Intercellular Distance Research Articles

Expression of lncRNA AK058003 in esophageal carcinoma and analysis of its intervention effect.

The aim of this study was to investigate the expression of long non-coding ribonucleic acid (lncRNA) AK058003 in esophageal carcinoma (EC) tissues, and to analyze its intervention effect. The expression of lncRNA AK058003 in EC tissues and para-carcinoma tissues from 130 EC patients was detected via quantitative Polymerase Chain Reaction (qPCR). EC cell lines were selected for exogenous interference in lncRNA AK058003. Subsequently, the expression of lncRNA AK058003 in normal esophageal epithelial cell line (Het-1A) and EC cell lines (EC109, EC9706, KYSE-150, KYSE-30, and TE-1) was detected by qPCR. EC9706 cell lines with the highest expression of lncRNA AK058003 were selected and transfected with lncRNA AK058003 siRNA and lncRNA AK058003 control, respectively. After transfection, the expression of lncRNA AK058003 was determined using PCR. The changes in cell growth and proliferation were analyzed via cell growth curve and cell cycle assay. Meanwhile, the changes in cell migration and invasion were analyzed through wound healing assay. Protein expressions of matrix metalloproteinase-1 (MMP1) and MMP2 were determined by Western blot. Clinical data were collected from EC patients, and the association between lncRNA AK058003 expression and tumor-node-metastasis (TNM) stage was finally analyzed. LncRNA AK058003 was highly expressed EC tissues compared with para-carcinoma tissues (p<0.01). Compared with Het-1A cells, the expression of lncRNA AK058003 was significantly higher in EC109, EC9706, KYSE-150, KYSE-30, and TE-1 cells, with highest level in EC9706 cells (p<0.05). The expression of lncRNA AK058003 remarkably declined in lncRNA AK058003 siRNA group compared with lncRNA AK058003 control group (p<0.001). Compared with lncRNA AK058003 control group, the proliferation of EC cells was significantly weakened in lncRNA AK058003 siRNA group, with the greatest difference at 3 d. Flow cytometry results revealed that cell cycle was arrested in G0/G1 phase in lncRNA AK058003 siRNA group. Wound healing assay indicated that the intercellular distance became large, and cell migration ability was evidently enhanced in lncRNA AK058003 siRNA group with time (p<0.05). Besides, the protein expressions of MMP1 and MMP2 were remarkably lower in lncRNA AK058003 siRNA group than those in lncRNA AK058003 control group. This indicated remarkably declined invasion and metastasis ability. In addition, the postoperative prognosis was significantly worse in patients with higher expression of lncRNA AK058003 (p<0.05). All these findings suggested that lncRNA AK058003 could serve as a biomarker for EC prognosis. LncRNA AK058003 is highly expressed in EC patients, which promotes proliferation, migration, invasion, and metastasis of EC cells. In addition, the postoperative prognosis of EC patients with high expression of lncRNA AK058003 is relatively poor.

Lead acetate- induced neurodegenerative changes in the dorsolateral prefrontal cortex of mice: the role of Vitexin.

This study was aimed at investigating the neuroprotective effect of Vitexin against lead (Pb) induced neurodegenerative changes in the dorsolateral prefrontal cortex (DLPFC) and working memory in mice. Thirty-two adolescent male albino mice were divided into four groups (n=8). Control group received 0.2 mL of normal saline; Pb group received 100 mg/kg of Pb acetate for 14 days, Vitexin group received 1mg/kg of Vitexin for 14 days, and Pb+Vitexin group received 100 mg/kg of Pb acetate and 1 mgkg of Vitexin for 14 days. Barnes maze test and novel object recognition test were done to ascertain working memory. Histoarchitectural assessment of DLPFC was done with haematoxylin and eosin (H&E), cresyl fast violet and congo red stains. Furthermore, cell count and other morphometric measurements were done. There was significant decline in working memory in the Pb group, but a combination of Pb+Vitexin improved the working memory. Vitexin significantly reduced neuronal death and chromatolysis caused by Pb. Amyloid aggregation was not observed in any of the groups. This study has shown that concurrent administration of Vitexin and Pb will significantly reduce neurodegeneration and improve working memory. However, Pb treatment or Pb+Vitexin treatment does not have any effect on intercellular distance, neuronal length and the cross-sectional area of neurons in layer III of DLPFC.

An Electro-Mechanical Pro-Tray Seeder for Sowing Vegetable Seeds

Developing technology to pick and place singulated vegetable seeds into pro-trays is a felt need amidst the nursery growing entrepreneurs. A simple electro-mechanical machine was developed which does not require sophisticated controls and a separate source of vacuum. The unit can fill in the growth media in the pro-trays, level it off, compact the media in the cells, pick and place singulated vegetable seeds in the compacted cells and finally re-top the pro-tray for watering and germination. The whole process is done on a flat belt conveyor moving in steps of inter-cellular distance of the pro-tray, thus doing the sequence of operations in each row of the pro-tray. The machine on being tested provided about 60 per cent of singulation in flat seeds, but 100 per cent in round seeds. Flat seeds, if pelleted, provided 100 per cent singulation. The machine has a through-put of 80 trays per hour of operation

Quantification of the morphological characteristics of hESC colonies

The maintenance of the undifferentiated state in human embryonic stem cells (hESCs) is critical for further application in regenerative medicine, drug testing and studies of fundamental biology. Currently, the selection of the best quality cells and colonies for propagation is typically performed by eye, in terms of the displayed morphological features, such as prominent/abundant nucleoli and a colony with a tightly packed appearance and a well-defined edge. Using image analysis and computational tools, we precisely quantify these properties using phase-contrast images of hESC colonies of different sizes (0.1–1.1 {{bf{text{mm}}}}^{{bf{2}}}) during days 2, 3 and 4 after plating. Our analyses reveal noticeable differences in their structure influenced directly by the colony area {boldsymbol{A}}. Large colonies (A > 0.6 mm2) have cells with smaller nuclei and a short intercellular distance when compared with small colonies (A < 0.2 mm2). The gaps between the cells, which are present in small and medium sized colonies with A ≤ 0.6 mm2, disappear in large colonies (A > 0.6 mm2) due to the proliferation of the cells in the bulk. This increases the colony density and the number of nearest neighbours. We also detect the self-organisation of cells in the colonies where newly divided (smallest) cells cluster together in patches, separated from larger cells at the final stages of the cell cycle. This might influence directly cell-to-cell interactions and the community effects within the colonies since the segregation induced by size differences allows the interchange of neighbours as the cells proliferate and the colony grows. Our findings are relevant to efforts to determine the quality of hESC colonies and establish colony characteristics database.

Induction of Apoptosis and Growth-Inhibition by Thymoquinone in ACHN and GP-293 Cell Lines in Comparable with Cis-Platinum

ObjectiveIn the current work, we investigated the cytotoxic and apoptotic effects of Thymoquinone (TQ), an active compound of Nigella sativa (N. sativa) and Cis-platinum, on normal renal epithelial (GP-293) and human renal adenocarcinoma cell lines (ACHN).MethodsGP-293 and ACHN cell lines were cultured in Dulbecco’s modified Eagle’s medium (DMEM) with 10% Fetal bovine serum (FBS) and 1% penicillin plus streptomycin antibiotic. The MTT assay was used for cellular viability assessment. Viability of cells was observed using inverted light microscope 24, 48 and 72 h after exposure of the cells to various concentrations of TQ (1, 2.5, 5, 10, 50 and 100 μg/ml) and Cis-platinum (0.5, 1, 1.5, 2, 3, 6 and 12.5 μg/ml). Moreover, apoptosis was analyzed with a flow-cytometry method. The untreated cells were considered as control group.ResultsMorphological changes such as reduced cell number and increased intercellular distance and reduced cell viability in ACHN and GP-293cell lines were observed in both TQ and Cis-platinum groups; however, Cis-platinum had greater effect on ACHN cell line than GP-293 cell line. In addition, GP-293 cell line was more sensitive to TQ compared to ACHN cell line. Furthermore, TQ and Cis-platinum had apoptotic effects on both ACHN and GP-293 cell lines.ConclusionOur findings demonstrated that TQ and Cis-platinum had cytotoxic and apoptotic effects on both cell lines, However, GP-293 cell line was more sensitive to TQ. Additionally, Cis-platinum was more effective on ACHN cell line than on GP-293 cell line.

Ultrastructure of intestinal mucosa in diarrhea-predominant irritable bowel syndrome.

Impaired intestinal barrier function has been demonstrated in the pathophysiology of diarrhea-predominant irritable bowel syndrome (IBS-D). This study aimed to describe the intestinal ultrastructural findings in the intestinal mucosal layer of IBS-D patients. In total, 10 healthy controls and 10 IBS-D patients were analyzed in this study. The mucosa of each patient's rectosigmoid colon was first assessed by confocal laser endomicroscopy (CLE); next, biopsied specimens of these sites were obtained. Intestinal tissues of IBS-D patients and healthy volunteers were examined to observe cellular changes by transmission electron microscopy (TEM). CLE showed no visible epithelial damage or inflammatory changes in the colonic mucosa of IBS-D compared with healthy volunteers. On transmission electron microscopic examination, patients with IBS-D displayed a larger apical intercellular distance with a higher proportion of dilated (>20nm) intercellular junctional complexes, which was indicative of impaired mucosal integrity. In addition, microvillus exfoliation, extracellular vesicle as well as increased presence of multivesicular bodies were visible in IBS-D patients. Single epithelial cells appeared necrotic, as characterized by cytoplasmic vacuolization, cytoplasmic swelling, and presence of autolysosome. A significant association between bowel habit, frequency of abdominal pain, and enlarged intercellular distance was found. This study showed ultrastructural alterations in the architecture of intestinal epithelial cells and intercellular junctional complexes in IBS-D patients, potentially representing a pathophysiological mechanism in IBS-D.

A multiphysics analysis of the strain energy in multicellular environments

This letter considers the strain energy distribution in cell assemblies. Our scalable model consists of N-core-shell spherical structures modeling biological cells with assumptions based on two fundamental premises. First, we use a finite element in the framework of time-domain to solve for the electrodeformation and cell electroporation when a well-defined electrical stimulus is delivered to a multicellular environment. Second, the strain-stress response of the cell assemblies is characterized by a relaxation time which is much larger than the time constant of the membrane charging. A “switch off” (corresponding to times after electrical pulsing) phenomenon observed in the strain energy signal might provide an interesting discriminant test capable of providing different information on the proximity (coupling) effect between cell and assembly anisotropy depending on the type of electrical stimulus employed. In the explicit examples we study, we learn up to date facts about how the local enhancement of the electric field, deformation of the cell, strain energy, and relative area occupied by the pores are modified by varying the intercellular distance distribution.

Properties of cardiac conduction in a cell-based computational model.

The conduction of electrical signals through cardiac tissue is essential for maintaining the function of the heart, and conduction abnormalities are known to potentially lead to life-threatening arrhythmias. The properties of cardiac conduction have therefore been the topic of intense study for decades, but a number of questions related to the mechanisms of conduction still remain unresolved. In this paper, we demonstrate how the so-called EMI model may be used to study some of these open questions. In the EMI model, the extracellular space, the cell membrane, the intracellular space and the cell connections are all represented as separate parts of the computational domain, and the model therefore allows for study of local properties that are hard to represent in the classical homogenized bidomain or monodomain models commonly used to study cardiac conduction. We conclude that a non-uniform sodium channel distribution increases the conduction velocity and decreases the time delays over gap junctions of reduced coupling in the EMI model simulations. We also present a theoretical optimal cell length with respect to conduction velocity and consider the possibility of ephaptic coupling (i.e. cell-to-cell coupling through the extracellular potential) acting as an alternative or supporting mechanism to gap junction coupling. We conclude that for a non-uniform distribution of sodium channels and a sufficiently small intercellular distance, ephaptic coupling can influence the dynamics of the sodium channels and potentially provide cell-to-cell coupling when the gap junction connection is absent.

Morpho-palynological assessment of medicinal flora of district Lahore, Pakistan based on LM and SEM.

This study was carried out to identify 20 high valued medicinal plants of District Lahore, Punjab, Pakistan with the help of the palynological studies. The distinguishing characteristics for selected species were found by systematized methods using light microscopy and Scanning Electron Microscopy. In this study, important pollen qualitative and quantitative features of these medicinal species such as polar and equatorial outline and their diameter, P/E ratio, presence or absence of pore, sculpturing of pollen, exine thickness, intine thickness, intercellular distance of exine and intine, presence or absence of spines, length of spines, width of spines, presence or absence of colpi and length of colpi, were compared. Remarkable variations in these pollen characters have been observed. Pollen grains were usually circular-semicircular (Calendula officinalis), spheroidal (Convolvulus arvensis), bilobed and trilobed (Convolvulus arvensis), spiny, (Abutilon indicum), oblate (Terminalia chebula) and elongated (Euphorbia pilulifera). In polar view Conyza bonariensis exhibited the highest pollen size [195.9 (211.6-180.2) μm]. While in equatorial view Calendula officinalis and Euphorbia pilulifera had lowest value [22.5 (20-25) μm] whereas Carissa carandas [165 (140-179) μm] appeared to be the largest. Parthenium hysterophorus showed the highest P/E ratio, that is, 1.28. Colpi were reported in only 7 species. Most of the plants showed 100% fertility but Terminalia chebula showed the least value 35%. In the present, project the diversity in pollen morphology present pollen as a valuable taxonomic tool. It is also concluded that pollen features are helpful at the specific level as well as generic level and can provide us fruitful taxonomic solutions. RESEARCH HIGHLIGHTS: Palynological flora of the medicinal plant species of district Lahore, Pakistan is investigated first time on the basis of LM and SEM and the flora is found very significant for taxonomic investigations.

Interaction of the Bored Sand and Gravel Drain Pile with the Surrounding Compacted Loam Soil and Foundation Raft Taking into Account Rheological Properties of the Loam Soil and Non-Linear Properties of the Drain Pile

The task of the interaction of the sand and gravel drain pile with the surrounding loam soil after its preliminary deep compaction and formation of the composite ground cylinder from the drain pile and surrounding compacted loam soil (cells) is considered in the article. It is seen that the subsidence and carrying capacity of such cell considerably depends on physical and mechanical properties of the compacted drain piles and surrounding loam soil as well as their diameter and intercellular distance. The strain-stress state of the cell is considered not taking into account its component elements, but taking into account linear and elastic-plastic properties of the drain pile and creep flow of the surrounding loam soil. It is stated that depending on these properties the distribution and redistribution of the load on a cell takes place from the foundation raft between the drain pile and surrounding soil. Based on the results of task solving the formulas and charts are given demonstrating the ratio of the load between the drain pile and surrounding loam soil in time.

Structure and dynamics of multicellular assemblies measured by coherent light scattering

Determining the structure and the internal dynamics of tissues is essential to understand their functional organization. Microscopy allows for monitoring positions and trajectories of every single cell. Those data are useful to extract statistical observables, such as intercellular distance, tissue symmetry and anisotropy, and cell motility. However, this procedure requires a large and supervised computational effort. In addition, due to the large cross-section of cells, the light scattering limits the use of microscopy to relatively thin samples. As an alternative approach, we propose to take advantage of light scattering and to analyze the dynamical diffraction pattern produced by a living tissue illuminated with coherent light. In this article, we illustrate with a few examples that supra-cellular structures produce an exploitable diffraction signal. From the diffraction signal, we deduce the mean distance between cells, the anisotropy of the supra-cellular organization and, from its fluctuations, the mean speed of moving cells. This easy to implement technique considerably reduces analysis time, allowing real time monitoring.

Knockdown of sodium–calcium exchanger 1 induces epithelial-to-mesenchymal transition in kidney epithelial cells

Mesenchymal-to-epithelial transition (MET) and epithelial-to-mesenchymal transition (EMT) are important processes in kidney development. Failure to undergo MET during development leads to the initiation of Wilms tumor, whereas EMT contributes to the development of renal cell carcinomas (RCC). The role of calcium regulators in governing these processes is becoming evident. We demonstrated earlier that Na+/Ca2+ exchanger 1 (NCX1), a major calcium exporter in renal epithelial cells, regulates epithelial cell motility. Here, we show for the first time that NCX1 mRNA and protein expression was down-regulated in Wilms tumor and RCC. Knockdown of NCX1 in Madin-Darby canine kidney cells induced fibroblastic morphology, increased intercellular junctional distance, and induced paracellular permeability, loss of apico-basal polarity in 3D cultures, and anchorage-independent growth, accompanied by expression of mesenchymal markers. We also provide evidence that NCX1 interacts with and anchors E-cadherin to the cell surface independent of NCX1 ion transport activity. Consistent with destabilization of E-cadherin, NCX1 knockdown cells showed an increase in β-catenin nuclear localization, enhanced transcriptional activity, and up-regulation of downstream targets of the β-catenin signaling pathway. Taken together, knockdown of NCX1 in Madin-Darby canine kidney cells alters epithelial morphology and characteristics by destabilization of E-cadherin and induction of β-catenin signaling.

Abstract 3931: Sodium-calcium exchanger-1 regulates the epithelial phenotype and is lost in renal cancers

Abstract Epithelial cells that line the renal tubules possess apico-basal polarity and a defined cellular structure maintained by junctional proteins. The underlying mesenchymal cells are fibroblastic with a non-uniform cell structure and secrete extracellular matrix proteins. Mesenchymal to epithelial transition (MET) and epithelial to mesenchymal transition (EMT) are required for renal tubule formation during kidney development. Failure of renal mesenchymal cells to undergo epithelial transformation leads to the initiation of Wilms tumor, the most frequently occurring renal cancer in children. Conversely, aberrant mesenchymal transformation of tubular epithelial cells in the nephron contributes to the development of renal cell carcinoma, which constitutes 85-90% of the adult tubular malignancies. The role of calcium regulators in governing EMT and MET is becoming evident. Sodium calcium exchanger 1 (NCX1), located on the basolateral surface of tubular epithelial cells, is the principal calcium regulator that mediates calcium reabsorption in these cells. NCX1 mediates the extrusion of one calcium ion and the influx of three sodium ions in one exchange movement. We demonstrated earlier that NCX1 regulates epithelial cell motility. However, the role of NCX1 in EMT was undetermined. We observed that knockdown of NCX1 in renal epithelial cells (MDCK) induced fibroblastic morphology, and increased permeability to rhodamine indicative of leaky cell-cell junctions. Electron micrographs of these cells displayed increased inter-cellular junctional distance also suggesting that NCX1 knockdown altered junctions between adjacent cells. Cells with NCX1 knockdown showed loss of apico-basal polarity in three-dimensional cultures accompanied by expression of mesenchymal markers. Furthermore, NCX1 knockdown cells were capable of anchorage independent growth suggesting that these cells had acquired tumorigenic potential. Interestingly, we show for the first time that NCX1 mRNA and protein expression is greatly reduced in both Wilms tumor and renal cell carcinoma demonstrating a direct correlation between NCX1 expression and the epithelial phenotype. Mechanistically, we provide evidence that NCX1 interacts with and anchors E-cadherin, a classical adhesion molecule, to the cell surface independent of NCX1 ion transport activity. MDCK cells with NCX1 knockdown exhibited β-catenin nuclear localization and enhanced transcriptional activity. Taken together, knockdown of NCX1 in MDCK cells induces mesenchymal transition by destabilization of E-cadherin and induction of β-catenin transcriptional activity. Citation Format: Sona Lakshme Balasubramaniam, Anilkumar Gopalakrishnapillai, Nicholas J. Petrelli, Sonali P. Barwe. Sodium-calcium exchanger-1 regulates the epithelial phenotype and is lost in renal cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3931. doi:10.1158/1538-7445.AM2017-3931

Concentration of Glial Cell Line-Derived Neurotrophic Factor Positively Correlates with Symptoms in Functional Dyspepsia.

In patients with functional dyspepsia (FD), mild duodenal inflammation correlates with increased mucosal permeability. Enteric glial cells can produce glial cell line-derived neurotrophic factor (GDNF) to repair disrupted epithelial barrier function. We examined the role of duodenal GDNF in FD pathophysiology and its association with dyspeptic symptoms. Duodenal biopsies taken from FD patients and control subjects were used for analysis. GDNF protein expression and localization were examined. Cellular infiltration of eosinophils and mast cells was measured. We also examined the intercellular space between the adjacent epithelial cells at the apical junction complex using transmission electron microscopy. In FD patients, expression of GDNF protein was significantly increased compared with controls, 107.3 (95.3-136.7) versus 49.3 (38.0-72.6) pg/mg protein (median (interquartile range), p=0.006), respectively. GDNF was localized in enteric glial cells, eosinophils, and epithelial cells. The number of eosinophils was significantly greater in FD patients than in controls, 1039 (923-1181) versus 553 (479-598) cells/mm2 (p=0.021), respectively. The intercellular space was dilated at the adherent junction in FD patients compared to control patients, 32.4 (29.8-34.8) versus 22.0 (19.9-26.1) nm (p=0.002), respectively. Intercellular distance positively correlated with the frequency of postprandial fullness and early satiation (p=0.001, r=0.837 and p=0.009, r=0.693, respectively). Expression of GDNF correlated with epigastric burning (p=0.041, r=0.552). Increased expression of duodenal GDNF might be involved in FD pathophysiology and symptom perception.

Microfabrication of a tunable collagen/alginate-chitosan hydrogel membrane for controlling cell–cell interactions

Indirect cell contact co-culture system is increasingly becoming more attractable owing to their advantages of easy cell separation and desirable outcomes for cell–cell interactions. However, how to precisely control the spatial position of cells within multicellular co-cultures is still experimentally challenging due to the incapability of the conventional methods in vitro. In the present study, a tunable collagen/alginate-chitosan (Col/Alg-Chi) membrane was established, which was capable of controlling intercellular distance between the neighboring cells at a level of micrometer resolution. It was showed that intercellular distance between the hepatocytes and the fibroblasts exerted significant influence on hepatic function in vitro. In particular, maintenance of the functionality of primary hepatocytes requires direct contact between the hepatocytes and their supportive stromal cells, and their effective contact distance is within 30μm. This technical platform would potentially enable investigations of dynamic cell–cell interaction in a multitude of applications including organogenesis, development or even neoplastic transformation.

Substrate Regulation of Cytoskeletal Order and Beating Strain Dynamics of Cardiomyocytes

Recent experiments [1] show that both striation, an indication of the structural registry in muscle fibers, as well as the contractile strains produced by beating cardiac muscle cells, can be optimized by substrate stiffness. We show theoretically how the substrate rigidity dependence of the registry data can be mapped onto that of the strain measurements. We determine [2] the elasticity-mediated structural registry including both the elastic interactions of neighboring, actively contractile acto-myosin units as well as the noise inherent in biological systems. By assuming that structurally registered myofibrils also tend to beat in phase, we explain the observed dependence of both structural striation and beating strain measurements of heart muscle cells on substrate stiffness in a unified manner. The agreement of our ideas with experiment suggests that the correlated beating of heart cells may be limited by the structural registry of the myofibrils which in turn is regulated by their elastic environment. New theoretical predictions focus on the role of the substrate and the intercellular distance in the synchronization of the beating of cellular assemblies. [1] S. Majkut et al., Current Biology, 23, 2323 (2013). [2] K. Dasbiswas, S. Majkut, D. Discher and S. Safran, Nature Comm., 6, 7085 (2015). Experimental Collaborations - Dennis Discher, Stephanie Majkut (Penn); Shelly Tzlil (Technion).

Fabrication of a tunable hydrogel membrane for constructing indirect cell coculture system

ABSTRACTIn this study, an improved indirect cell coculture system was constructed by using a polyelectrolyte complex membrane generated by alginate (A) and chitosan (C). Methodologies of characterizing thickness and permeability of flat AC membrane were first established due to the importance of these two parameters in determining intercellular distance and degree of contact between cocultured cells. Compared to reaction time, both alginate concentration and molecular weight (Mw) of chitosan play more dominant roles in determining the membrane thickness and diffusion coefficients. Moreover, cells in the alginate gel and on the AC membrane could maintain high cell viability. Thus, an improved indirect cell coculture system constructed by flat AC membrane was fabricated and characterized, which provides a robust tool to study the effect of intercellular distance and degree of contact between cocultured cells on cell–cell interactions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43100.

Expression of interleukin‐12 by adipose‐derived mesenchymal stem cells for treatment of lung adenocarcinoma

BackgroundStudies have revealed mesenchymal cells tend to directionally migrate toward tumor cells and inhibit tumor growth. However, there have been rare reports about adipose-derived mesenchymal stem cells (AMSCs), which achieved stable expression of interleukin (IL)-12 to inhibit lung adenocarcinoma cell migration and invasion. We aimed to achieve stable expression of IL-12 in AMSCs through transgenic technology and utilize the paracrine effect of IL-12 to inhibit lung adenocarcinoma cell migration and invasion.MethodsAdipose-derived AMSCs were transduced with lentivirus encoding IL-12. IL-12/AMSCs and lung adenocarcinoma A549 cells were co-cultured using a cylinder column to assess cellular attraction, and expression of Ki67 was detected. Dual-chamber transwell experiments were used to assess migration and invasiveness of A549 cells exposed to conditioned media from IL-12/AMSCs.ResultsWhen A549 cells were co-cultured with lentivirus vectors (LV)-IL-12-green fluorescent protein (GFP)/AMSCs, the intercellular distance was great (346.44 ± 41.07 μm vs. 201.58 ± 27.96 μm vs. 191.45 ± 24.07 μm) (F = 25.414, P < 0.05); the Ki67-positive rate was low (59.13 ± 17.21% vs. 92.31 ± 6.11% vs. 94.25 ± 5.27%) (F = 21.426, P < 0.05). When the lower Transwell chamber contained culture medium from LV-IL-12-GFP/AMSCs, the percentage of the invasive A549 cells was low (31.55 ± 6.21% vs. 70.65 ± 10.46% vs. 68.65 ± 9.50%) (F = 27.494, P < 0.05). The percentages of colonized A549 cells that invaded the culture media of LV-IL-12-GFP/AMSCs were low (4.46 ± 1.21 vs. 10.11 ± 2.07 vs. 9.48 ± 1.4) (F = 23.219, P < 0.05).ConclusionsAMSCs could target lung carcinoma and mediate stable expression of IL-12, to play a role in tumor treatment.

Controlling cell–cell interactions using surface acoustic waves

The interactions between pairs of cells and within multicellular assemblies are critical to many biological processes such as intercellular communication, tissue and organ formation, immunological reactions, and cancer metastasis. The ability to precisely control the position of cells relative to one another and within larger cellular assemblies will enable the investigation and characterization of phenomena not currently accessible by conventional in vitro methods. We present a versatile surface acoustic wave technique that is capable of controlling the intercellular distance and spatial arrangement of cells with micrometer level resolution. This technique is, to our knowledge, among the first of its kind to marry high precision and high throughput into a single extremely versatile and wholly biocompatible technology. We demonstrated the capabilities of the system to precisely control intercellular distance, assemble cells with defined geometries, maintain cellular assemblies in suspension, and translate these suspended assemblies to adherent states, all in a contactless, biocompatible manner. As an example of the power of this system, this technology was used to quantitatively investigate the gap junctional intercellular communication in several homotypic and heterotypic populations by visualizing the transfer of fluorescent dye between cells.

Dissipative particle dynamics simulations of deformation and aggregation of healthy and diseased red blood cells in a tube flow

In this paper, we report simulation results assessing the deformation and aggregation of mixed healthy and malaria-infected red blood cells (RBCs) in a tube flow. A three dimensional particle model based on Dissipative Particle Dynamics (DPD) is developed to predict the tube flow containing interacting cells. The cells are also modelled by DPD, with a Morse potential to characterize the cell-cell interaction. As validation tests, a single RBC in a tube flow and two RBCs in a static flow are simulated to examine the cell deformation and intercellular interaction, respectively. The study of two cells, one healthy and the other malaria-infected RBCs in a tube flow demonstrates that the malaria-infected RBC (in the leading position along flow direction) has different effects on the healthy RBC (in the trailing position) at the different stage of parasite development or at the different capillary number. With parasitic development, the malaria-infected RBC gradually loses its deformability, and in turn the corresponding trailing healthy RBC also deforms less due to the intercellular interaction. With increasing capillary number, both the healthy and malaria-infected RBCs are likely to undergo an axisymmetric motion. The minimum intercellular distance becomes small enough so that rouleaux is easily formed, i.e., the healthy and malaria-infected RBCs are difficultly disaggregated.