Non‐productive exposure of PBMCs to SARS‐CoV ‐2 induces cell‐intrinsic innate immune responses

Cell‐intrinsic responses mounted in PBMCs during mild and severe COVID‐19 differ quantitatively and qualitatively. Whether they are triggered by signals emitted by productively infected cells of the respiratory tract or result from physical interaction with virus particles remains unclear. Here, we analyzed susceptibility and expression profiles of PBMCs from healthy donors upon ex vivo exposure to SARS‐CoV and SARS‐CoV‐2. In line with the absence of detectable ACE2 receptor expression, human PBMCs were refractory to productive infection. RT–PCR experiments and single‐cell RNA sequencing revealed JAK/STAT‐dependent induction of interferon‐stimulated genes (ISGs) but not proinflammatory cytokines. This SARS‐CoV‐2‐specific response was most pronounced in monocytes. SARS‐CoV‐2‐RNA‐positive monocytes displayed a lower ISG signature as compared to bystander cells of the identical culture. This suggests a preferential invasion of cells with a low ISG baseline profile or delivery of a SARS‐CoV‐2‐specific sensing antagonist upon efficient particle internalization. Together, nonproductive physical interaction of PBMCs with SARS‐CoV‐2‐ and, to a much lesser extent, SARS‐CoV particles stimulate JAK/STAT‐dependent, monocyte‐accentuated innate immune responses that resemble those detected in vivo in patients with mild COVID‐19.

A Population Service Evaluation of the ADHD Pathway of Children and Young People's Services, Malta

Introduction

ADHD is the commonest neurodevelopmental disorder in young people (YP) aged 5–18 years. YP with untreated ADHD are 5 times more likely to develop co-morbid psychiatric disorders.

Objectives

To carry out a population service evaluation of the assessment process and management of YP with ADHD at Child and Young People's Service (CYPS), Malta age 0–16 years for 2014.

Aims

To describe the service input, assessment and treatment of YP attending CYPS and compare to ADHD NICE guidelines 2008.

Methods

All patients diagnosed with ADHD at CYPS throughout 2014 were included. The incidence of YP with ADHD on treatment age 3–16 years in Malta was calculated. Information was collected from; (i) retrospective case file review and (ii) methylphenidate and atomoxetine registry and compared with NICE guidelines.

Results

One hundred and thirty-six YP were diagnosed with ADHD. The minimum 12-month incidence of ADHD on treatment (3–16 years) in Malta was 553 per 100,000. Pre-diagnosis assessments were more frequently performed by other YP services (n = 97, 71.3%, P ≤ 0.01). A psychiatrist or paediatrician confirmed the diagnosis in 113 (83.1%). Sixty-two (45.3%) of YP were prescribed medication, 50 (36.8%) were referred for parental skills course and 55 (40.4%) psychotherapy. Mean waiting time for first appointment was 187.6 days (CI ± 26.9, 0–720), and first specialist review was 301.0 days (CI ± 34.4, 0–800) (1–3).

Conclusions

The incidence for YP (3–16 years) with ADHD on treatment was lower than the US. Since most pre-diagnostic assessments were carried out by other services, this raised the question about the reliability and validity. We recommend a diagnostic MDT meeting following the multimodal assessment to diagnose ADHD. Medication prescribing followed NICE overall, standardising non-pharmacological management is required.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Microfluidic device for circulating tumor cell sorting, characterization, and culture

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Background: Circulating tumor cell (CTC) analysis is a promising approach to further characterize the tumor biology and the metastatic process, but has immediate clinical applications such as early predictive markers of response to chemotherapy. However, the devices that are used currently for CTC detection have a poor sensitivity. Microfluidic techniques offer new exciting perspectives in the field of cell sorting for CTC analysis. Methods: We propose here a new microfluidic system and strategy allowing the sorting of cells, their study by confoncal fluorescent microscopy and/or their subsequent culture. The core of our system is a self-organized array of superparamagnetic particles in a microchannel, allowing for the formation of a perfectly periodic and robust array. The superparamagnetic particles are coated with specific antibodies against surface antigens, in order to capture cells according to specific biomarkers. This original cell-separation microchip was integrated into a fully automated platform combining state-of-the-art microfluidic technologies, microvalves and nanofluidic pneumatic pumps. Results: Using B and T lymphocytes mixtures as a model biological system, the capture yield was better than 90%, and the specificity better than 97%. Captured cells were fully viable and were cultured in situ in the magnetic array. In clinics, immunophenotyping of circulating malignant B cells was performed using fluorescent confocal microscopy, and was successfully compared to flow cytometry data for each sample. Results on breast cancer cells will be presented at the meeting. Conclusions: This new system is a promising approach for efficient CTC sorting, analysis and culture in a completely integrated manner.

No significant financial relationships to disclose.

Biomass selection for optimal anaerobic treatment of olive mill wastewater

This research was conducted to identify the most efficient biomass out of five different types of biomass sources for anaerobic treatment of Olive Mill Wastewater (OMW). This study was first focused on examining the selected biomass in anaerobic batch systems with sodium acetate solutions (control study). Then, the different types of biomass were tested with raw OMW (water-diluted) and with pretreated OMW by coagulation-flocculation using Poly Aluminum Chloride (PACl) combined with hydrated lime (Ca(OH)2). Two types of biomass from wastewater treatment systems of a citrus juice producing company "PriGat" and from a citric acid manufacturing factory "Gadot", were found to be the most efficient sources of microorganisms to anaerobically treat both sodium acetate solution and OMW. Both types of biomass were examined under different concentration ranges (1-40 g l(-1)) of OMW in order to detect the maximal COD tolerance for the microorganisms. The results show that 70-85% of COD removal was reached using Gadot biomass after 8-10 days when the initial concentration of OMW was up to 5 g l(-1), while a similar removal efficiency was achieved using OMW of initial COD concentration of 10 g l(-1) in 2-4 days of contact time with the PriGat biomass. The physico-chemical pretreatment of OMW was found to enhance the anaerobic activity for the treatment of OMW with initial concentration of 20 g l(-1) using PriGat biomass. This finding is attributed to reducing the concentrations of polyphenols and other toxicants originally present in OMW upon the applied pretreatment process.