scholarly journals INTERCELLULAR COMMUNICATION AND TISSUE GROWTH

1967 ◽  
Vol 33 (2) ◽  
pp. 235-242 ◽  
Author(s):  
Werner R. Loewenstein ◽  
Richard D. Penn

Intercellular communication was examined in regenerating rat liver and urodele skin, two tissues of fast but normal growth. In both, cellular communication is in general as good as in their respective normal intact state. This stands in striking contrast to the lack of cellular communication in tissues with cancerous growth. Upon wounding of the urodele skin, the normally permeable junctional membranes of cells near the wound border seal themselves off, thereby insulating the interiors of the communicated cell systems from the exterior. When the cells of two opposing borders make mechanical contact in the course of wound closure, communication between them ensues within 30 min. Within this period all cell movement also ceases ("contact inhibition"). The possible implications of these findings in the control of tissue growth are discussed.

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1445
Author(s):  
Taisa Nogueira Pansani ◽  
Thanh Huyen Phan ◽  
Qingyu Lei ◽  
Alexey Kondyurin ◽  
Bill Kalionis ◽  
...  

Extracellular vesicles (EVs) are nanoparticles released by cells that contain a multitude of biomolecules, which act synergistically to signal multiple cell types. EVs are ideal candidates for promoting tissue growth and regeneration. The tissue regenerative potential of EVs raises the tantalizing possibility that immobilizing EVs on implant surfaces could potentially generate highly bioactive and cell-instructive surfaces that would enhance implant integration into the body. Such surfaces could address a critical limitation of current implants, which do not promote bone tissue formation or bond bone. Here, we developed bioactive titanium surface coatings (SurfEV) using two types of EVs: secreted by decidual mesenchymal stem cells (DEVs) and isolated from fermented papaya fluid (PEVs). For each EV type, we determined the size, morphology, and molecular composition. High concentrations of DEVs enhanced cell proliferation, wound closure, and migration distance of osteoblasts. In contrast, the cell proliferation and wound closure decreased with increasing concentration of PEVs. DEVs enhanced Ca/P deposition on the titanium surface, which suggests improvement in bone bonding ability of the implant (i.e., osteointegration). EVs also increased production of Ca and P by osteoblasts and promoted the deposition of mineral phase, which suggests EVs play key roles in cell mineralization. We also found that DEVs stimulated the secretion of secondary EVs observed by the presence of protruding structures on the cell membrane. We concluded that, by functionalizing implant surfaces with specialized EVs, we will be able to enhance implant osteointegration by improving hydroxyapatite formation directly at the surface and potentially circumvent aseptic loosening of implants.


2021 ◽  
Author(s):  
George Courcoubetis ◽  
Chi Xu ◽  
Sergey Nuzhdin ◽  
Stephan Haas

AbstractIn the physicists’ perspective, epithelial tissues constitute an exotic type of active matter with non-linear properties reminiscent of amorphous materials. In the context of a circular proliferating epithelium, modeled by the quasistatic vertex model, we identify novel discrete tissue scale rearrangements, i.e. cellular flow avalanches, which are a form of collective cell movement. During the avalanches, the cellular trajectories are radial in the periphery and form a vortex in the core. After the onset of these avalanches, the epithelial area grows discontinuously. The avalanches are found to be stochastic, and their strength is determined by the density of cells in the tissue. Overall, avalanches regularize the spatial tension distribution along tissue. Furthermore, the avalanche distribution is found to obey a power law, with an exponent consistent with sheer induced avalanches in amorphous materials. To decipher the role of avalanches in organ development, we simulate epithelial growth of theDrosophilaeye disc during the third instar using a computational model, which includes both signaling and mechanistic signalling. During the third instar, the morphogenetic furrow (MF), a ∼10 cell wide wave of apical area constriction propagates through the epithelium, making it a system with interesting mechanical properties. These simulations are used to understand the details of the growth process, the effect of the MF on the growth dynamics on the tissue scale, and to make predictions. The avalanches are found to depend on the strength of the apical constriction of cells in the MF, with stronger apical constriction leading to less frequent and more pronounced avalanches. The results herein highlight the dependence of simulated tissue growth dynamics on relaxation timescales, and serve as a guide forin vitroexperiments.


Development ◽  
1967 ◽  
Vol 17 (3) ◽  
pp. 607-616
Author(s):  
Richard D. Campbell

Morphogenesis has been extensively studied in many hydroids, both during normal growth (Kühn, 1914; Berrill, 1961) and during regeneration (Tardent, 1963). Less is known about the patterns of cell proliferation underlying changes in tissue form. In several cases where cell division has been studied, surprisingly little direct correlation was found between areas of apparent morphological growth and patterns of cell proliferation (Overton, 1963; Crowell, Wyttenbach & Suddith, 1965; Shostak, Patel & Burnett, 1965; Wyttenbach, 1965; Campbell, 1967a, b). To explore further the relations between tissue growth and body form, I have examined histologically hydroids of two genera, Tubularia and Hydractinia, each of which has morphological pecularities. Tubularia possesses two whorls of tentacles and one whorl of gonophores, and thus has as many distinct hydranth regions as any hydroid. In the Hydractinia colony, four morphologically distinct polyp types are present.


Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1595 ◽  
Author(s):  
Sungjoo Park ◽  
Eunsu Ko ◽  
Jun Hyoung Lee ◽  
Yoseb Song ◽  
Chang-Hao Cui ◽  
...  

Cutaneous wound healing is a well-orchestrated event in which many types of cells and growth factors are involved in restoring the barrier function of skin. In order to identify whether ginsenosides, the main active components of Panax ginseng, promote wound healing, the proliferation and migration activities of 15 different ginsenosides were tested by MTT assay and scratched wound closure assay. Among ginsenosides, gypenoside LXXV (G75) showed the most potent wound healing effects. Thus, this study aimed to investigate the effects of G75 on wound healing in vivo and characterize associated molecular changes. G75 significantly increased proliferation and migration of keratinocytes and fibroblasts, and promoted wound closure in an excision wound mouse model compared with madecassoside (MA), which has been used to treat wounds. Additionally, RNA sequencing data revealed G75-mediated significant upregulation of connective tissue growth factor (CTGF), which is known to be produced via the glucocorticoid receptor (GR) pathway. Consistently, the increase in production of CTGF was confirmed by western blot and ELISA. In addition, GR-competitive binding assay and GR translocation assay results demonstrated that G75 can be bound to GR and translocated into the nucleus. These results demonstrated that G75 is a newly identified effective component in wound healing.


Author(s):  
Yuka Okusha ◽  
Takanori Eguchi ◽  
Manh Tien Tran ◽  
Chiharu Sogawa ◽  
Kaya Yoshida ◽  
...  

Matrix metalloproteinase 3 (MMP3) plays multiple roles in pro-tumorigenic proteolysis and in intracellular transcription. These include inducing connective tissue growth factor [CTGF, also known as cellular communication network factor 2 (CCN2)] and prompting a new definition of MMP3 as a moonlighting metalloproteinase. Members of the MMP family have been found within tumor-derived extracellular vesicles (EVs) such as oncosomes or exosomes. We here investigated the roles of MMP3-rich oncosomes in tumor progression, molecular transmission, and gene regulation. MMP3 and CCN2/CTGF were significantly co-expressed in tumor samples derived from patients suffering from colorectal adenocarcinoma. We found that oncosomes derived from a rapidly metastatic colon cancer cells (LuM1) were enriched in MMP3 and a C-terminal half fragment of CCN2/CTGF. MMP3-rich oncosomes were highly transmissive into recipient cells and were pro-tumorigenic in an allograft mouse model. Oncosome-derived MMP3 was transmissive into recipient cell nuclei, trans-activated CCN2/CTGF promoter, and induced CCN2/CTGF production at 1 to 6 hours after the addition of oncosomes to culture media. In addition, CRISPR/Cas9-mediated knockout of MMP3 showed significant anti-tumor effects, including inhibition of migration and invasion of LuM1 cells in vitro, inhibition of tumor growth in vivo, and reduction of CCN2/CTGF and its promoter activity in vitro. These data newly demonstrate that the oncosome-derived moonlighting metalloproteinase promotes metastasis and is pro-tumorigenic at distant sites as well as a transmissive trans-activator for the cellular communication network gene.


1968 ◽  
Vol 38 (3) ◽  
pp. 556-561 ◽  
Author(s):  
A. Jamakosmanović ◽  
W. R. Loewenstein

Intercellular communication was examined in normal and cancerous isolated thyroids with an intracellular electrical technique. The cells of normal thyroid (rat, mouse, hamster, man) communicate, within any given follicle, through permeable junctions. The cells of a wide variety of thyroid cancers (rat, hamster) do not communicate to any detectable degree and have resting membrane potentials lower than those of normal cells.


1969 ◽  
Vol 1 (1) ◽  
pp. 274-293 ◽  
Author(s):  
Carmia Borek ◽  
S. Higashino ◽  
W. R. Loewenstein

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