Ins(1,4,5)P3 3-kinase-A overexpression induces cytoskeletal reorganization via a kinase-independent mechanism

2008 ◽  
Vol 414 (3) ◽  
pp. 407-417 ◽  
Author(s):  
Sabine Windhorst ◽  
Christine Blechner ◽  
Hong-Ying Lin ◽  
Christian Elling ◽  
Marcus Nalaskowski ◽  
...  

In the present study, effects of increased IP3K-A [Ins(1,4,5)P3 3-kinase-A] expression were analysed. H1299 cells overexpressing IP3K-A formed branching protrusions, and under three-dimensional culture conditions, they exhibited a motile fibroblast-like morphology. They lost the ability to form actin stress fibres and showed increased invasive migration in vitro. Furthermore, expression levels of the mesenchymal marker proteins vimentin and N-cadherin were increased. The enzymatic function of IP3K-A is to phosphorylate the calcium-mobilizing second messenger Ins(1,4,5)P3 to (Ins(1,3,4,5)P4. Accordingly, cells overexpressing IP3K-A showed reduced calcium release and altered concentrations of InsPs, with decreasing concentrations of Ins(1,4,5)P3, InsP6 and Ins(1,2,3,4,5)P5, and increasing concentrations of Ins(1,3,4,5)P4. However, IP3K-A-induced effects on cell morphology do not seem to be dependent on enzyme activity, since a protein devoid of enzyme activity also induced the formation of branching protrusions. Therefore we propose that the morphological changes induced by IP3K-A are mediated by non-enzymatic activities of the protein.

2021 ◽  
Author(s):  
Nicola Elvassore ◽  
Anna Urciuolo ◽  
Giovanni Giobbe ◽  
Yixiao Dong ◽  
Federica Michielin ◽  
...  

Abstract Tissue architecture is a driving force for morphogenetic processes during development as well as for several physiological and regenerative responses. Far from being a passive static environment, tissue architecture is highly dynamic. Hydrogel technology reproduces in vitro geometrical and mechanical constrains that control the three-dimensional self-organization of (3D) organoids and organ-like cultures. This control is restricted to the initial culture conditions and cannot be adapted to the dynamic morphological changes of complex 3D cultures during their developmental trajectory. Here, we developed a method that overcomes this spatiotemporal limit. Using 2P crosslinking approach, high resolution 3D hydrogel structures can be fabricated within pre-existing hydrogel with spatiotemporal (four-dimensional, 4D) control relative to ex-vivo organotypic or organoid culture. This hydrogel-in-hydrogel bioprinting approach enables to continuously instruct the self-organization of the evolving 3D organ-like cultures.


Author(s):  
Yu Takahashi ◽  
Yu Inoue ◽  
Keitaro Kuze ◽  
Shintaro Sato ◽  
Makoto Shimizu ◽  
...  

Abstract Intestinal organoids better represent in vivo intestinal properties than conventionally used established cell lines in vitro. However, they are maintained in three-dimensional culture conditions that may be accompanied by handling complexities. We characterized the properties of human organoid-derived two-dimensionally cultured intestinal epithelial cells (IECs) compared with those of their parental organoids. We found that the expression of several intestinal markers and functional genes were indistinguishable between monolayer IECs and organoids. We further confirmed that their specific ligands equally activate intestinal ligand-activated transcriptional regulators in a dose-dependent manner. The results suggest that culture conditions do not significantly influence the fundamental properties of monolayer IECs originating from organoids, at least from the perspective of gene expression regulation. This will enable their use as novel biological tools to investigate the physiological functions of the human intestine.


2012 ◽  
Vol 24 (1) ◽  
pp. 162
Author(s):  
J. R. Miles ◽  
C. N. Sargus ◽  
S. A. Plautz ◽  
J. L. Vallet ◽  
A. K. Pannier

Between Day 10 and 12 of gestation, the pig embryo elongates from a sphere to a long thin, filament. During this time, the embryo increases the production of oestrogen via an increase in steroidogenic transcripts, which is critical for maternal recognition of pregnancy. To date, attempts to elongate porcine embryos in vitro have been unsuccessful. Therefore, the objective of this study was to utilise alginate hydrogels to establish a culture system that promotes in vitro embryo elongation with a corresponding increase in steroidogenic transcripts and oestradiol production. In 3 replicate collections, White crossbred gilts (n = 15) were bred at Day 0 of the oestrous cycle. At Day 9 of gestation, reproductive tracts were collected and flushed with RPMI-1640 containing antibiotics. Embryos were recovered, grouped according to size and washed with RPMI-1640 containing antibiotics and 10% fetal bovine serum (FBS). Embryos were randomly assigned to be encapsulated using a double encapsulation technique (0.7% sodium alginate and 1.5% calcium chloride solution) or used as controls. Encapsulated and control embryos were cultured for 96 h in CO2 -pretreated RPMI-1640 containing antibiotics and 10% FBS at 38°C, 5% CO2 in air and 100% humidity. Every 24 h, the embryos were imaged and half of the media was replaced. The removed media was stored at –20°C and used to assess oestradiol levels by radioimmunoassay. At the end of culture, a subset of encapsulated and control embryos were snap frozen and used to assess the expression level of steroidogenic transcripts (STAR, CYP11 and CYP19) using quantitative PCR. All data were analysed using general linear model (GLM) procedures for ANOVA. Cell survival, assessed by blastocyst fragmentation and confirmed by live/dead staining in representative embryos, was greater (P = 0.01) for encapsulated embryos (60.1 ± 4.8%) compared with controls (33.3 ± 4.8%). Of encapsulated embryos, 27% had some morphological change (minor flattening and tubal formation) and 14% had significant morphological changes (considerable flattening and tubal formation elongating through the gel), consistent with in vivo embryo elongation. In contrast, the control embryos had no morphological changes observed and remained spherical during culture. The expression levels of STAR, CYP11 and CYP19 were significantly (P < 0.05) greater in encapsulated embryos compared with control embryos. Furthermore, a significant (P < 0.01) time-dependent increase in oestradiol levels in the culture media of encapsulated embryos was identified compared with controls and culture media alone. These results illustrate that cultured pig embryos encapsulated in alginate hydrogels undergo limited morphological changes with increased expression of steroidogenic transcripts and oestrogen production. †USDA is an equal opportunity provider and employer.


2016 ◽  
Vol 21 (8) ◽  
pp. 804-815 ◽  
Author(s):  
X. Medda ◽  
L. Mertens ◽  
S. Versweyveld ◽  
A. Diels ◽  
L. Barnham ◽  
...  

Tau aggregation is the pathological hallmark that best correlates with the progression of Alzheimer’s disease (AD). The presence of neurofibrillary tangles (NFTs), formed of hyperphosphorylated tau, leads to neuronal dysfunction and loss, and is directly associated with the cognitive decline observed in AD patients. The limited success in targeting β-amyloid pathologies has reinforced the hypothesis of blocking tau phosphorylation, aggregation, and/or spreading as alternative therapeutic entry points to treat AD. Identification of novel therapies requires disease-relevant and scalable assays capable of reproducing key features of the pathology in an in vitro setting. Here we use induced pluripotent stem cells (iPSCs) as a virtually unlimited source of human cortical neurons to develop a robust and scalable tau aggregation model compatible with high-throughput screening (HTS). We downscaled cell culture conditions to 384-well plate format and used Matrigel to introduce an extra physical protection against cell detachment that reduces shearing stress and better recapitulates pathological conditions. We complemented the assay with AlphaLISA technology for the detection of tau aggregates in a high-throughput-compatible format. The assay is reproducible across users and works with different commercially available iPSC lines, representing a highly translational tool for the identification of novel treatments against tauopathies, including AD.


2010 ◽  
Vol 638-642 ◽  
pp. 506-511 ◽  
Author(s):  
Claudia Bergemann ◽  
Ernst Dieter Klinkenberg ◽  
Frank Lüthen ◽  
Arne Weidmann ◽  
Regina Lange ◽  
...  

Porous tantalum (Ta) biomaterial is designed to function as a scaffold for osseous ingrowths and has found applications in orthopedics. Integration of this Ta foam into the neighboring bone requires that osteoprogenitor cells attach to the implant, grow into the scaffold, proliferate and differentiate to osteoblasts. The aim of the present study was to create an in vitro 3D model system to investigate the interaction of human osteoblasts with porous Ta in the depth of the corpus. To explore active migration of osteoblasts into the Ta scaffold two porous Ta discs (Zimmer, Poland) were horizontally fixed within a clamping ring. Thereby a 3D Ta module with 4 levels is generated, which is placed into a cell culture well with the appropriate medium. Osteoblast-like cells were seeded apical onto the Ta module and cultured for 7 days in humidified atmosphere. Active migration of cells into the scaffold was monitored by field emission scanning electron microscopy (FESEM) imaging of the apical, medial and basal layers. A problem in 3D cell culture is the nutrition of cells inside of the scaffold. Therefore morphological changes and differentiation of the cells in distinct layers were analyzed.


2013 ◽  
Vol 67 (4) ◽  
pp. 863-868 ◽  
Author(s):  
T. M. Straub ◽  
J. R. Hutchison ◽  
R. A. Bartholomew ◽  
C. O. Valdez ◽  
N. B. Valentine ◽  
...  

Significant difficulties remain for determining whether human noroviruses (hNoV) recovered from water, food, and environmental samples are infectious. Three-dimensional (3-D) tissue culture of human intestinal cells has shown promise in developing an infectivity assay, but reproducibility, even within a single laboratory, remains problematic. From the literature and our observations, we hypothesized that the common factors that lead to more reproducible hNoV infectivity in vitro requires that the cell line be (1) of human gastrointestinal origin, (2) expresses apical microvilli, and (3) be a positive secretor cell line. The C2BBe1 cell line, which is a brush-border producing clone of Caco-2, meets these three criteria. When challenged with Genogroup II viruses, we observed a 2 Log10 increase in viral RNA titer. A passage experiment with GII viruses showed evidence of the ability to propagate hNoV by both quantitative reverse transcription polymerase chain reaction (qRT-PCR) and microscopy. In our hands, using 3-D C2BBe1 cells improves reproducibility of the infectivity assay for hNoV, but the assay can still be variable. Two sources of variability include the cells themselves (mixed phenotypes of small and large intestine) and initial titer measurements using qRT-PCR that measures all RNA vs. plaque assays that measure infectious virus.


2022 ◽  
Vol 2 (1) ◽  
pp. 10-27
Author(s):  
Deepankar Chakroborty ◽  
Veera K. Ojala ◽  
Anna M. Knittle ◽  
Jasmin Drexler ◽  
Mahlet Z. Tamirat ◽  
...  

Despite the relatively high frequency of somatic ERBB4 mutations in various cancer types, only a few activating ERBB4 mutations have been characterized, primarily due to lack of mutational hotspots in the ERBB4 gene. Here, we utilized our previously published pipeline, an in vitro screen for activating mutations, to perform an unbiased functional screen to identify potential activating ERBB4 mutations from a randomly mutated ERBB4 expression library. Ten potentially activating ERBB4 mutations were identified and subjected to validation by functional and structural analyses. Two of the 10 ERBB4 mutants, E715K and R687K, demonstrated hyperactivity in all tested cell models and promoted cellular growth under two-dimensional and three-dimensional culture conditions. ERBB4 E715K also promoted tumor growth in in vivo Ba/F3 cell mouse allografts. Importantly, all tested ERBB4 mutants were sensitive to the pan-ERBB tyrosine kinase inhibitors afatinib, neratinib, and dacomitinib. Our data indicate that rare ERBB4 mutations are potential candidates for ERBB4-targeted therapy with pan-ERBB inhibitors. Statement of Significance: ERBB4 is a member of the ERBB family of oncogenes that is frequently mutated in different cancer types but the functional impact of its somatic mutations remains unknown. Here, we have analyzed the function of over 8,000 randomly mutated ERBB4 variants in an unbiased functional genetics screen. The data indicate the presence of rare activating ERBB4 mutations in cancer, with potential to be targeted with clinically approved pan-ERBB inhibitors.


2021 ◽  
Author(s):  
R. Hugh F. Bender ◽  
Benjamen T O'Donnell ◽  
Bhupinder Shergill ◽  
Brittany Q Pham ◽  
Damie J Juat ◽  
...  

Insulin is an essential regulator of blood glucose homeostasis that is produced exclusively by β cells within the pancreatic islets of healthy individuals. In those affected by diabetes, immune inflammation, damage, and destruction of islet β cells leads to insulin deficiency and hyperglycemia. Current efforts to understand the mechanisms underlying β cell damage in diabetes rely on in vitro-cultured cadaveric islets. However, isolation of these islets involves removal of crucial matrix and vasculature that supports islets in the intact pancreas. Unsurprisingly, these islets demonstrate reduced functionality over time in standard culture conditions, thereby limiting their value for understanding native islet biology. Leveraging a novel, vascularized micro-organ (VMO) approach, we have recapitulated elements of the native pancreas by incorporating isolated human islets within a three-dimensional matrix nourished by living, perfusable blood vessels. Importantly, these islets show long-term viability and maintain robust glucose-stimulated insulin responses. Furthermore, vessel-mediated delivery of immune cells to these tissues provides a model to assess islet-immune cell interactions and subsequent islet killing -- key steps in type 1 diabetes pathogenesis. Together, these results establish the islet-VMO as a novel, ex vivo platform for studying human islet biology in both health and disease.


2021 ◽  
Author(s):  
Philippe J.R. Cohen ◽  
Elisa Luquet ◽  
Justine Pletenka ◽  
Andrea Leonard ◽  
Elise Warter ◽  
...  

Human pluripotent stem cells (hPSCs) have emerged as the most promising cellular source for cell therapies. To overcome scale up limitations of classical 2D culture systems, suspension cultures have been developed to meet the need of large-scale culture in regenerative medicine. Despite constant improvements, current protocols relying on the generation of micro-carriers or cell aggregates only achieve moderate amplification performance. Here, guided by reports showing that hPSCs can self-organize in vitro into cysts reminiscent of the epiblast stage in embryo development, we developed a physio-mimetic approach for hPSC culture. We engineered stem cell niche microenvironments inside microfluidics-assisted core-shell microcapsules. We demonstrate that lumenized three-dimensional colonies maximize viability and expansion rates while maintaining pluripotency. By optimizing capsule size and culture conditions, we scale-up this method to industrial scale stirred tank bioreactors and achieve an unprecedented hPSC amplification rate of 282-fold in 6.5 days.


2016 ◽  
Vol 4 (2) ◽  
pp. 65
Author(s):  
Ika Roostika ◽  
Ragapadmi Purnamaningsih ◽  
Arief V. Noviati

<p>Pruatjan (Pimpinella pruatjan Molk.) is an Indonesian<br />medicinal plant which is categorized as endangered<br />plant and included in Appendix I based on CITES. The in<br />vitro conservation techniques have been studied. However,<br />the storage period was very short (4 months) when plant<br />growth retardant and media dilution were applied. Beside<br />that, the residual effect of growth retardant was strong<br />enough so that it needed more than 4 months for recovery.<br />Thus, the use of certain carbon source may prolong the<br />preservation period with shorter time for recovery. The<br />objective of the study was to know the effects of carbon<br />sources (sucrose and mannitol) and culture conditions (culture<br />room and growth chamber) to the growth of pruatjan<br />cultures. This application was hoped to prolong preservation<br />period of pruatjan longer than 4 months and to cut the<br />recovery period after presservation. The study was conducted<br />at Tissue Culture Laboratory in Indonesian Center for<br />Agricultural Biotechnology and Genetic Resources Research<br />and Development from August 2006 to July 2007. The<br />activities included propagation of in vitro shoot grown in<br />vitro as explants source, preservation of in vitro shoots of<br />pruatjan, and regeneration of the cultures after preservation.<br />The experiment was designed as factorial in Randomized<br />Completely Block Design with 6 replications. The DKW basal<br />media containing 1 ppm BA, 0.2 ppm thidiazuron, and 100<br />ppm arginine were supplemented with mannitol or sucrose<br />at the level of 1, 2, 3, 4, and 5%. The observed variables were<br />total number of leaves, number of shoot, and number of wilt<br />leaves. The result revealed that pruatjan cultures could be<br />stored longer than 4 months. Generally, the effect of<br />mannitol or sucrose was more dominant than that of cultures<br />condition. The mannitol (1-5%) strongly inhibited the<br />growth of pruatjan cultures so that only a few cultures<br />survived at 7 months preservation period and needed about<br />1 month for recovery. On the contrary, the effect of sucrose<br />(at the same level) was better than mannitol. The 2.5%<br />sucrose optimally inhibited pruatjan cultures. At that condition,<br />the cultures could be stored for 10 months without<br />morphological changes so that they could recover spontaneously.</p>


Sign in / Sign up

Export Citation Format

Share Document