Project description:Subcutaneous implantation of cellulose sponges has been used for decades to induce vital granulation tissue formation. Illumina microarray was done in order to study the early gene expression in the granulation tissue formation.
Project description:Subcutaneous implantation of cellulose sponges has been used for decades to induce vital granulation tissue formation. Illumina microarray was done in order to study the early gene expression in the granulation tissue formation. A total of six samples from six different rats was analyzed. Three samples were collected after 24 hours of implantation and three after 72 hours of implantation.
Project description:Proteinases play a pivotal role in wound healing by degrading molecular barriers, regulating cell-matrix interactions and availability of bioactive molecules. Matrix metalloproteinase-13 (MMP-13, collagenase-3) is a wide spectrum proteinase. Its expression and function is linked to the growth and invasion of many epithelial cancers such as squamous cell carcinoma. Moreover, the physiologic expression of MMP-13 is associated e.g. to scarless healing of human fetal skin and adult gingival wounds. While MMP-13 is not found in the normally healing skin wounds in human adults, it is expressed in mouse skin during wound healing. Thus, mouse wound healing models can be utilized for studying the role of MMP-13 in the events of wound healing. As the processes such as the migration and proliferation of keratinocytes, angiogenesis, inflammation and activation of fibroblasts are components of wound repair as well as of cancer, many results received from wound healing studies are also adaptable to cancer research. Classically, the process of wound healing can be devided into three phases which are histologically and functionally separate but temporally overlapping: 1) hemostasis and inflammation, 2) re-epithelialization and granulation tissue formation, and 3) matrix remodeling. Granulation tissue is formed into the wound via fibroplasia, angiogenesis and extracellular matrix (ECM) deposition by fibroblasts. Granulation tissue is rich in inflammatory cells, fibroblasts, myofibroblasts and blood vessels. After epidermal recovery, the granulation tissue is resolved via matrix remodeling and cell apoptosis. A sterile viscose cellulose sponge (VCS) characterized by defined size and structure can be used to experimentally induce formation of subcutaneous granulation tissue. Compared to normal granulation tissue, this model allows easy examination of the granulation tissue in its entirety but leaving out epidermal keratinocytes in the sample preparation. In this study, we studied the role of MMP-13 in the formation of mouse VCS-induced granulation tissue. We performed gene expression profiling of the granulation tissue samples of Mmp13-/- (KO) and wild type (WT) mice harvested at day 7, day 14 and day 21 after VCS implantation. Mmp13-/- (KO) mice were generated as described (Inada et al. 2004, PNAS, 101: 17192-17197) and used in these experiments after backcrossing at least seven generations into C57BL6 mice. The WT mice were generated from the backcrossed heterozygote Mmp13-/- (KO) mice. Granulation tissues were harvested at three time points (7d, 14d, 21d) from Mmp13-/- (KO) and WT mice. One sample of each mouse was analyzed (n=3, 7d; n=4, 14d; n=4, 21d; for each genotype). The samples were processed for RNA extraction and Affymetrix 3'IVT DNA microarray gene expression analysis.
Project description:Proteinases play a pivotal role in wound healing by degrading molecular barriers, regulating cell-matrix interactions and availability of bioactive molecules. Matrix metalloproteinase-13 (MMP-13, collagenase-3) is a wide spectrum proteinase. Its expression and function is linked to the growth and invasion of many epithelial cancers such as squamous cell carcinoma. Moreover, the physiologic expression of MMP-13 is associated e.g. to scarless healing of human fetal skin and adult gingival wounds. While MMP-13 is not found in the normally healing skin wounds in human adults, it is expressed in mouse skin during wound healing. Thus, mouse wound healing models can be utilized for studying the role of MMP-13 in the events of wound healing. As the processes such as the migration and proliferation of keratinocytes, angiogenesis, inflammation and activation of fibroblasts are components of wound repair as well as of cancer, many results received from wound healing studies are also adaptable to cancer research. Classically, the process of wound healing can be devided into three phases which are histologically and functionally separate but temporally overlapping: 1) hemostasis and inflammation, 2) re-epithelialization and granulation tissue formation, and 3) matrix remodeling. Granulation tissue is formed into the wound via fibroplasia, angiogenesis and extracellular matrix (ECM) deposition by fibroblasts. Granulation tissue is rich in inflammatory cells, fibroblasts, myofibroblasts and blood vessels. After epidermal recovery, the granulation tissue is resolved via matrix remodeling and cell apoptosis. A sterile viscose cellulose sponge (VCS) characterized by defined size and structure can be used to experimentally induce formation of subcutaneous granulation tissue. Compared to normal granulation tissue, this model allows easy examination of the granulation tissue in its entirety but leaving out epidermal keratinocytes in the sample preparation. In this study, we studied the role of MMP-13 in the formation of mouse VCS-induced granulation tissue. We performed gene expression profiling of the granulation tissue samples of Mmp13-/- (KO) and wild type (WT) mice harvested at day 7, day 14 and day 21 after VCS implantation.
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes
Project description:Few studies have assessed the patterns of parasite populations of rodents over a longitudinal gradient in Chile. In this work, the gastrointestinal helminthic fauna of invasive rodents in Chile was examined to assess the association between their presence/absence and abundance with latitude, host sex, and host body condition, and to assess the coexistence and correlation of the abundance between parasite species. Rodents were obtained from 20 localities between 33 and 43°S. Helminths were extracted from the gastrointestinal tract and identified morphologically. Overall, 13 helminth taxa were obtained. The most frequently identified parasite species was Heterakis spumosa, and the most abundant was Syphacia muris, while Physaloptera sp. was the most widely distributed. No locality presented with a coexistence that was different from that expected by chance, while the abundance of five helminthic species correlated with the abundance of another in at least one locality, most likely due to co-infection rather than interaction. Host sex was associated with parasite presence or abundance, and female sex-biased parasitism was notably observed in all cases. Body condition and latitude presented either a positive or negative association with the presence or abundance of parasites depending on the species. It is notable that the likely native Physaloptera sp. is widely distributed among invasive rodents. Further, gravid females were found, suggesting spillback of this species to the native fauna. The low frequency and abundance of highly zoonotic hymenolepid species suggest that rodents are of low concern regarding gastrointestinal zoonotic helminths.
Project description:Aging causes a functional decline in tissues throughout the body that may be delayed by caloric restriction (CR). However, the cellular profiles and signatures of aging, as well as those ameliorated by CR, remain unclear. Here, we built comprehensive single-cell and single-nucleus transcriptomic atlases across various rat tissues undergoing aging and CR. CR attenuated aging-related changes in cell type composition, gene expression, and core transcriptional regulatory networks. Immune cells were increased during aging, and CR favorably reversed the aging-disturbed immune ecosystem. Computational prediction revealed that the abnormal cell-cell communication patterns observed during aging, including the excessive proinflammatory ligand-receptor interplay, were reversed by CR. Our work provides multi-tissue single-cell transcriptional landscapes associated with aging and CR in a mammal, enhances our understanding of the robustness of CR as a geroprotective intervention, and uncovers how metabolic intervention can act upon the immune system to modify the process of aging.