A randomized multicenter study: safety and efficacy of mini-pool intravenous immunoglobulin versus standard immunoglobulin in children aged 1-18 years with immune thrombocytopenia

Stepwise options for preparing therapeutic plasma proteins from domestic plasma in low- and middle-income countries

Industrial plasma fractionation, a complex and highly regulated technology, remains largely inaccessible to many low- and middle-income countries (LMICs). This, combined with the limited availability and high cost of plasma-derived medicinal products (PDMPs), creates deficiency of access to adequate treatment for patients in resource-limited countries, and leads to their suffering. Meanwhile, an increasing number of LMICs produce surplus plasma, as a by-product of red blood cell preparation from whole blood, that is discarded because of the lack of suitability for fractionation. This article reviews pragmatic technological options for processing plasma collected from LMICs into therapies and supports a realistic stepwise approach aligned with recent World Health Organization guidance and initiatives launched by the Working Party for Global Blood Safety of the International Society of Blood Transfusion. When industrial options based on contract or toll plasma fractionation programme and, even more, domestic fractionation facilities require larger volumes of quality plasma than is produced, alternative methods should be considered. In-bag minipool or small-scale production procedures implementable in blood establishments or national service centres are the only realistic options available to gradually reduce plasma wastage, provide safer treatments for patients currently treated with non-pathogen-reduced blood products and concurrently improve Good Manufacturing Practice (GMP) levels with minimum capital investment. As a next step, when the available volume of quality-assured plasma reaches the necessary thresholds, LMICs could consider engaging with an established fractionator in a fractionation agreement or a contract in support of a domestic fractionation facility to improve the domestic PDMP supply and patients' treatment.

Immunoglobulin and Monoclonal Antibody Therapies in Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is an acute autoimmune polyradiculoneuropathy affecting 1-2 subjects per 100,000 every year worldwide. It causes, in its classic form, symmetric weakness in the proximal and distal limb muscles with common involvement of the cranial nerves, particularly facial weakness. Respiratory function is compromised in a case in four. Randomised controlled trials have demonstrated the benefit of therapeutic plasma exchange in hastening time to recovery. Intravenous immunoglobulin was subsequently shown to be as efficacious as plasma exchange in adult subjects. In children, few trials have shown the benefit of intravenous immunoglobulin versus supportive care. Pharmacokinetic studies suggested a relationship between increase in immunoglobulin G level post-infusion and outcome, implying administration of larger doses may be beneficial in subjects with poor prognosis. However, a subsequent trial of a second dose of immunoglobulin in such subjects failed to show improved outcome, while demonstrating a higher risk of thromboembolic side-effects. Monoclonal antibody therapy has more recently been investigated for GBS, after multiple studies in animal models, with different agents and variable postulated mechanisms of action. Eculizumab, a humanised monoclonal antibody against the complement protein C5, was tested in in two randomised, double-blind, placebo-controlled phase 2 trials. Neither showed benefit versus immunoglobulins alone on disability level at 4 weeks, although one study importantly suggested possible, clinically highly relevant, late effects on normalising function. A phase 3 trial is in progress. Preliminary results of a placebo-controlled ongoing study of ANX005, a humanised recombinant antibody against C1q inhibiting the complement cascade, have been promising.

Updated international consensus report on the investigation and management of primary immune thrombocytopenia

Over the last decade, there have been numerous developments and changes in treatment practices for the management of patients with immune thrombocytopenia (ITP). This article is an update of the International Consensus Report published in 2010. A critical review was performed to identify all relevant articles published between 2009 and 2018. An expert panel screened, reviewed, and graded the studies and formulated the updated consensus recommendations based on the new data. The final document provides consensus recommendations on the diagnosis and management of ITP in adults, during pregnancy, and in children, as well as quality-of-life considerations.

N-acetyl-L-cysteine improves bone marrow endothelial progenitor cells in prolonged isolated thrombocytopenia patients post allogeneic hematopoietic stem cell transplantation

Prolonged isolated thrombocytopenia (PT) is a serious complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). According to murine studies, endothelial progenitor cells (EPCs) play a crucial role in the regulation of hematopoiesis and thrombopoiesis in the bone marrow (BM) microenvironment. We previously showed that the reduced frequency of BM EPCs was an independent risk factor for the occurrence of PT following allo-HSCT. However, the functional role of BM EPCs and methods to improve the impaired BM EPCs in PT patients are unknown. In the current case-control study, we investigated whether the BM EPCs in PT patients differed from those in good graft function patients. Moreover, we evaluated whether N-acetyl-L-cysteine (NAC, a reactive oxygen species [ROS] scavenger) could enhance BM EPCs from PT patients in vitro and in vivo. The PT patients exhibited dysfunctional BM EPCs characterized by high levels of ROS and apoptosis and decreased migration and angiogenesis capabilities. In vitro treatment with NAC improved the quantity and function of the BM EPCs cultivated from the PT patients by downregulating the p38 MAPK pathway and rescued the impaired BM EPCs to support megakaryocytopoiesis. Furthermore, according to the results of a preliminary clinical study, NAC is safe and effective in PT patients. In summary, these results suggested that the reduced and dysfunctional BM EPCs are involved in the occurrence of PT. The defective BM EPCs in the PT patients can be quantitatively and functionally improved by NAC, indicating that NAC is a promising therapeutic approach for PT patients following allo-HSCT.

N-acetyl-L-cysteine improves mesenchymal stem cell function in prolonged isolated thrombocytopenia post-allotransplant

Prolonged isolated thrombocytopenia (PT) is a serious complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT). Murine studies and in vitro experiments suggest that mesenchymal stem cells (MSCs) can, not only to support haematopoiesis, but also preferentially support megakaryocytopoiesis in bone marrow (BM). However, little is known about the quantity and function of BM MSCs in PT patients. In a case-control study, we found that BM MSCs from PT patients exhibited significantly reduced proliferative capacities, increased reactive oxygen species and senescence. Antioxidant (N-acetyl-L-cysteine, NAC) treatment in vitro not only quantitatively and functionally improved BM MSCs derived from PT patients through down-regulation of the p38 (also termed MAPK14) and p53 (also termed TP53) pathways but also partially rescued the impaired ability of BM MSCs to support megakaryocytopoiesis. Subsequently, a pilot study showed that the overall response of NAC treatment was obtained in 7 of the enrolled PT patients (N = 10) without significant side effects. Taken together, the results indicated that dysfunctional BM MSCs played a role in the pathogenesis of PT and the impaired BM MSCs could be improved by NAC in vitro. Although requiring further validation, our data indicate that NAC might be a potential therapeutic approach for PT patients after allo-HSCT.