cell transplantation for children with high-risk acute lymphoblastic leukemia in first complete remission: a report from the AIEOP registry

Children with high-risk acute lymphoblastic leukemia in first complete remission can benefit from allogeneic hematopoietic stem cell transplantation. We analyzed the outcome of 211 children with high-risk acute lymphoblastic leukemia in first complete remission who were given an allogeneic transplant between 1990 and 2008; the outcome of patients who, despite having an indication for transplantation and a suitable donor, did not receive the allograft for different reasons in the same time period was not analyzed. Sixty-nine patients (33%) were transplanted between 1990 and 1999, 58 (27%) between 2000 and 2005, and 84 (40%) between 2005 and 2008. A matched family donor was employed in 138 patients (65%) and an unrelated donor in 73 (35%). The 10-year probabilities of overall and disease-free survival were 63.4% and 61%, respectively. The 10-year cumulative incidences of transplantation-related mortality and relapse were 15% and 24%, respectively. After 1999, no differences in either disease-free survival or transplant-related mortality were observed in patients transplanted from unrelated or matched family donors. In multivariate analysis, grade IV acute graft-versus-host disease was an independent factor associated with worse disease-free survival. By contrast, grade I acute graft-versus-host disease and age at diagnosis between 1 and 9 years were favorable prognostic variables. Our study, not intended to evaluate whether transplantation is superior to chemotherapy for children with acute lymphoblastic leukemia in first complete remission and high-risk features, shows that the allograft cured more than 60% of these patients; in the most recent period, the outcome of recipients of grafts from matched family and unrelated donors was comparable.     

Experts’ considerations on HLA‐haploidentical stem cell transplantation

Recently, novel strategies to control graft‐versus‐host disease and facilitate engraftment have allowed an increasing number of human leukocyte antigen (HLA)‐haploidentical hematopoietic stem cell transplantation (haploHSCT) to be performed. A meeting was convened to review the biological rationale and the clinical results of various T‐cell‐depleted (TCD) and T‐cell‐replete (TCR) HLA‐haploidentical ‘transplant platforms’. The objective of the meeting was to promote discussion and consent among leading researchers in the field on three main crucial issues for haploHSCT: (i) eligibility criteria, (ii) choice of the most suitable donor, and (iii) choice of the most appropriate transplant platform. The experts in attendance agreed that a patient who is eligible for an allogeneic transplant and lacks an HLA‐identical sibling or an HLA‐matched unrelated donor should be considered for an alternative donor transplant. Together with the experience of the individual center, the most important decision criteria in choosing an alternative donor source should be the rapidity of transplantation so as to avoid disease relapse/progression. The choice of the mismatched donor should be driven by younger age, ABO blood group compatibility, and Cytomegalovirus status. If a TCD transplant is planned, NK‐alloreactive donors and/or the mother should be preferred. Prospective comparative studies are needed to establish the relative efficacy of different transplant platforms. However, expertise in stem cell manipulation and in adoptive immunotherapy is essential if a TCD transplant platform is chosen.     

Clofarabine, cyclophosphamide and etoposide as single-course re-induction therapy for children with refractory/multiple relapsed acute lymphoblastic leukaemia

The safety and efficacy of the combination clofarabine/cyclophosphamide/etoposide were evaluated in children with advanced acute lymphoblastic leukaemia (ALL). The study enrolled 25 paediatric patients (median age 12·5 years) with either refractory ( n  = 17; 68%) or multiple relapsed ( n  = 8; 32%) ALL to receive clofarabine 40 mg/m², cyclophosphamide 400 mg/m² and etoposide 150 mg/m², daily for 5 consecutive days. No patient died from treatment-related complications. The most common adverse events were febrile neutropenia, mucositis and reversible liver toxicity; no case of liver veno-occlusive disease was reported. The overall remission rate was 56%: 13 patients (52%) achieved complete remission (CR) and one (4%) CR without platelet recovery (CRp). In seven of the 13 (54%) patients achieving CR, remissions were of sufficient duration to allow patients to receive allogeneic haematopoietic stem cell transplantation. The probability of CR/CRp was greater in the 17 patients with B cell precursor ALL than in the eight with T-ALL (76% vs. 12%, respectively, P  <   0·01). The 18-month overall survival probability was 39% and 0% in patients who did or did not respond to the treatment, respectively ( P  <   0·01). These data suggest that the clofarabine/cyclophosphamide/etoposide regimen is well tolerated and can induce clinical response in a relevant proportion of children with refractory/multiple relapsed ALL.     

Effect of fast vs slow intralipid infusion on gas exchange, pulmonary hemodynamics, and prostaglandin metabolism

Intralipid (20 percent, 500 ml) was infused fast (5 h) or slow (10 h) randomly in patients with lung injury to relate changes in plasma prostaglandin (PG) concentrations to gas exchange and pulmonary hemodynamics. Data were collected at baseline, midpoint of infusion, and 2 h following infusion. Vasodilator and vasoconstrictor PG metabolites, 6-keto-PGF1 alpha, and thromboxane B2, respectively, were measured in radial arterial blood samples. Slow Intralipid infusion increased shunt fraction (QS/QT) without changing mean pulmonary artery pressure (MPAP), whereas fast Intralipid infusion increased MPAP without changing QS/QT. Prostaglandin levels did not change significantly during either infusion. However, in both groups when the PG substrate was removed, hemodynamic and metabolite values decreased in parallel. In conclusion, we were unable to demonstrate a cause and effect relationship between plasma levels of 6-keto-PGF1 alpha and thromboxane B2 and the observed pulmonary hemodynamic response to slow or fast Intralipid infusion.     

Recombinant human erythropoietin may correct erythropoietin-deficient hyporegenerative anaemia in children given cardiac transplantation

Summary. Cyclosporin-A reduces erythropoietin production and, together with the inhibitory effect of cytokines on erythropoiesis, may be potentially responsible for the anaemia observed in some patients after heart transplantation. Two children given cardiac transplantation and receiving cyclosporin-A developed transfusion-dependent hyporegenerative anaemia. Erythropoietin production was inappropriately low for the degree of anaemia, with an observed/predicted log(serum EPO) ratio of 0.54 and 0.49, respectively. The children were treated with rHuEPO at a dose of 75U/kg three times weekly for 1 month and then twice weekly via subcutaneous injection. No further transfusion was necessary and restoration of normal erythroid activity was obtained, with normal haemoglobin values. No adverse effects were observed. Our experience suggests that recombinant human erythropoietin may be useful in treating the anaemia associated with cardiac transplantation.