An Evaluation of the Replacement of Animal-derived Biomaterials in Human Primary Cell Culture.

The likelihood that potential new drugs will successfully navigate the current translational pipeline is poor, with fewer than 10% of drug candidates making this transition successfully, even after their entry into clinical trials. Prior to this stage, candidate drugs are typically evaluated by using models of increasing complexity, beginning with basic in vitro cell culture studies and progressing through to animal studies, where many of these candidates are lost due to lack of efficacy or toxicology concerns. There are many reasons for this poor translation, but interspecies differences in functional and physiological parameters undoubtedly contribute to the problem. Improving the human-relevance of early preclinical in vitro models may help translatability, especially when targeting more nuanced species-specific cell processes. The aim of the current study was to define a set of guidelines for the effective transition of human primary cells of multiple lineages to more physiologically relevant, translatable, animal-free in vitro culture conditions. Animal-derived biomaterials (ADBs) were systematically replaced with non-animal-derived alternatives in the in vitro cell culture systems, and the impact of the substitutions subsequently assessed by comparing the kinetics and phenotypes of the cultured cells. ADBs were successfully eliminated from primary human dermal fibroblast, uterine fibroblast, pulmonary fibroblast, retinal endothelial cell and peripheral blood mononuclear cell culture systems, and the individual requirements of each cell subtype were defined to ensure the successful transition toward growth under animal-free culture conditions. We demonstrate that it is possible to transition ('humanise') a diverse set of human primary cell types by following a set of simple overarching principles that inform the selection, and guide the evaluation of new, improved, human-relevant in vitro culture conditions.

Vaccine escape, increased breakthrough and reinfection in infliximab-treated patients with IBD during the Omicron wave of the SARS-CoV-2 pandemic.

OBJECTIVE: Antitumour necrosis factor (TNF) drugs impair serological responses following SARS-CoV-2 vaccination. We sought to assess if a third dose of a messenger RNA (mRNA)-based vaccine substantially boosted anti-SARS-CoV-2 antibody responses and protective immunity in infliximab-treated patients with IBD. DESIGN: Third dose vaccine induced anti-SARS-CoV-2 spike (anti-S) receptor-binding domain (RBD) antibody responses, breakthrough SARS-CoV-2 infection, reinfection and persistent oropharyngeal carriage in patients with IBD treated with infliximab were compared with a reference cohort treated with vedolizumab from the impaCt of bioLogic therApy on saRs-cov-2 Infection and immuniTY (CLARITY) IBD study. RESULTS: Geometric mean (SD) anti-S RBD antibody concentrations increased in both groups following a third dose of an mRNA-based vaccine. However, concentrations were lower in patients treated with infliximab than vedolizumab, irrespective of whether their first two primary vaccine doses were ChAdOx1 nCoV-19 (1856 U/mL (5.2) vs 10 728 U/mL (3.1), p<0.0001) or BNT162b2 vaccines (2164 U/mL (4.1) vs 15 116 U/mL (3.4), p<0.0001). However, no differences in anti-S RBD antibody concentrations were seen following third and fourth doses of an mRNA-based vaccine, irrespective of the combination of primary vaccinations received. Post-third dose, anti-S RBD antibody half-life estimates were shorter in infliximab-treated than vedolizumab-treated patients (37.0 days (95% CI 35.6 to 38.6) vs 52.0 days (95% CI 49.0 to 55.4), p<0.0001).Compared with vedolizumab-treated, infliximab-treated patients were more likely to experience SARS-CoV-2 breakthrough infection (HR 2.23 (95% CI 1.46 to 3.38), p=0.00018) and reinfection (HR 2.10 (95% CI 1.31 to 3.35), p=0.0019), but this effect was uncoupled from third vaccine dose anti-S RBD antibody concentrations. Reinfection occurred predominantly during the Omicron wave and was predicted by SARS-CoV-2 antinucleocapsid concentrations after the initial infection. We did not observe persistent oropharyngeal carriage of SARS-CoV-2. Hospitalisations and deaths were uncommon in both groups. CONCLUSIONS: Following a third dose of an mRNA-based vaccine, infliximab was associated with attenuated serological responses and more SARS-CoV-2 breakthrough infection and reinfection which were not predicted by the magnitude of anti-S RBD responses, indicative of vaccine escape by the Omicron variant. TRIAL REGISTRATION NUMBER: ISRCTN45176516.

Corrigendum: Ceremonial ayahuasca in amazonian retreats-mental health and epigenetic outcomes from a six-month naturalistic study.

[This corrects the article DOI: 10.3389/fpsyt.2021.687615.].

Persistence of clinically relevant levels of SARS-CoV2 envelope gene subgenomic RNAs in non-immunocompromised individuals.

OBJECTIVES: This study aimed to evaluate the associations between COVID-19 severity and active viral load, and to characterize the dynamics of active SARS-CoV-2 clearance in a series of archival samples taken from patients in the first wave of COVID-19 infection in the South West of the UK. METHODS: Subgenomic RNA (sgRNA) and E-gene genomic sequences were measured in a retrospective collection of PCR-confirmed SARS-CoV-2-positive samples from 176 individuals, and related to disease severity. Viral clearance dynamics were then assessed in relation to symptom onset and last positive test. RESULTS: Whilst E-gene sgRNAs declined before E-gene genomic sequences, some individuals retained sgRNA positivity for up to 68 days. 13% of sgRNA-positive cases still exhibited clinically relevant levels of virus after 10 days, with no clinical features previously associated with prolonged viral clearance times. CONCLUSIONS: Our results suggest that potentially active virus can sometimes persist beyond a 10-day period, and could pose a potential risk of onward transmission. Where this would pose a serious public health threat, additional mitigation strategies may be necessary to reduce the risk of secondary cases in vulnerable settings.

Ceremonial Ayahuasca in Amazonian Retreats-Mental Health and Epigenetic Outcomes From a Six-Month Naturalistic Study.

Ayahuasca is a natural psychoactive brew, used in traditional ceremonies in the Amazon basin. Recent research has indicated that ayahuasca is pharmacologically safe and its use may be positively associated with improvements in psychiatric symptoms. The mechanistic effects of ayahuasca are yet to be fully established. In this prospective naturalistic study, 63 self-selected participants took part in ayahuasca ceremonies at a retreat centre in the Peruvian Amazon. Participants undertook the Beck Depression Inventory (BDI-II), State-Trait Anxiety Inventory (STAI), Self-compassion Scale (SCS), Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM), as well as secondary measures, pre- and post-retreat and at 6-months. Participants also provided saliva samples for pre/post epigenetic analysis. Overall, a statistically significant decrease in BDI-II (13.9 vs. 6.1, p < 0.001), STAI (44.4 vs. 34.3 p < 0.001) scores, and CORE-OM scores were observed (37.3 vs. 22.3 p < 0.001) at post-retreat, as well as a concurrent increase in SCS (3.1 vs. 3.6, p < 0.001). Psychometric improvements were sustained, and on some measures values further decreased at 6-month follow-up, suggesting a potential for lasting therapeutic effects. Changes in memory valence were linked to the observed psychometric improvements. Epigenetic findings were equivocal, but indicated that further research in candidate genes, such as sigma non-opioid intracellular receptor 1 (SIGMAR1), is warranted. This data adds to the literature supporting ayahuasca's possible positive impact on mental health when conducted in a ceremonial context. Further investigation into clinical samples, as well as greater analyses into the mechanistic action of ayahuasca is advised.