scholarly journals ExoBow: A transgenic strategy to study CD63 exosomes in vivo

2021 ◽  
Author(s):  
Bárbara Adem ◽  
Nuno Bastos ◽  
Carolina F. Ruivo ◽  
Patrícia F. Vieira ◽  
Barbara Seidler ◽  
...  

ABSTRACTExosomes are described as central players in a myriad of biological processes. However, the available methodologies to study their function in complex biological systems in vivo are still very limited. The biodistribution of endogenously produced exosomes, the ability to trace their spontaneous flow in order to identify the cell types they interact with, remains a major challenge. New tools to identify comprehensive networks of communication established by exosomes originated in distinct cell types in vivo, are fundamental for a better understanding of their biology. Here, we describe the development of a genetically engineered mouse model that allows the expression of the mouse CD63 exosomal marker fused with one (monocolor) or up to four fluorescent proteins (multireporter), the ExoBow. The genetic design of the ExoBow transgene allows the conditional expression of the reporters in any tissue/cell-type in an inducible or non-inducible fashion. In addition, communication mediated by CD63 positive (CD63+) exosomes can be identified amongst the same tissue/cell types using the multireporter version of the model, in order to map intra-organ/tissue communication. We demonstrate the applicability of the ExoBow transgene in normal physiological conditions and in the context of cancer, using pancreas as a working model. The ExoBow comprises a unique strategy to identify intra- and inter-organ/cell-type communication mediated by CD63+ exosomes. We believe this tool will contribute for a better understanding of the complex interactions occurring in vivo that underly the biology of exosomes in health and disease.

2019 ◽  
Author(s):  
Laura E. Sanman ◽  
Ina W. Chen ◽  
Jake M. Bieber ◽  
Veronica Steri ◽  
Byron Hann ◽  
...  

AbstractRenewing tissues have the remarkable ability to continually produce both proliferative progenitor and specialized differentiated cell-types. How are complex milieus of microenvironmental signals interpreted to coordinate tissue cell-type composition? Here, we develop a high-throughput approach that combines organoid technology and quantitative imaging to address this question in the context of the intestinal epithelium. Using this approach, we comprehensively survey enteroid responses to individual and paired perturbations to eight epithelial signaling pathways. We uncover culture conditions that enrich for specific cell-types, including Lgr5+ stem and enteroendocrine cells. We analyze interactions between perturbations and dissect mechanisms underlying an unexpected mutual antagonism between EGFR and IL-4 signals. Finally, we show that, across diverse perturbations, modulating proliferation of transit-amplifying cells also consistently changes the composition of differentiated secretory and absorptive cell-types. This property is conserved in vivo and can arise from differential amplification of secretory and absorptive progenitor cells. Taken together, the observations highlight an underappreciated role for transit-amplifying cells in which proliferation of these short-lived progenitors provides a lineage-based mechanism for tuning differentiated cell-type composition.


Microbiology ◽  
2009 ◽  
Vol 155 (6) ◽  
pp. 1786-1799 ◽  
Author(s):  
Catriona Donovan ◽  
Marc Bramkamp

The process of endospore formation in Bacillus subtilis is complex, requiring the generation of two distinct cell types, a forespore and larger mother cell. The development of these cell types is controlled and regulated by cell type-specific gene expression, activated by a σ-factor cascade. Activation of these cell type-specific sigma factors is coupled with the completion of polar septation. Here, we describe a novel protein, YuaG, a eukaryotic reggie/flotillin homologue that is involved in the early stages of sporulation of the Gram-positive model organism B. subtilis. YuaG localizes in discrete foci in the membrane and is highly dynamic. Purification of detergent-resistant membranes revealed that YuaG is associated with negatively charged phospholipids, e.g. phosphatidylglycerol (PG) or cardiolipin (CL). However, localization of YuaG is not always dependent on PG/CL in vivo. A yuaG disruption strain shows a delay in the onset of sporulation along with reduced sporulation efficiency, where the spores develop to a certain stage and then appear to be trapped at this stage. Our results indicate that YuaG is involved in the early stage of spore development, probably playing a role in the signalling cascade at the onset of sporulation.


2021 ◽  
Author(s):  
Asif Zubair ◽  
Richard H. Chapple ◽  
Sivaraman Natarajan ◽  
William C. Wright ◽  
Min Pan ◽  
...  

The disorganization of cell types within tissues underlies many human diseases and has been studied for over a century using the conventional tools of pathology, including tissue-marking dyes such as the H&E stain. Recently, spatial transcriptomics technologies were developed that can measure spatially resolved gene expression directly in pathology-stained tissues sections, revealing cell types and their dysfunction in unprecedented detail. In parallel, artificial intelligence (AI) has approached pathologist-level performance in computationally annotating H&E images of tissue sections. However, spatial transcriptomics technologies are limited in their ability to separate transcriptionally similar cell types and AI-based pathology has performed less impressively outside their training datasets. Here, we describe a methodology that can computationally integrate AI-annotated pathology images with spatial transcriptomics data to markedly improve inferences of tissue cell type composition made over either class of data alone. We show that this methodology can identify regions of clinically relevant tumor immune cell infiltration, which is predictive of response to immunotherapy and was missed by an initial pathologist's manual annotation. Thus, combining spatial transcriptomics and AI-based image annotation has the potential to exceed pathologist-level performance in clinical diagnostic applications and to improve the many applications of spatial transcriptomics that rely on accurate cell type annotations.


2020 ◽  
Author(s):  
Emily A. McGlade ◽  
Gerardo G. Herrera ◽  
Kalli K. Stephens ◽  
Sierra L. W. Olsen ◽  
Sarayut Winuthayanon ◽  
...  

AbstractOne of the endogenous estrogens, 17β-estradiol (E2) is a female steroid hormone secreted from the ovary. It is well established that E2 causes biochemical and histological changes in the uterus. The oviduct response to E2 is virtually unknown in an in vivo environment. In this study, we assessed the effect of E2 on each oviductal cell type, using an ovariectomized-hormone-replacement mouse model, single cell RNA-sequencing (scRNA-seq), in situ hybridization, and cell-type-specific deletion in mice. We found that each cell type in the oviduct responded to E2 distinctively, especially ciliated and secretory epithelial cells. The treatment of exogenous E2 did not drastically alter the transcriptomic profile from that of endogenous E2 produced during estrus. Moreover, we have identified and validated genes of interest in our datasets that may be used as cell- and region-specific markers in the oviduct. Insulin-like growth factor 1 (Igf1) was characterized as an E2-target gene in the mouse oviduct and was also expressed in human Fallopian tubes. Deletion of Igf1 in progesterone receptor (Pgr)-expressing cells resulted in female subfertility, partially due to an embryo developmental defect and embryo retention within the oviduct. In summary, we have shown that oviductal cell types are differentially regulated by E2 and support gene expression changes that are required for normal embryo development and transport in mouse models.


2018 ◽  
Author(s):  
Caroline Fecher ◽  
Laura Trovò ◽  
Stephan A. Müller ◽  
Nicolas Snaidero ◽  
Jennifer Wettmarshausen ◽  
...  

AbstractMitochondria vary in morphology and function in different tissues, however little is known about their molecular diversity among cell types. To investigate mitochondrial diversity in vivo, we developed an efficient protocol to isolate cell type-specific mitochondria based on a new MitoTag mouse. We profiled the mitochondrial proteome of three major neural cell types in cerebellum and identified a substantial number of differential mitochondrial markers for these cell types in mice and humans. Based on predictions from these proteomes, we demonstrate that astrocytic mitochondria metabolize long-chain fatty acids more efficiently than neurons. Moreover, we identified Rmdn3 as a major determinant of ER-mitochondria proximity in Purkinje cells. Our novel approach enables exploring mitochondrial diversity on the functional and molecular level in many in vivo contexts.


Author(s):  
Shivangi Agarwal ◽  
Yashwanth R Sudhini ◽  
Onur K Polat ◽  
Jochen Reiser ◽  
Mehmet Mete Altintas

Kidneys, one of the vital organs in our body, are responsible for maintaining whole-body homeostasis. The complexity of renal function (e.g., filtration, reabsorption, fluid and electrolyte regulation, urine production) demands diversity not only at the level of cell types but also in their overall distribution and structural framework within the kidney. To gain an in-depth molecular-level understanding of the renal system, it is imperative to discern the components of kidney and the types of cells residing in each of the sub-regions. Recent developments in labeling, tracing, and imaging techniques enabled us to mark, monitor and identify these cells in vivo with high efficiency in a minimally invasive manner. In this review, we have summarized different cell types, specific markers that are uniquely associated with those cell types, and their distribution in kidney, which altogether make kidneys so special and different. Cellular sorting based on the presence of certain proteins on the cell surface allowed for assignment of multiple markers for each cell type. However, different studies using different techniques have found contradictions in the cell-type specific markers. Thus, the term "cell marker" might be imprecise and sub-optimal, leading to uncertainty when interpreting the data. Therefore, we strongly believe that there is an unmet need to define the best cell markers for a cell type. Although, the compendium of renal-selective marker proteins presented in this review is a resource that may be useful to the researchers, we acknowledge that the list may not be necessarily exhaustive.


2018 ◽  
Vol 98 (1) ◽  
pp. 391-418 ◽  
Author(s):  
Deniz Atasoy ◽  
Scott M. Sternson

Chemogenetic technologies enable selective pharmacological control of specific cell populations. An increasing number of approaches have been developed that modulate different signaling pathways. Selective pharmacological control over G protein-coupled receptor signaling, ion channel conductances, protein association, protein stability, and small molecule targeting allows modulation of cellular processes in distinct cell types. Here, we review these chemogenetic technologies and instances of their applications in complex tissues in vivo and ex vivo.


2018 ◽  
Vol 115 (20) ◽  
pp. 5253-5258 ◽  
Author(s):  
Hideyuki Yanai ◽  
Shiho Chiba ◽  
Sho Hangai ◽  
Kohei Kometani ◽  
Asuka Inoue ◽  
...  

IFN regulatory factor 3 (IRF3) is a transcription regulator of cellular responses in many cell types that is known to be essential for innate immunity. To confirm IRF3’s broad role in immunity and to more fully discern its role in various cellular subsets, we engineered Irf3-floxed mice to allow for the cell type-specific ablation of Irf3. Analysis of these mice confirmed the general requirement of IRF3 for the evocation of type I IFN responses in vitro and in vivo. Furthermore, immune cell ontogeny and frequencies of immune cell types were unaffected when Irf3 was selectively inactivated in either T cells or B cells in the mice. Interestingly, in a model of lipopolysaccharide-induced septic shock, selective Irf3 deficiency in myeloid cells led to reduced levels of type I IFN in the sera and increased survival of these mice, indicating the myeloid-specific, pathogenic role of the Toll-like receptor 4–IRF3 type I IFN axis in this model of sepsis. Thus, Irf3-floxed mice can serve as useful tool for further exploring the cell type-specific functions of this transcription factor.


2021 ◽  
Vol 27 ◽  
Author(s):  
Aline Araujo Zuma ◽  
Wanderley de Souza

: Chagas disease is a Neglected Tropical Disease (NTD), and although endemic in Latin America, affects around 6-7 million people infected worldwide. The treatment of Chagas disease is based on benznidazole and nifurtimox, which are the only available drugs. However, they are not effective during the chronic phase and cause several side effects. Furthermore, BZ promotes cure in 80% of the patients in the acute phase, but the cure rate drops to 20% in adults in the chronic phase of the disease. In this review, we present several studies published in the last six years, which describes the antiparasitic potential of distinct drugs, from the synthesis of new compounds aiming to target the parasite, as well as the repositioning and the combination of drugs. We highlight several compounds for having shown results that are equivalent or superior to BZ, which means that they should be further studied, either in vitro or in vivo. Furthermore, we stand out the differences in the effects of BZ on the same strain of T. cruzi, which might be related to methodological differences such as parasite and cell ratios, host cell type and the time of adding the drug. In addition, we discuss the wide variety of strains and also the cell types used as a host cell, which makes it difficult to compare the trypanocidal effect of the compounds.


2019 ◽  
Vol 7 (1) ◽  
pp. 6 ◽  
Author(s):  
Charlotte Kelley ◽  
Erin Cram

The reproductive system of the hermaphroditic nematode C. elegans consists of a series of contractile cell types—including the gonadal sheath cells, the spermathecal cells and the spermatheca–uterine valve—that contract in a coordinated manner to regulate oocyte entry and exit of the fertilized embryo into the uterus. Contraction is driven by acto-myosin contraction and relies on the development and maintenance of specialized acto-myosin networks in each cell type. Study of this system has revealed insights into the regulation of acto-myosin network assembly and contractility in vivo.


Sign in / Sign up

Export Citation Format

Share Document