Our lab succesfully generated an iPSC line from a patient suffering from Marfan syndrome (carrying a heterozygous c.7754T>C variant in FBN1). Additionally, an isogenic control was generated using CRISPR/Cas9 technology. These iPSCs can be readily differentiated into cell types of interest, such as vascular smooth muscle cells, and cardiomyocytes.
This isogenic pair will help advance fundamental knowledge concerning Marfan Syndrome.
You can access the paper using this link.
The first CorEuStem (European COST action surrounding stem cells) short term scientific mission allowed hands-on training on hPSC culture, primary cells transduction towards pluripotency and small molecule screening using hPSCs.
Karina Goluba, research assistant from University of Latvia, Riga (Latvia) was introduced to the Medical Cell Biology lab run by Professor Jolanda van Hengel, where she learned how to reprogram somatic cells into iPSCs, basic procedures regarding hPSCs maintenance and differentiation.
“Overall, during this mission I learned all the planned methods and fully implemented the goals set at the beginning. I have gained very good experience in working with pluripotent stem cells…and now I can feel confident working with them soon in my PhD work and in other projects. This STMS also helped establish scientific connection between our host institutions.”
Good news! Our paper named Microscopic visualization of Cell-Cell Adhesion Complexes at Micro and Nanoscale was published in Fronties in Cell and Developmental Biology, April 20th 2022.
In this review, we discuss the main light and electron microscopy techniques used to unravel the structure and composition of the three cell-cell contacts in epithelial and endothelial cells. It functions as a guide to pick the appropriate imaging technique(s) for the adhesion complexes of interest. We also point out the latest techniques that have emerged. At the end, we discuss the problems investigators encounter during their cell-cell adhesion research using microscopic techniques.
Read the paper by clicking this link.
We are proud to announce that our co-authored manuscript titled photothermal nanofibres enable safe engineering of therapeutic cells was published on October 21st in Nature Nanotechnology.
This paper showed that cell membrane permeabilization with photothermal nanofibres is a promising concept towards the safe and more efficient production of engineered cells for therapeutic applications, including stem cell or adoptive T cell therapy.
Access the full article by clicking this link.
Our review titled 'Time for rethinking the different Beta actin transgenic mouse models?' has been accepted for publication in the journal 'cytoskeleton'.
The article can be accessed by clicking here.
A short abstract can be found below:
The actin family is crucial for many cellular processes and in mammals muscle and non‐muscle forms exist. The latter group contains cytoplasmic‐β‐actin and cytoplasmic‐γ‐actin, almost identical in amino acid sequence and with a significant functional overlap. We introduce the properties of the Actb gene and mRNA transcript(s) with main focus on the 3′UTR and its unique features, that is, the zipcode and two polyadenylation sites creating transcripts of different lengths. Several transgenic mouse models with a modified Actb locus have been created. Whole body knockouts and, with one exception, insertion models lead to embryonic lethality indicating that the Actb gene or transcripts or translated β‐actin are essential. Tissue specific ablation at later developmental stages lead to no, or mild phenotypes, suggesting that the Actb gene or β‐actin protein is somewhat dispensable. Gene edited Actb mice that produce γ‐actin are viable. This assumes that the nucleotide sequence of Actb is important and not the specific amino acid sequence of the protein it encodes. Upregulation of other actin paralogs was frequently observed upon β‐actin ablation and can also engage in the phenotype. For a better understanding, it will be necessary to analyze in current and future models all relevant actin transcripts and protein levels in a standardized and comprehensive way.
On the 7th of October, our article titled: "Effects of fibrillin mutations on the behavior of heart muscle cells in Marfan syndrome" was published in the journal Scientific Reports, Nature.
The article describes the first in vitro cardiomyocyte model of Marfan Syndrome.
You can access the article for free by clicking here.
A short abstract can be read below:
Marfan syndrome is a systemic disorder caused by defects in fibrillin-1, a matrix protein. Cardiovascular manifestations, particularly in the aorta, are the most life-threatening consequences. Accumulating evidence from patients and mouse models indicates that Marfan syndrome is also causing a primary cardiomyopathy, but little is known about the mechanism. In this study, induced pluripotent stem cells derived from a Marfan syndrome patient were differentiated to heart muscle cells. This provides a unique alternative approach to study Marfan cardiomyopathy. Here we report the first and only cardiac cell culture model for Marfan syndrome, revealing abnormalities in the behavior of Marfan heart muscle cells that are related to matrix defects. Based on these results, we postulate that impaired support from the extracellular environment plays a key role in the improper functioning of heart muscle cells in Marfan syndrome.
We published the following paper: "Liquid marble technology to create cost-effective 3D cardiospheres as a platform for in vitro drug testing and disease modelling." in the journal MethodsX.
Three-dimensional (3D) cell culturing has several advantages over 2D cultures. 3D cell cultures more accurately mimic the in vivo environment, which is vital to obtain reliable results in disease modelling and toxicity testing.
Current methods to achieve multicellular spheroids are expensive, time-consuming and require specialized materials and training. Hydrophobic powders can be used to create a micro environment for cell cultures, which are termed liquid marbles (LM).
In this procedure we describe the first use of the LM technology for 3D culturing in vitro derived human cardiomyocytes which results in the formation of cardiospheres within 24h. The cardiospheres could be used for several in depth and high-throughput analysis.
You can access the article by clicking here.
Bieke Vanslembrouck succesfully obtained her PhD degree on the 7th of May. The title of her dissertation was: Exploring the three dimensional organisation of the murine intercalated disc and unravelling the connection between the intercalated discs and the cytoskeleton of cardiac myocytes.
We wish her the best of luck on her future endeavours in the group of Carolyn Larabell, Lawrence Berkeley National Laboratory.
Robust protocol for feeder-free adaptation of cryopreserved human pluripotent stem cells
On the 29th of october, a new paper was published in 'In Vitro Cellular & Developmental Biology - Animal'. For a link to the article, click here. (note: this is now open access!)
You can find the abstract below.
Human pluripotent stem cells (hPSCs) are conventionally maintained on mouse embryonic fibroblast (MEF) feeder layers. However, downstream applications, such as directed differentiation protocols, are primarily optimized for feeder-free cultures. Therefore, hPSCs must often be adapted to feeder-free conditions. Here we propose a novel feeder-free adaptation protocol using StemFlex medium, which can be directly applied to thawed hPSC lines.
The direct feeder-free adaptation protocol using StemFlex culture medium on Geltrex coating led to robust hPSC cultures in approximately 2 weeks. This approach was tested with three human embryonic stem cell (hESC) lines. All lines were confirmed to be pluripotent, expressing POU5F1, SOX2, and NANOG. No chromosomal imbalances were induced by the feeder-free adaptation.
StemFlex medium enabled the efficient adaptation of hPSCs to feeder-free conditions directly after thawing. This protocol is easy to implement in laboratories that perform feeder-free cultures, allowing more convenient adaptation and more robust expansion of cryopreserved hPSCs, even in cases when sample quality is low or unknown.