Cell Cluster Sorting in Automated Differentiation of Patient-specific Induced Pluripotent Stem Cells Towards Blood Cells.

Induced pluripotent stem cells (iPS cells) represent a particularly versatile stem cell type for a large array of applications in biology and medicine. Taking full advantage of iPS cell technology requires high throughput and automated iPS cell culture and differentiation. We present an automated platform for efficient and robust iPS cell culture and differentiation into blood cells. We implemented cell cluster sorting for analysis and sorting of iPS cell clusters in order to establish clonal iPS cell lines with high reproducibility and efficacy. Patient-specific iPS cells were induced to differentiate towards hematopoietic cells via embryoid body (EB) formation. EB size impacts on iPS cell differentiation and we applied cell cluster sorting to obtain EB of defined size for efficient blood cell differentiation. In summary, implementing cell cluster sorting into the workflow of iPS cell cloning, growth and differentiation represent a valuable add-on for standard and automated iPS cell handling.

A multicentre interventional study to assess blood-borne viral infections in Belgian prisons.

BACKGROUND: Prevalence data on viral hepatitis B (HBV), hepatitis C (HCV), and HIV infection in prison are often scarce or outdated. There is currently no systematic screening for these blood-borne viral infections (BBV) in Belgian prisons. There is an urgency to assess the prevalence of these BBV to inform policymakers and public healthcare. METHODS: This was a multicentre, interventional study to assess the prevalence of BBV using opt-in screening in prisons across Belgium, April 2019 - March 2020. Prisoners were tested using a finger prick and BBV risk factors were assessed using a questionnaire. A generalized linear mixed model was used to investigate the association between the various risk factors and HCV. RESULTS: In total, 886 prisoners from 11 Belgian prisons were screened. Study uptake ranged from 16.9 to 35.4% in long-term facilities. The prevalence of HCV antibodies (Ab), hepatitis B surface antigen (Ag) and HIV Ab/Ag was 5.0% (44/886), 0.8% (7/886), and 0.2% (2/886). The adjusted odds for HCV Ab were highest in prisoners who ever injected (p < 0.001; AOR 24.6 CI 95% (5.5-215.2). The prevalence of detectable HCV RNA in the total cohort was 2.1% (19/886). Thirteen (68.4%) prisoners were redirected for follow-up of their HCV infection. CONCLUSIONS: Opt-in testing for viral hepatitis B, C and HIV was relatively well-accepted in prisons. Compared with the general population, prisoners have a higher prevalence of infection with BBV, especially for HCV. Systematic screening for these BBV should be recommended in all prisons, preferably using opt-out to optimize screening uptake. TRIAL REGISTRATION: Retrospectively registered at clinical trials NCT04366492 April 29, 2020.

Flow cytometry of microencapsulated colonies for genetics analysis of filamentous fungi.

The analysis of filamentous fungi by flow cytometry has been impossible to date due to their filamentous nature and size. In this work, we have developed a method that combines single-spore microencapsulation and large-particle flow cytometry as a powerful alternative for the genetic analysis of filamentous fungi. Individual spores were embedded in monodisperse alginate microparticles and incubated in the appropriate conditions. Growth could be monitored by light or fluorescent microscopy and Complex Object Parametric Analyzer and Sorter large-particle flow cytometry. Microencapsulated Trichoderma and Aspergillus spores could germinate and grow inside the alginate capsules. Growth tests revealed that auxotrophic mutants required the appropriate nutrients and that pyrithiamine and glufosinate halted fungal growth of sensitive but not resistant strains. We used an Aspergillus nidulans, thermosensitive mutant in the cell-cycle regulator gene nimX(CDK1) as proof-of-concept to the detection and identification of genetic phenotypes. Sorting of the microparticles containing the clonal fungal mycelia proved the power of this method to perform positive and/or negative selection during genetic screenings.