scholarly journals Cell-cell signaling elicits local Ca2+ transients in melanocyte dendrites and dendritic spine-like structures

2018 ◽  
Author(s):  
Rachel L. Belote ◽  
Sanford M. Simon
Keyword(s):  
Dendritic Spines ◽  
Cell Communication ◽  
Human Keratinocytes ◽  
Cell Types ◽  
Primary Human Keratinocytes ◽  
Human Melanocytes ◽  
Neuronal Functions ◽  
Dendritic Branches ◽  
Cell Cell

AbstractCompartmentalized cytoplasmic fluctuations of Ca2+ within dendrites and dendritic spines regulate a variety of neuronal functions. Like some neurons and glia, melanocytes are neural crest derived and possess dendrites (Adameyko et al., 2009; Erickson et al., 1992; Fitzpatrick and Szabo, 1959). Here, we show that primary human melanocytes, when observed in situ have extensive dendritic branches with dendritic spines similar to neurons. When co-cultured with primary human keratinocytes, they have local Ca2+ transients within these spines and within the dendrites. These are elicited by secreted factors from adjacent keratinocytes. Thus other cell types with dendrites are capable of compartmentalized Ca2+ fluctuations in response to cell-cell communication. Furthermore, our observations within intact human skin suggest a more complex communication network between adjacent melanocytes and keratinocytes, and thus a more complex physiology to skin than previous appreciated.

scholarly journals Distinct purinergic signaling pathways in prepubescent mouse spermatogonia

2016 ◽  
Vol 148 (3) ◽  
pp. 253-271 ◽  
Author(s):  
David Fleck ◽  
Nadine Mundt ◽  
Felicitas Bruentgens ◽  
Petra Geilenkirchen ◽  
Patricia A. Machado ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Purinergic Signaling ◽  
Cell Communication ◽  
Atp Release ◽  
Cell Types ◽  
Control Male ◽  
Electrophysiological Recordings ◽  
Unique Approach

Spermatogenesis ranks among the most complex, yet least understood, developmental processes. The physiological principles that control male germ cell development in mammals are notoriously difficult to unravel, given the intricate anatomy and complex endo- and paracrinology of the testis. Accordingly, we lack a conceptual understanding of the basic signaling mechanisms within the testis, which control the seminiferous epithelial cycle and thus govern spermatogenesis. Here, we address paracrine signal transduction in undifferentiated male germ cells from an electrophysiological perspective. We identify distinct purinergic signaling pathways in prepubescent mouse spermatogonia, both in vitro and in situ. ATP—a dynamic, widespread, and evolutionary conserved mediator of cell to cell communication in various developmental contexts—activates at least two different spermatogonial purinoceptor isoforms. Both receptors operate within nonoverlapping stimulus concentration ranges, display distinct response kinetics and, in the juvenile seminiferous cord, are uniquely expressed in spermatogonia. We further find that spermatogonia express Ca2+-activated large-conductance K+ channels that appear to function as a safeguard against prolonged ATP-dependent depolarization. Quantitative purine measurements additionally suggest testicular ATP-induced ATP release, a mechanism that could increase the paracrine radius of initially localized signaling events. Moreover, we establish a novel seminiferous tubule slice preparation that allows targeted electrophysiological recordings from identified testicular cell types in an intact epithelial environment. This unique approach not only confirms our in vitro findings, but also supports the notion of purinergic signaling during the early stages of spermatogenesis.

scholarly journals IL-6 loss causes ventricular dysfunction, fibrosis, reduced capillary density, and dramatically alters the cell populations of the developing and adult heart

2009 ◽  
Vol 296 (5) ◽  
pp. H1694-H1704 ◽  
Author(s):  
Indroneal Banerjee ◽  
John W. Fuseler ◽  
Arti R. Intwala ◽  
Troy A. Baudino
Keyword(s):  
Cardiac Function ◽  
Cardiac Fibroblasts ◽  
Cell Communication ◽  
Cell Types ◽  
Capillary Density ◽  
Cell Populations ◽  
Cardiac Cell ◽  
Altered Expression ◽  
Cell Cell

Interleukin-6 (IL-6) is a pleiotropic cytokine responsible for many different processes including the regulation of cell growth, apoptosis, differentiation, and survival in various cell types and organs, including the heart. Recent studies have indicated that IL-6 is a critical component in the cell-cell communication between myocytes and cardiac fibroblasts. In this study, we examined the effects of IL-6 deficiency on the cardiac cell populations, cardiac function, and interactions between the cells of the heart, specifically cardiac fibroblasts and myocytes. To examine the effects of IL-6 loss on cardiac function, we used the IL-6 −/− mouse. IL-6 deficiency caused severe cardiac dilatation, increased accumulation of interstitial collagen, and altered expression of the adhesion protein periostin. In addition, flow cytometric analyses demonstrated dramatic alterations in the cardiac cell populations of IL-6 −/− mice compared with wild-type littermates. We observed a marked increase in the cardiac fibroblast population in IL-6 −/− mice, whereas a concomitant decrease was observed in the other cardiac cell populations examined. Moreover, we observed increased cell proliferation and apoptosis in the developing IL-6 −/− heart. Additionally, we observed a significant decrease in the capillary density of IL-6 −/− hearts. To elucidate the role of IL-6 in the interactions between cardiac fibroblasts and myocytes, we performed in vitro studies and demonstrated that IL-6 deficiency attenuated the activation of the STAT3 pathway and VEGF production. Taken together, these data demonstrate that a loss of IL-6 causes cardiac dysfunction by shifting the cardiac cell populations, altering the extracellular matrix, and disrupting critical cell-cell interactions.

Amino- and Carboxy-functionalized Nano- and Microstructured Surfaces for Evaluating the Impact of Non-biological Stimuli on Adhesion, Proliferation and Differentiation of Primary Skin-Cells

2009 ◽  
Vol 1187 ◽  
Author(s):  
Petra J. Kluger ◽  
Marc Panas ◽  
Lena Schober ◽  
Guenter E. M. Tovar ◽  
Heike Mertsching ◽  
...  
Keyword(s):  
Focal Adhesions ◽  
Human Keratinocytes ◽  
Cell Types ◽  
Primary Human Keratinocytes ◽  
Chemical Functionalization ◽  
Skin Cells ◽  
Functionalized Surfaces ◽  
Microstructured Surfaces ◽  
Primary Skin Cells ◽  
The Impact

AbstractTo gain basic insight into the impact of non-biological features on cells’ behaviour, primary skin-cells, keratinocytes and fibroblasts, were cultured on amine-functionalized or carboxy-functionalized planar, nano- or microstructured surfaces. Sintered layers of silica nano- or microparticles were used to fabricate structures in the range of naturally occurring structure-sizes. Organo-chemical functionalization was achieved using organo-functional silanes. Primary human keratinocytes and fibroblasts were isolated from human foreskin and cultivated on the modified interfaces. Both cell-types displayed specific proliferation behaviour, depending on surface topography and chemical functionalization: Keratinocytes showed significantly better proliferation on amino-functionalized surfaces than on carboxy-functionalized surfaces. On amino-functional surfaces decree-topography. Fibroblasts, in contrast, tended to proliferate stronger on carboxylated surfaces. Immunohistological staining proofed that actin and vinculin, which is involved in the formation of focal adhesions, were expressed on all modified surfaces, thus revealing intact cytoskeleton and cell-substrate contacts.

scholarly journals Kalinin is more efficient than laminin in promoting adhesion of primary keratinocytes and some other epithelial cells and has a different requirement for integrin receptors.

1994 ◽  
Vol 125 (1) ◽  
pp. 205-214 ◽  
Author(s):  
P Rousselle ◽  
M Aumailley
Keyword(s):  
Cell Adhesion ◽  
Epithelial Cells ◽  
Culture Media ◽  
Human Keratinocytes ◽  
Cell Types ◽  
Heat Denaturation ◽  
Integrin Subunit ◽  
Cellular Interactions ◽  
Primary Human Keratinocytes ◽  
Established Cell

Kalinin was purified from squamous cell carcinoma (SCC25) spent culture media using an immunoaffinity column prepared from the mAb BM165. The affinity-purified material was separated by SDS-PAGE into three bands of 165-155, 140, and 105 kD identical to those obtained from normal human keratinocyte cultures and previously identified as kalinin. Kalinin promoted adhesion of a large number of normal cells and established cell lines with an activity similar to other adhesion molecules such as the laminin-nidogen complex, fibronectin, or collagen IV. However, kalinin was a much better substrate than laminin-nidogen complex for adhesion of cells of epithelial origin including primary human keratinocytes. Adhesion to kalinin was followed by cell shape changes ranging from rounded to fully spread cells depending on the cell types. The adhesion-promoting activity of kalinin was conformation dependent and was abolished by heat denaturation. mAb BM165 prevented cell adhesion to kalinin but not to other extracellular matrix substrates. However, either complete or partial inhibition was observed with different cells suggesting the existence of at least two cell-binding sites on the kalinin molecule. Experiments inhibiting cell adhesion with function-blocking anti-integrin subunit antibodies indicated that both alpha 3 beta 1 and alpha 6 beta 1 integrins are involved in the cellular interactions with kalinin, while for cell adhesion to classical mouse Engelbreth-Holm-Swarm laminin only alpha 6 beta 1 integrins, and not alpha 3 beta 1, appeared to be functional. Altogether, these results suggest that kalinin may fulfill additional functions than laminin, particularly for epithelial cells.

scholarly journals Alternative Fates of Keratinocytes Transduced by Human Papillomavirus Type 18 E7 during Squamous Differentiation

2002 ◽  
Vol 76 (6) ◽  
pp. 2964-2972 ◽  
Author(s):  
Wei-Ming Chien ◽  
Francisco Noya ◽  
Heather M. Benedict-Hamilton ◽  
Thomas R. Broker ◽  
Louise T. Chow
Keyword(s):  
Human Papillomavirus ◽  
Cyclin E ◽  
Dna Amplification ◽  
Human Keratinocytes ◽  
S Phase ◽  
Primary Human Keratinocytes ◽  
P27kip1 Protein ◽  
Differentiated Cells ◽  
Hpv 18

ABSTRACT The human papillomavirus type 18 (HPV-18) E7 protein promotes S-phase reentry in postmitotic, differentiated keratinocytes in squamous epithelium to facilitate vegetative viral DNA amplification. To examine the nature and fate of the differentiated cells that reenter S phase, organotypic cultures of primary human keratinocytes transduced with HPV-18 E7 were pulse-chase-pulse-labeled with 3H-thymidine (3H-TdR) and bromodeoxyuridine (BrdU). The kinetics of the appearance of doubly labeled suprabasal cells demonstrate that E7 expression did not promote prolonged S phase. Rather, there was a considerable lag before a small percentage of the cells reentered another round of S phase. Fluorescence in situ hybridization analysis, indeed, revealed a small fraction of the cells with more than 4n chromosomes in the differentiated strata. Differentiated cells positive for 3H-TdR, BrdU, or both often had enlarged nuclei or were binucleated. These results suggest that S phase is not followed by cell division, although nuclear division may occur. Interestingly, a significant fraction of differentiated cells that entered S phase subsequently accumulated p27kip1 protein with a kinetics preceding the accumulation of cyclin E. We conclude that E7-transduced, differentiated keratinocytes that enter S phase have two alternative fates: (i) a low percentage of cells undergoes endoreduplication, achieving higher than 4n ploidy, and (ii) a high percentage of cells accumulates the p27kip1, cyclin E, and p21cip1 proteins, resulting in arrest and preventing further S-phase reentry.

scholarly journals FlyPhoneDB: An integrated web-based resource for cell-cell communication prediction in Drosophila

2021 ◽  
Author(s):  
Yifang Liu ◽  
Yanhui Hu ◽  
Joshua Shing Shun Li ◽  
Jonathan Rodiger ◽  
Aram Comjean ◽  
...  
Keyword(s):  
Cell Communication ◽  
Cell Types ◽  
Data Sets ◽  
High Confidence ◽  
Web Based ◽  
Communication Events ◽  
Single Cell Rna Sequencing ◽  
Biological Interpretation ◽  
Multicellular Organisms ◽  
Cell Cell

Multicellular organisms rely on cell-cell communication to exchange information necessary for developmental processes and metabolic homeostasis. Cell-cell communication pathways can be inferred from transcriptomic datasets based on ligand-receptor (L-R) expression. Recently, data generated from single cell RNA sequencing (scRNA-seq) have enabled L-R interaction predictions at an unprecedented resolution. While computational methods are available to infer cell-cell communication in vertebrates such a tool does not yet exist for Drosophila. Here, we generated a high confidence list of L-R pairs for the major fly signaling pathways and developed FlyPhoneDB, a quantification algorithm that calculates interaction scores to predict L-R interactions between cells. At the FlyPhoneDB user interface, results are presented in a variety of tabular and graphical formats to facilitate biological interpretation. To demonstrate that FlyPhoneDB can effectively identify active ligands and receptors to uncover cell-cell communication events, we applied FlyPhoneDB to Drosophila scRNA-seq data sets from adult midgut, abdomen, and blood, and demonstrate that FlyPhoneDB can readily identify previously characterized cell-cell communication pathways. Altogether, FlyPhoneDB is an easy-to-use framework that can be used to predict cell-cell communication between cell types from scRNA-seq data in Drosophila.

scholarly journals Microfluidic system-based time-course tracking of physical proximity between cells and its effect on gene expression for elucidating live single cancer-immune cell interactions

2021 ◽  
Author(s):  
Bianca C.T Flores ◽  
Smriti Chawla ◽  
Ning Ma ◽  
Chad Sanada ◽  
Praveen Kumar Kujur ◽  
...  
Keyword(s):  
Gene Expression ◽  
Time Course ◽  
Immune Cell ◽  
Cell Communication ◽  
Time Lapse ◽  
Cell Types ◽  
Temporal Variations ◽  
Microfluidic System ◽  
Cell Interactions ◽  
Cell Cell

Cell-cell communication and physical interactions play a vital role in cancer initiation, homeostasis, progression, and immune response. Here, we report a system that combines live capture of different cell types, co-incubation, time-lapse imaging, and gene expression profiling of doublets using a microfluidic integrated fluidic circuit (IFC) that enables measurement of physical distances between cells and the associated transcriptional profiles due to cell-cell interactions. The temporal variations in natural killer (NK) - triple-negative breast cancer (TNBC) cell distances were tracked and compared with terminally profiled cellular transcriptomes. The results showed the time-bound activities of regulatory modules and alluded to the existence of transcriptional memory. Our experimental and bioinformatic approaches serve as a proof of concept for interrogating live cell interactions at doublet resolution, which can be applied across different cancers and cell types.

scholarly journals Ultraviolet radiation stimulates a biphasic pattern of 1,2-diacylglycerol formation in cultured human melanocytes and keratinocytes by activation of phospholipases C and D

1995 ◽  
Vol 305 (2) ◽  
pp. 471-477 ◽  
Author(s):  
C J Carsberg ◽  
J Ohanian ◽  
P S Friedmann
Keyword(s):  
Ultraviolet Radiation ◽  
Human Keratinocytes ◽  
Cell Types ◽  
Pigment Cells ◽  
Melanin Synthesis ◽  
3T3 Fibroblasts ◽  
Transient Rise ◽  
Human Melanocytes ◽  
Early Rise ◽  
B16 Mouse Melanoma

Ultraviolet radiation (UVR) induces melanin synthesis by human epidermal melanocytes, and phospholipid-derived 1,2-diacylglycerols (DAGs) have been implicated in mediating this response. In previous experiments, addition of the synthetic DAG 1-oleoyl-2-acetylglycerol to cultured pigment cells stimulated melanogenesis. The purpose of the present study was to analyse the effects of UVR on the endogenous generation of DAGs. It was found that in a number of cultured cell types, including human melanocytes and B16 mouse melanoma cells, but also human keratinocytes and Swiss 3T3 fibroblasts, exposure to a single dose of UVR stimulated a biphasic increase in endogenous DAG formation. An early transient rise, over seconds, was followed by a more sustained delayed rise over minutes. The early rise in DAG levels was accompanied by a transient rise in inositol trisphosphate formation, indicating activation of phosphatidylinositol-specific phospholipase C. The delayed rise was accompanied by activation of phospholipase D. This endogenous DAG formation by pigment cells is further evidence for the involvement of DAGs in UVR-induced epidermal melanin synthesis. Since DAG formation is also seen in other cells types, it is possible that DAGs may be involved in an array of UVR-induced responses.

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