Two-center validation of assays for the detection of binding and neutralizing anti-factor VIII antibodies

INTRODUCTION

Patients with hemophilia A treated with coagulation Factor VIII (FVIII) products are at risk for developing anti-FVIII antibodies. The ABIRISK Consortium aimed to provide knowledge on the formation and detection of anti-drug antibodies against biopharmaceutical products, including FVIII. Accordingly, standardized and validated assays for the detection of binding (total) and neutralizing antibodies are needed.

AIM

Two-center validation of an ELISA for the detection of total FVIII-binding IgG-antibodies and Nijmegen-Bethesda assays for the quantification of FVIII-neutralizing antibodies according to consensus validation guidelines.

METHODS

Validation of assays at both sites was done according to published recommendations and included preanalytics, the determination of key assay parameters, including cut-points, assay sensitivity, precision, and FVIII interference.

RESULTS

The validated assays reproducibly detected FVIII-binding and -neutralizing antibodies with comparable performance in both laboratories. Floating screening cut-points were established for both assays. Determined mass-based sensitivity of both assays (all values ≤66 ng/mL) complied with the minimum sensitivity for the detection of anti-drug antibodies as recommended by the FDA (<100 ng/mL). Intra- and inter-assay coefficients of variation did not exceed 25%. Assay validation further revealed that pre-analytical heat treatment led to potentially false-positive ELISA results, while up to 0.15 IU/mL, residual FVIII showed no significant impact. Overall, good agreement of results was found for patient samples analyzed at both study sites.

CONCLUSION

Comprehensive validation of different anti-FVIII-antibody assays in two laboratories gave novel insights into the impact of pre-analytical sample treatment as well as the comparability of test results generated by the use of methodically different assays.

Distribution and Morphology of α-Al, Si and Fe-Rich Phases in Al-Si-Fe Alloys under an Electromagnetic Field

Natural convection is present in all liquid alloys whereas forced convection may be applied as the method to improve material properties. To understand the effect of forced convection, the solidification in simple cylindrical samples was studied using a rotating magnetic field with a low cooling rate and low temperature gradient. The composition of Al-Si-Fe alloys was chosen to enable independent growth or joint growth of occurring α-Al, β-Al₅FeSi, δ-AlFeSi_T4 phases and Si crystals and analysis of structure modifications. Stirring produced rosettes instead of equiaxed dendrites, which altered the secondary dendrite arm spacing and the specific surface of α-Al and also modified β-Al₅FeSi. The melt flow caused a modification of iron rich δ-AlFeSi_T4 phases and gathered them inside the sample of the β/Si alloy, where δ together with Si were the first precipitating phases. The separation of δ and β phases and Si crystals was found by their joint growth along the monovariant line. A reduction in the amount of Si crystals and the formation of a thin Si-rich layer outside the sample was observed in the hypereutectic alloy. The separation and reduction in iron-rich phases may play a role in the removal of Fe from Al-Si alloys, and the control of Si may be applied in materials for the solar photovoltaic industry.

Extracellular Vesicles as Diagnostics and Therapeutics for Structural Epilepsies

Extracellular vesicles (EVs) are small vesicles involved in intercellular communication. Data is emerging that EVs and their cargo have potential as diagnostic biomarkers and treatments for brain diseases, including traumatic brain injury and epilepsy. Here, we summarize the current knowledge regarding changes in EV numbers and cargo in status epilepticus (SE) and traumatic brain injury (TBI), which are clinically significant etiologies for acquired epileptogenesis in animals and humans. We also review encouraging data, which suggests that EVs secreted by stem cells may serve as recovery-enhancing treatments for SE and TBI. Using Gene Set Enrichment Analysis, we show that brain EV-related transcripts are positively enriched in rodent models of epileptogenesis and epilepsy, and altered in response to anti-seizure drugs. These data suggest that EVs show promise as biomarkers, treatments and drug targets for epilepsy. In parallel to gathering conceptual knowledge, analytics platforms for the isolation and analysis of EV contents need to be further developed.

Potential strategies for sustainably financing mental health care in Uganda

BACKGROUND

In spite of the pronounced adverse economic consequences of mental, neurological, and substance use disorders on households in most low- and middle-income countries, service coverage and financial protection for these families is very limited. The aim of this study was to generate potential strategies for sustainably financing mental health care in Uganda in an effort to move towards increased financial protection and service coverage for these families.

METHODS

The process of identifying potential strategies for sustainably financing mental health care in Uganda was guided by an analytical framework developed by the Emerging Mental health systems in low and middle income countries (EMERALD project). Data were collected through a situational analysis (public health burden assessment, health system assessment, macro fiscal assessment) and eight key informant interviews with selected stakeholders from sectors including health, finance and civil society. The situational analysis provided contextualization for the strategies, and was complimented by views from key informant interviews.

RESULTS

Findings indicate that the following strategies have the greatest potential for moving towards more equitable and sustainable mental health financing in the Uganda context: implementing National Health Insurance Scheme; shifting to Results Based Financing; decentralizing mental health services that can be provided at community level; and continued advocacy with decision makers with evidence through research.

CONCLUSION

Although several options were identified for sustainably financing mental health care in Uganda, the National Health Insurance Scheme seemed the most viable option. However, for the scheme to be effective, there is need for scale up to community health facilities and implementation in a manner that explicitly includes community level facilities.

Environmental isolation explains Iberian genetic diversity in the highly homozygous model grass Brachypodium distachyon

BACKGROUND

Brachypodium distachyon (Poaceae), an annual Mediterranean Aluminum (Al)-sensitive grass, is currently being used as a model species to provide new information on cereals and biofuel crops. The plant has a short life cycle and one of the smallest genomes in the grasses being well suited to experimental manipulation. Its genome has been fully sequenced and several genomic resources are being developed to elucidate key traits and gene functions. A reliable germplasm collection that reflects the natural diversity of this species is therefore needed for all these genomic resources. However, despite being a model plant, we still know very little about its genetic diversity. As a first step to overcome this gap, we used nuclear Simple Sequence Repeats (nSSR) to study the patterns of genetic diversity and population structure of B. distachyon in 14 populations sampled across the Iberian Peninsula (Spain), one of its best known areas.

RESULTS

We found very low levels of genetic diversity, allelic number and heterozygosity in B. distachyon, congruent with a highly selfing system. Our results indicate the existence of at least three genetic clusters providing additional evidence for the existence of a significant genetic structure in the Iberian Peninsula and supporting this geographical area as an important genetic reservoir. Several hotspots of genetic diversity were detected and populations growing on basic soils were significantly more diverse than those growing in acidic soils. A partial Mantel test confirmed a statistically significant Isolation-By-Distance (IBD) among all studied populations, as well as a statistically significant Isolation-By-Environment (IBE) revealing the presence of environmental-driven isolation as one explanation for the genetic patterns found in the Iberian Peninsula.

CONCLUSIONS

The finding of higher genetic diversity in eastern Iberian populations occurring in basic soils suggests that these populations can be better adapted than those occurring in western areas of the Iberian Peninsula where the soils are more acidic and accumulate toxic Al ions. This suggests that the western Iberian acidic soils might prevent the establishment of Al-sensitive B. distachyon populations, potentially causing the existence of more genetically depauperated individuals.

Immunotherapy after hematopoietic stem cell transplantation using umbilical cord blood-derived products

Umbilical cord blood (UCB) is being increasingly used as a source of hematopoietic stem cells (HSC) for transplantation. UCB transplantation (UCBT) has some advantages such as less stringent HLA-matching requirements, fast availability of the graft and reduced incidence and severity of graft-versus-host disease. However, UCBT is also associated with a higher incidence of infection, graft failure, slow engraftment and slow immune reconstitution. UCB is mainly used as a source of HSC; however, it is also rich in immune cells that could be used to treat some of the main complications post-UCBT as well as other diseases, thus implicating the use of UCB for immunotherapy. Here, we aim to describe some of the therapies currently developed that use UCB as a cell source, focusing in particular on regulatory T cells and natural killer cells.

Magnetically-Responsive Hydrogels for Modulation of Chondrogenic Commitment of Human Adipose-Derived Stem Cells

Magnetic nanoparticles (MNPs) are attractive tools to overcome limitations of current regenerative medicine strategies, demonstrating potential to integrate therapeutic and diagnostic functionalities in highly controlled systems. In traditional tissue engineering (TE) approaches, the MNPs association with stem cells in a three-dimensional (3D) template offers the possibility to achieve a mechano-magnetic responsive system, enabling remote control actuation. Herein, we propose to study the role of MNPs integrated in κ-carrageenan (κC) hydrogels in the cellular response of human adipose-derived stem cells (hASCs) aiming at cartilage TE applications. The results indicated that the concentration of MNPs in the κC hydrogels influences cellular behavior, tuning a positive effect on cell viability, cell content and metabolic activity of hASCs, with the most promising outcomes found in 5% MNP-κC matrices. Although hASCs laden in MNPs-free- and MNPs-κC hydrogels showed similar metabolic and proliferation levels, MNPs κC hydrogels under magnetic actuation evidenced an instructive effect on hASCs, at a gene expression level, towards chondrogenic phenotype even in basic medium cultures. Therefore, the MNPs-based systems developed in this study may contribute to advanced strategies towards cartilage-like engineered substitutes.