PubMed Health⌕ Search

PubMed · 15818740

Differential gene expression during capillary morphogenesis in a microcarrier-based three-dimensional in vitro model of angiogenesis with focus on chemokines and chemokine receptors.

Abstract

AIM: To globally compare the gene expression profiles during the capillary morphogenesis of human microvascular endothelial cells (HMVECs) in an in vitro angiogenesis system with affymetrix oligonucleotide array. METHODS: A microcarrier-based in vitro angiogenesis system was developed, in which ECs migrated into the matrix, proliferated, and formed capillary sprouts. The sprouts elongated, branched and formed networks. The total RNA samples from the HMVECs at the selected time points (0.5, 24, and 72 h) during the capillary morphogenesis were used for microarray analyses, and the data were processed with the softwares provided by the manufacturers. The expression patterns of some genes were validated and confirmed by semi-quantitative RT-PCR. The regulated genes were grouped based on their molecular functions and expression patterns, and among them the expression of chemokines and chemokine receptors was specially examined and their functional implications were analyzed. RESULTS: A total of 1 961 genes were up- or down-regulated two-folds or above, and among them, 468 genes were up- or down-regulated three-folds or above. The regulated genes could be grouped into categories based on their molecular functions, and were also clustered into six groups based on their patterns of expression. As for chemokines and chemokine receptors, CXCL1/GRO-alpha, CXCL2/GRO-beta, CXCL5/ENA-78, CXCL6/GCP2, IL-8/CXCL8, CXCL12/SDF-1, CXCL9/Mig, CXC11/ITAC, CX3CL1/fractalkine, CCL2/MCP-1, CCL3, CCL5/RANTES, CCL7, CCL15, CCL21, CCL23, CCL28, and CCR1, CCR9, CXCR4 were identified. Moreover, these genes demonstrated different changing patterns during the capillary morphogenesis, which implied that they might have different roles in the sequential process. Among the chemokines identified, CCL2/MCP-1, CCL5/RANTES and CX3CL1 were specially up-regulated at the 24-h time point when the sprouting characterized the morphological change. It was thus suggested that they might exert crucial roles at the early stage of angiogenesis. CONCLUSION: The present study demonstrates a global profile of gene expression during endothelial capillary morphogenesis, and the results provide us much information about the molecular mechanisms of angiogenesis, with which further evaluation of individual genes can be conducted.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Xi-Tai Sun, Min-Yue Zhang, Chang Shu, Qiang Li, Xiao-Gui Yan, Ni Cheng, Yu-Dong Qiu, Yi-Tao Ding. 2005-04-21. Differential gene expression during capillary morphogenesis in a microcarrier-based three-dimensional in vitro model of angiogenesis with focus on chemokines and chemokine receptors.. https://doi.org/10.3748/wjg.v11.i15.2283

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Cell patterning using magnetite nanoparticles and magnetic force.

Technologies for fabricating functional tissue architectures by patterning cells precisely are highly desirable for tissue engineering. Although several cell patterning methods such as microcontact printing and lithography have been developed, these methods require specialized surfaces to be used as substrates, the fabrication of which is time consuming. In the present study, we demonstrated a simple and rapid cell patterning technique, using magnetite nanoparticles and magnetic force, which enables us to allocate cells on arbitrary surfaces. Magnetite cationic liposomes (MCLs) developed in our previous study were used to magnetically label the target cells. When steel plates placed on a magnet were positioned under a cell culture surface, the magnetically labeled cells lined on the surface where the steel plate was positioned. Patterned lines of single cells were achieved by adjusting the number of cells seeded, and complex cell patterns (curved, parallel, or crossing patterns) were successfully fabricated. Since cell patterning using magnetic force may not limit the property of culture surfaces, human umbilical vein endothelial cells (HUVECs) were patterned on Matrigel, thereby forming patterned capillaries. These results suggest that the novel cell patterning methodology, which uses MCLs, is a promising approach for tissue engineering and studying cell-cell interactions in vitro.

Cell Culture Techniques↗

Investigation of metabolic objectives in cultured hepatocytes.

Using optimization based methods to predict fluxes in metabolic flux balance models has been a successful approach for some microorganisms, enabling construction of in silico models and even inference of some regulatory motifs. However, this success has not been translated to mammalian cells. The lack of knowledge about metabolic objectives in mammalian cells is a major obstacle that prevents utilization of various metabolic engineering tools and methods for tissue engineering and biomedical purposes. In this work, we investigate and identify possible metabolic objectives for hepatocytes cultured in vitro. To achieve this goal, we present a special data-mining procedure for identifying metabolic objective functions in mammalian cells. This multi-level optimization based algorithm enables identifying the major fluxes in the metabolic objective from MFA data in the absence of information about critical active constraints of the system. Further, once the objective is determined, active flux constraints can also be identified and analyzed. This information can be potentially used in a predictive manner to improve cell culture results or clinical metabolic outcomes. As a result of the application of this method, it was found that in vitro cultured hepatocytes maximize oxygen uptake, coupling of urea and TCA cycles, and synthesis of serine and urea. Selection of these fluxes as the metabolic objective enables accurate prediction of the flux distribution in the system given a limited amount of flux data; thus presenting a workable in silico model for cultured hepatocytes. It is observed that an overall homeostasis picture is also emergent in the findings.

Cell Culture Techniques↗

Quantitation of interaction of lipids with polymer surfaces in cell culture.

As cell culture medium development efforts have progressed towards leaner, serum-free, and chemically defined formulations, it has become increasingly important to ensure that the appropriate concentrations of all nutrients are maintained and delivered at point of use. In light of concurrent efforts to progress to disposable polymeric storage and culture platforms, the characterization and control of medium component interactions with container surfaces can be a key issue in ensuring consistent delivery of these medium formulations. These studies characterize the interactions of lipids with culture surfaces typically encountered in the bioprocess industry using model systems. The extent and kinetics of lipid association with polymeric surfaces were determined using radio-labeled linoleic acid and cholesterol. The effect of methyl-beta-cyclodextrin, a component commonly used to solubilize lipids in culture media, on association kinetics was also examined. In addition, loss of lipids across a sterilizing membrane filter was quantified. We find that there is potential for significant loss of hydrophobic components due to non-specific binding to surfaces at timescales relevant to a typical cell culture process. The extent of loss is dependent on the nature of the hydrophobic component as well as the type of surface. These studies highlight the potential of the extracellular environment to modify medium composition and also emphasize the importance of medium formulation strategies, including those used in the delivery of hydrophobic components. It is noted, however, that the level of loss is very dependent on the specific system including the composition of the culture medium used.

Cell Culture Techniques↗