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Biology subjects

Tan, J. P.

Publications and source records attributed to Tan, J. P..

4 recordsLinked to original sources

Rising together: Exploring Sourdough Fermentation Diversity through Co-design in the HealthFerm Citizen Science Initiative

Fermented foods are culturally significant and increasingly recognized for their potential health benefits, yet scientific data on household fermentation practices remain limited. We launched a co-designed citizen science (CS) initiative within the HealthFerm project to collect sourdough fermentation data across Europe. Over 1000 participants from 33 countries registered, with 671 samples submitted, enabling large-scale analysis of fermentation practices, motivations, and sourdough characteristics. Participants also completed standardized at-home experiments and sensory evaluations, generating a dataset linking baking habits with physicochemical and sensory profiles. Distinct patterns emerged: professional bakers used older, more frequently refreshed starters and fermented at higher temperatures. Ingredient choices and motivations varied by country, shaped by perceived health benefits. Beyond data collection, this initiative established a microbial biobank and harmonized metadata resource, while offering practical insights into co- design, logistics, and public engagement. The resulting framework provides a transferable model for participatory research in microbiology and food systems science.

scientific communication and education↗

Transient Naive Treatment (TNT) iPS cells do not feature Sendai virus expression: Response to Sendai virus persistence questions the transient naive reprogramming method for iPSC generation

SummaryThe Transient Naive Treatment (TNT) reprogramming method involves a brief period of culturing in naive media early in the reprogramming process. Through conducting extensive molecular, epigenetic, and functional analyses on numerous induced pluripotent stem cell lines, we have demonstrated that TNT reprogramming facilitates epigenetic memory erasure and produces induced pluripotent stem (iPS) cells more similar to embryonic stem (ES) cells than conventional reprogramming methods1. In 2024, De Los Angeles et al. posted a contradictory results preprint on bioRxiv titled Sendai virus persistence questions the transient naive reprogramming method for iPSC generation2. Their claims include: 1) that Sendai virus expression in naive cultured cells questions the TNT reprogramming method, 2) the possible selection of cells (clonal expansion) with Sendai virus expression during TNT reprogramming, 3) Sendai virus genes being expressed in control samples implying a potential sample mix-up. Here, we demonstrate these claims are not directly supported by the data, and emphasize that we assessed the possibility of cell sub-population selection experimentally in Buckberry et al. (2023). Moreover, our re-analyses of the data in the context of Sendai virus expression during reprogramming actually highlight the advantages of TNT reprogramming concerning the timing of the naive media treatment and the absence of detectable Sendai virus gene expression.

developmental biology↗

Parallel use of pluripotent human stem cell lung and heart models provide new insights for treatment of SARS-CoV-2

SARS-CoV-2 primarily infects the respiratory tract, but pulmonary and cardiac complications occur in severe COVID-19. To elucidate molecular mechanisms in the lung and heart, we conducted paired experiments in human stem cell-derived lung alveolar type II (AT2) epithelial cell and cardiac cultures infected with SARS-CoV-2. With CRISPR- Cas9 mediated knock-out of ACE2, we demonstrated that angiotensin converting enzyme 2 (ACE2) was essential for SARS-CoV-2 infection of both cell types but further processing in lung cells required TMPRSS2 while cardiac cells required the endosomal pathway. Host responses were significantly different; transcriptome profiling and phosphoproteomics responses depended strongly on the cell type. We identified several antiviral compounds with distinct antiviral and toxicity profiles in lung AT2 and cardiac cells, highlighting the importance of using several relevant cell types for evaluation of antiviral drugs. Our data provide new insights into rational drug combinations for effective treatment of a virus that affects multiple organ systems. One-sentence summaryRational treatment strategies for SARS-CoV-2 derived from human PSC models

microbiology↗

An iTSC-derived placental model of SARS-CoV-2 infection unveils ACE2-dependent susceptibility in syncytiotrophoblasts

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causing coronavirus disease 2019 (COVID-19) has caused a global health crisis. The primary site of infection is in the respiratory tract but the virus has been associated with a variety of complications involving the gastrointestinal and cardiovascular systems. Since the virus affects a variety of tissue types, there has been interest in understanding SARS-CoV-2 infection in early development and the placenta. ACE2 and TMPRSS2, two genes that are critical for SARS-CoV-2 virus entry are expressed in placenta-specific cell types including extravillous trophoblasts (EVTs) and especially, syncytiotrophoblasts (STs). The potential of SARS-CoV-2 to infect these placental cells and its effect on placental development and function is still unclear. Furthermore, it is crucial to understand the possible mechanism of vertical transmission of SARS-CoV-2 through the placenta. Here, we developed an in vitro model of SARS-CoV-2 infection of placental cell types using induced trophoblast stem cells (iTSCs). This model allowed us to show that STs but not EVTs are infected. Importantly, infected STs lack the expression of key differentiation genes, lack typically observed differentiated morphology and produce significantly lower human chorionic gonadotropin (HCG) compared to non-infected controls. We also show that an anti-ACE2 antibody prevents SARS-CoV-2 infection and restores normal ST differentiation and function. We highlight the establishment of a platform to study SARS-CoV-2 infection in early placental cell types, which will facilitate investigation of antiviral therapy to protect the placenta during early pregnancy and development.

cell biology↗