scholarly journals Development, characterization, and applications of multi-material stereolithography bioprinting

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bagrat Grigoryan ◽  
Daniel W. Sazer ◽  
Amanda Avila ◽  
Jacob L. Albritton ◽  
Aparna Padhye ◽  
...  

AbstractAs a 3D bioprinting technique, hydrogel stereolithography has historically been limited in its ability to capture the spatial heterogeneity that permeates mammalian tissues and dictates structure–function relationships. This limitation stems directly from the difficulty of preventing unwanted material mixing when switching between different liquid bioinks. Accordingly, we present the development, characterization, and application of a multi-material stereolithography bioprinter that provides controlled material selection, yields precise regional feature alignment, and minimizes bioink mixing. Fluorescent tracers were first used to highlight the broad design freedoms afforded by this fabrication strategy, complemented by morphometric image analysis to validate architectural fidelity. To evaluate the bioactivity of printed gels, 344SQ lung adenocarcinoma cells were printed in a 3D core/shell architecture. These cells exhibited native phenotypic behavior as evidenced by apparent proliferation and formation of spherical multicellular aggregates. Cells were also printed as pre-formed multicellular aggregates, which appropriately developed invasive protrusions in response to hTGF-β1. Finally, we constructed a simplified model of intratumoral heterogeneity with two separate sub-populations of 344SQ cells, which together grew over 14 days to form a dense regional interface. Together, these studies highlight the potential of multi-material stereolithography to probe heterotypic interactions between distinct cell types in tissue-specific microenvironments.


Author(s):  
Eva Bartova ◽  
Sona Legartova ◽  
Jana Krejci ◽  
Orazio A. Arcidiacono

Abstract Angiotensin-converting enzyme (ACE) is a zinc metalloproteinase involved in the renin-angiotensin system (RAS). It is well known that ACE and ACE2 are central regulators of blood pressure. Moreover, recently, it was observed that the ACE2 protein is the main target of the SARS-CoV-2 virus, so we have tried to reveal if there is a distinction in the levels of the ACE2 protein in distinct cell types (sensitive to virus infection), during cell differentiation and aging. We observed that depletion of the ACE2 protein appears in aorta-associated parts during the aging of adult mice, and the level of ACE2 was lowest in kidneys of old female animals in comparison to male mice. Differentiation into enterocytes and more pronouncedly into cardiomyocytes was accompanied by depletion of the ACE2 protein. The deficiency of histone deacetylase 1 (HDAC1) also caused a decrease in the level of both ACE2 and its interacting partner renin. However, experimental cardiomyogenesis was associated with renin up-regulation. In human lung adenocarcinoma cells, vitamin D2, but not chloroquine, slightly increased the level of ACE2. Together, the higher level of the ACE2 protein appears in non-differentiated cells and tissue of young mice, in comparisons to terminally differentiated cells and old animals; thus, a higher level of the ACE2 protein, also seen after vitamin D2 treatment, seems to be a barrier against SARS-CoV-2, because it is known that tissues of young individuals are less sensitive to viral infection.



Author(s):  
Brendan Clifford

An ultrastructural investigation of the Malpighian tubules of the fourth instar larva of Culex pipiens was undertaken as part of a continuing study of the fine structure of transport epithelia.Each of the five Malpighian tubules was found to be morphologically identical and regionally undifferentiated. Two distinct cell types, the primary and stellate, were found intermingled along the length of each tubule. The ultrastructure of the stellate cell was previously described in the Malpighian tubule of the blowfly, Calliphora erythrocephala by Berridge and Oschman.The basal plasma membrane of the primary cell is extremely irregular, giving rise to a complex interconnecting network of basal channels. The compartments of cytoplasm entrapped within this system of basal infoldings contain mitochondria, free ribosomes, and small amounts of rough endoplasmic reticulum. The mitochondria are distinctive in that the cristae run parallel to the long axis of the organelle.



2021 ◽  
Vol 22 (9) ◽  
pp. 4960
Author(s):  
Natalia Guillén Díaz-Maroto ◽  
Gemma Garcia-Vicién ◽  
Giovanna Polcaro ◽  
María Bañuls ◽  
Nerea Albert ◽  
...  

Heterotypic interactions between newly transformed cells and normal surrounding cells define tumor’s fate in incipient carcinomas. Once homeostasis has been lost, normal resident fibroblasts become carcinoma-associated fibroblasts, conferring protumorogenic properties on these normal cells. Here we describe the IL1β-mediated interplay between cancer cells and normal colonic myofibroblasts (NCFs), which bestows differential sensitivity to cytotoxic drugs on tumor cells. We used NCFs, their conditioned media (CM), and cocultures with tumor cells to characterize the IL1β-mediated crosstalk between both cell types. We silenced IL1β in tumor cells to demonstrate that such cells do not exert an influence on NCFs inflammatory phenotype. Our results shows that IL1β is overexpressed in cocultured tumor cells. IL1β enables paracrine signaling in myofibroblasts, converting them into inflammatory-CAFs (iCAF). IL1β-stimulated-NCF-CM induces migration and differential sensitivity to oxaliplatin in colorectal tumor cells. Such chemoprotective effect has not been evidenced for TGFβ1-driven NCFs. IL1β induces the loss of a myofibroblastic phenotype in NCFs and acquisition of iCAF traits. In conclusion, IL1β-secreted by cancer cells modify surrounding normal fibroblasts to confer protumorogenic features on them, particularly tolerance to cytotoxic drugs. The use of IL1β-blocking agents might help to avoid the iCAF traits acquisition and consequently to counteract the protumorogenic actions these cells.



Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 355
Author(s):  
Guilhem Lalle ◽  
Julie Twardowski ◽  
Yenkel Grinberg-Bleyer

The emergence of immunotherapies has definitely proven the tight relationship between malignant and immune cells, its impact on cancer outcome and its therapeutic potential. In this context, it is undoubtedly critical to decipher the transcriptional regulation of these complex interactions. Following early observations demonstrating the roles of NF-κB in cancer initiation and progression, a series of studies converge to establish NF-κB as a master regulator of immune responses to cancer. Importantly, NF-κB is a family of transcriptional activators and repressors that can act at different stages of cancer immunity. In this review, we provide an overview of the selective cell-intrinsic contributions of NF-κB to the distinct cell types that compose the tumor immune environment. We also propose a new view of NF-κB targeting drugs as a new class of immunotherapies for cancer.



2021 ◽  
Vol 22 (7) ◽  
pp. 3649
Author(s):  
Patricia Ramos-Ramírez ◽  
Omar Tliba

Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRβ, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRβ has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRβ actions are restricted to its dominant-negative effects on GRα-mediated responses, GRβ has been shown to have intrinsic activities and “directly” regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRβ has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRβ-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRβ and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.



2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Arjan van der Velde ◽  
Kaili Fan ◽  
Junko Tsuji ◽  
Jill E. Moore ◽  
Michael J. Purcaro ◽  
...  

AbstractThe morphologically and functionally distinct cell types of a multicellular organism are maintained by their unique epigenomes and gene expression programs. Phase III of the ENCODE Project profiled 66 mouse epigenomes across twelve tissues at daily intervals from embryonic day 11.5 to birth. Applying the ChromHMM algorithm to these epigenomes, we annotated eighteen chromatin states with characteristics of promoters, enhancers, transcribed regions, repressed regions, and quiescent regions. Our integrative analyses delineate the tissue specificity and developmental trajectory of the loci in these chromatin states. Approximately 0.3% of each epigenome is assigned to a bivalent chromatin state, which harbors both active marks and the repressive mark H3K27me3. Highly evolutionarily conserved, these loci are enriched in silencers bound by polycomb repressive complex proteins, and the transcription start sites of their silenced target genes. This collection of chromatin state assignments provides a useful resource for studying mammalian development.



Genetics ◽  
2021 ◽  
Author(s):  
Xiaofen Wu ◽  
Kongyan Niu ◽  
Xiaofan Wang ◽  
Jing Zhao ◽  
Han Wang ◽  
...  

Abstract Inflammaging refers to low-grade, chronically activated innate immunity that has deleterious effects on healthy lifespan. However, little is known about the intrinsic signaling pathway that elicits innate immune genes during aging. Here using Drosophila melanogaster, we profile the microRNA targetomes in young and aged animals, and reveal Dawdle (Daw), an activin-like ligand of the TGF-β pathway, as a physiological target of microRNA-252 (miR-252). We show that miR-252 cooperates with Forkhead box O (FoxO), a conserved transcriptional factor implicated in aging, to repress Daw. Unopposed Daw triggers hyper activation of innate immune genes coupled with a decline in organismal survival. Using adult muscle tissues, single-cell sequencing analysis describes that Daw and its downstream innate immune genes are expressed in distinct cell types, suggesting a cell non-autonomous mode of regulation. We further determine the genetic cascade by which Daw signaling leads to increased Kenny/IKKγ protein, which in turn activates Relish/NF-κB protein and consequentially innate immune genes. Finally, transgenic increase of miR-252 and FoxO pathway factors in wild-type Drosophila extends lifespan and mitigates the induction of innate immune genes in aging. Together, we propose that miR-252 and FoxO promote healthy longevity by cooperative inhibition on Daw mediated inflammaging.



2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Marin Jane McBride ◽  
Kristina Durham ◽  
Bernardo L Trigatti

Interleukin-15 (IL-15) is a pleotropic cytokine that has a profound effect on the proliferation, survival and differentiation of many distinct cell types. The IL-15 receptor complex has 3 subunits: the unique receptor chain IL-15 receptor alpha (IL-15Rα), and two receptor chains shared with interleukin-2 (IL-2) and/or other cytokines, referred to as IL-2 receptor beta (IL-2Rβ) and IL-2 receptor gamma/gamma common chain (IL-2Rγ/γc), respectively. To our knowledge, this is the first study to examine the effects of IL-15 in immortalized human cardiomyocytes. Data collected by RT-PCR shows mRNA expression of IL-15Rα, IL-2Rβ and IL-2 Rγ/γc in these cells. Additionally, western blotting for IL-15Rα, IL-2Rβ and IL-2 Rγ/γc confirms the presence of all three IL-15 receptors. Early experiments examining the effect of IL-15 on cardiomyocyte cell survival show a statistically significant protective effect of IL-15 on the survival of cells exposed to tunicamycin, a pharamacological endoplasmic reticulum (ER) stress inducing agent. These findings suggest that IL-15 signaling may be an important cardioprotective pathway that is involved in the cardiac ER stress response. As ER stress is a major component of multiple different cardiac pathologies, such as myocardial infarction, heart failure and diabetes, uncovering the molecular mechanism by which IL-15 protects the heart will allow for deeper understanding of the cardiac ER stress response.



2018 ◽  
Vol 116 (1) ◽  
pp. 303-312 ◽  
Author(s):  
Erol C. Bayraktar ◽  
Lou Baudrier ◽  
Ceren Özerdem ◽  
Caroline A. Lewis ◽  
Sze Ham Chan ◽  
...  

Mitochondria are metabolic organelles that are essential for mammalian life, but the dynamics of mitochondrial metabolism within mammalian tissues in vivo remains incompletely understood. While whole-tissue metabolite profiling has been useful for studying metabolism in vivo, such an approach lacks resolution at the cellular and subcellular level. In vivo methods for interrogating organellar metabolites in specific cell types within mammalian tissues have been limited. To address this, we built on prior work in which we exploited a mitochondrially localized 3XHA epitope tag (MITO-Tag) for the fast isolation of mitochondria from cultured cells to generate MITO-Tag Mice. Affording spatiotemporal control over MITO-Tag expression, these transgenic animals enable the rapid, cell-type-specific immunoisolation of mitochondria from tissues, which we verified using a combination of proteomic and metabolomic approaches. Using MITO-Tag Mice and targeted and untargeted metabolite profiling, we identified changes during fasted and refed conditions in a diverse array of mitochondrial metabolites in hepatocytes and found metabolites that behaved differently at the mitochondrial versus whole-tissue level. MITO-Tag Mice should have utility for studying mitochondrial physiology, and our strategy should be generally applicable for studying other mammalian organelles in specific cell types in vivo.



2018 ◽  
Author(s):  
Erol Can Bayraktar ◽  
Lou Baudrier ◽  
Ceren Özerdem ◽  
Caroline A. Lewis ◽  
Sze Ham Chan ◽  
...  

ABSTRACTMitochondria are metabolic organelles that are essential for mammalian life, but the dynamics of mitochondrial metabolism within mammalian tissues in vivo remains incompletely understood. While whole-tissue metabolite profiling has been useful for studying metabolism in vivo, such an approach lacks resolution at the cellular and subcellular level. In vivo methods for interrogating organellar metabolites in specific cell-types within mammalian tissues have been limited. To address this, we built on prior work in which we exploited a mitochondrially-localized 3XHA epitope-tag (“MITO-Tag”) for the fast isolation of mitochondria from cultured cells to now generate “MITO-Tag Mice.” Affording spatiotemporal control over MITO-Tag expression, these transgenic animals enable the rapid, cell-type-specific immunoisolation of mitochondria from tissues, which we verified using a combination of proteomic and metabolomic approaches. Using MITO-Tag Mice and targeted and untargeted metabolite profiling, we identified changes during fasted and refed conditions in a diverse array of mitochondrial metabolites in hepatocytes and found metabolites that behaved differently at the mitochondrial versus whole-tissue level. MITO-Tag Mice should have utility for studying mitochondrial physiology and our strategy should be generally applicable for studying other mammalian organelles in specific cell-types in vivo.



Sign in / Sign up

Export Citation Format

Share Document