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Daniel Weng - One of the best experts on this subject based on the ideXlab platform.
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role of p38 map kinase in regulation of cell migration and proliferation in healing Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira Ooshima, Osalnu Yamanaka, Daniel WengAbstract:PURPOSE: The purpose of the present study was to examine the roles of signaling pathways potentially activated by TGFbeta (i.e., Smad and p38 mitogen-activated kinase [MAPK]) in regulation of cell migration and proliferation of healing mouse Corneal Epithelium. METHODS: Activation of Smads or p38MAPK was evaluated by immunohistochemistry in healing mouse Corneal Epithelium after debridement. The role of endogenous TGFbeta or p38MAPK in epithelial healing was determined in organ-cultured mouse corneas with an epithelial defect, in the presence or absence of a TGFbeta-neutralizing antibody or p38MAPK inhibitors, respectively. Cell proliferation was evaluated by incorporation of bromodeoxyuridine. RESULTS: Migrating mouse Corneal Epithelium had minimal cell proliferation. Smad3 and -4 were found in nuclei of normal Corneal Epithelium, whereas they were absent in nuclei of migrating cells in association with Smad7 upregulation on epithelial debridement. Administration of TGFbeta-neutralizing antibody reduced the protein expression of Smad7 in vivo after a Corneal injury. In contrast, phosphorylation and nuclear translocation of p38MAPK were markedly evident in migrating Epithelium during healing, but not in uninjured Epithelium. In organ culture, addition of p38MAPK inhibitors blocked cell migration more markedly than neutralizing TGFbeta-antibody and enhanced cell proliferation in the injured Corneal Epithelium, in association with phosphorylation of Erk. CONCLUSIONS: Endogenous TGFbeta enhances migration of Corneal Epithelium during wound healing in mice. The p38MAPK, but not the Smad, cascade plays a major role in promoting cell migration and in suppressing cell proliferation in migrating Epithelium.
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Role of p38 MAP kinase in regulation of cell migration and proliferation in healing Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira Ooshima, Osalnu Yamanaka, Daniel WengAbstract:PURPOSE. The purpose of the present study was to examine the roles of signaling pathways potentially activated by TGFβ (i.e., Smad and p38 mitogen-activated kinase [MAPK]) in regulation of cell migration and proliferation of healing mouse Corneal Epithelium. METHODS. Activation of Smads or p38MAPK was evaluated by immunohistochemistry in healing mouse Corneal Epithelium after debridement. The role of endogenous TGFβ or p38MAPK in epithelial healing was determined in organ-cultured mouse corneas with an epithelial defect, in the presence or absence of a TGFβ-neutralizing antibody or p38MAPK inhibitors, respectively. Cell proliferation was evaluated by incorporation of bromodeoxyuridine. RESULTS. Migrating mouse Corneal Epithelium had minimal cell proliferation. Smad3 and -4 were found in nuclei of normal Corneal Epithelium, whereas they were absent in nuclei of migrating cells in association with Smad7 upregulation on epithelial debridement. Administration of TGFβ-neutmlizing antibody reduced the protein expression of Smad7 in vivo after a Corneal injury. In contrast, phosphorylation and nuclear translocation of p38MAPK were markedly evident in migrating Epithelium during healing, but not in uninjured Epithelium. In organ culture, addition of p38MAPK inhibitors blocked cell migration more markedly than neutralizing TGFβ-antibody and enhanced cell proliferation in the injured Corneal Epithelium, in association with phosphorylation of Erk. CONCLUSIONS. Endogenous TGFβ enhances migration of Corneal Epithelium during wound healing in mice. The p38MAPK, but not the Smad, cascade plays a major role in promoting cell Epithelium.
Shizuya Saika - One of the best experts on this subject based on the ideXlab platform.
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Lack of plakoglobin impairs integrity and wound healing in Corneal Epithelium in mice
Laboratory Investigation, 2018Co-Authors: Masahide Kokado, Yuka Okada, Masayasu Miyajima, Kana Ichikawa, Osamu Yamanaka, Weinian Shou, Shizuya SaikaAbstract:We generated cornea-specific plakoglobin (Jup; junctional plakoglobin) knockout mice in order to investigate the function of plakoglobin on the maintenance of the homeostasis of Corneal Epithelium in mice. Cornea Epithelium-specific conditional knockouts (Jup CEΔ/CEΔ ) (cKO) were obtained by breeding keratin12-Cre (Krt12-Cre) mice to Jup-floxed (Jup f/f ) mice. Light and transmission electron microscopic and immunohistochemical analyses were carried out to determine consequence of the loss of plakoglobin on maintaining Corneal Epithelium integrity under mechanical stress, e.g., brushing and wound healing. Immunohistochemistry analysis demonstrated that, although Jup ablation did not affect BrdU incorporation, basal cell-like cells labeled for keratin 14 were ectopically present in the supra-basal layer in mutant Corneal Epithelium, suggestive of altered cell differentiation. Plakoglobin-deficient Epithelium exhibits increased fragility against mechanical intervention when compared to wild-type controls under identical treatment. Closure of an epithelial defect was significantly delayed in Jup CEΔ/CEΔ Epithelium. Our findings indicate that the lack of plakoglobin significantly affects Corneal Epithelium differentiation, as well as its structural integrity. Plakoglobin is essential to the maintenance of the structure of the Corneal Epithelium and its wound healing.
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Sonic hedgehog expression and role in healing Corneal Epithelium.
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yasuteru Muragaki, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira OoshimaAbstract:PURPOSE. To examine the expression pattern and roles of Sonic hedgehog (Shh) in healing Corneal Epithelium. METHODS. Immunofluorescent staining and Western blot analysis were used to detect Shh, patched 1 (Ptc 1) receptors, and Gli transcription factors in Corneal Epithelium of Wistar rats (n = 44) at various intervals after an epithelial defect. Effects of exogenous Shh on cell proliferation and cyclin D1 expression were determined in healing Corneal Epithelium of organ-cultured mouse eyes. RESULTS. Uninjured rat Corneal Epithelium was not labeled by anti-Shh antibody, but weakly positive for Ptc 1. Basal cells of limbal and conjunctival epithelia were labeled by antibodies against Shh and Ptc 1. Shh protein was transiently upregulated in limbal Epithelium in 2 hours and was also transiently expressed in the migrating Corneal Epithelium with its peak at 12 hours postdebridement. Such upregulation of Shh expression was associated with a transient nuclear translocation of Gli-3 without lifting the suppression of cell proliferation in migrating Epithelium postdebridement in vivo. However, an addition of Shh protein to culture medium resulted in nuclear accumulation of cyclin D1 and marked acceleration of epithelial cell proliferation in migrating Corneal Epithelium of an organ-cultured mouse eye. CONCLUSIONS. Corneal epithelial debridement causes a transient upregulation of Shh expression and activation of Shh/Gli-3 signaling cascade in healing Corneal and limbal epithelia. Although exogenous Shh promotes epithelial cell proliferation in Corneal organ culture, its expression in migrating Epithelium in vivo does not counteract the suppression of cell proliferation at the early healing phase of Epithelium debridement.
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role of p38 map kinase in regulation of cell migration and proliferation in healing Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira Ooshima, Osalnu Yamanaka, Daniel WengAbstract:PURPOSE: The purpose of the present study was to examine the roles of signaling pathways potentially activated by TGFbeta (i.e., Smad and p38 mitogen-activated kinase [MAPK]) in regulation of cell migration and proliferation of healing mouse Corneal Epithelium. METHODS: Activation of Smads or p38MAPK was evaluated by immunohistochemistry in healing mouse Corneal Epithelium after debridement. The role of endogenous TGFbeta or p38MAPK in epithelial healing was determined in organ-cultured mouse corneas with an epithelial defect, in the presence or absence of a TGFbeta-neutralizing antibody or p38MAPK inhibitors, respectively. Cell proliferation was evaluated by incorporation of bromodeoxyuridine. RESULTS: Migrating mouse Corneal Epithelium had minimal cell proliferation. Smad3 and -4 were found in nuclei of normal Corneal Epithelium, whereas they were absent in nuclei of migrating cells in association with Smad7 upregulation on epithelial debridement. Administration of TGFbeta-neutralizing antibody reduced the protein expression of Smad7 in vivo after a Corneal injury. In contrast, phosphorylation and nuclear translocation of p38MAPK were markedly evident in migrating Epithelium during healing, but not in uninjured Epithelium. In organ culture, addition of p38MAPK inhibitors blocked cell migration more markedly than neutralizing TGFbeta-antibody and enhanced cell proliferation in the injured Corneal Epithelium, in association with phosphorylation of Erk. CONCLUSIONS: Endogenous TGFbeta enhances migration of Corneal Epithelium during wound healing in mice. The p38MAPK, but not the Smad, cascade plays a major role in promoting cell migration and in suppressing cell proliferation in migrating Epithelium.
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Role of p38 MAP kinase in regulation of cell migration and proliferation in healing Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira Ooshima, Osalnu Yamanaka, Daniel WengAbstract:PURPOSE. The purpose of the present study was to examine the roles of signaling pathways potentially activated by TGFβ (i.e., Smad and p38 mitogen-activated kinase [MAPK]) in regulation of cell migration and proliferation of healing mouse Corneal Epithelium. METHODS. Activation of Smads or p38MAPK was evaluated by immunohistochemistry in healing mouse Corneal Epithelium after debridement. The role of endogenous TGFβ or p38MAPK in epithelial healing was determined in organ-cultured mouse corneas with an epithelial defect, in the presence or absence of a TGFβ-neutralizing antibody or p38MAPK inhibitors, respectively. Cell proliferation was evaluated by incorporation of bromodeoxyuridine. RESULTS. Migrating mouse Corneal Epithelium had minimal cell proliferation. Smad3 and -4 were found in nuclei of normal Corneal Epithelium, whereas they were absent in nuclei of migrating cells in association with Smad7 upregulation on epithelial debridement. Administration of TGFβ-neutmlizing antibody reduced the protein expression of Smad7 in vivo after a Corneal injury. In contrast, phosphorylation and nuclear translocation of p38MAPK were markedly evident in migrating Epithelium during healing, but not in uninjured Epithelium. In organ culture, addition of p38MAPK inhibitors blocked cell migration more markedly than neutralizing TGFβ-antibody and enhanced cell proliferation in the injured Corneal Epithelium, in association with phosphorylation of Erk. CONCLUSIONS. Endogenous TGFβ enhances migration of Corneal Epithelium during wound healing in mice. The p38MAPK, but not the Smad, cascade plays a major role in promoting cell Epithelium.
Nobuyuki Ebihara - One of the best experts on this subject based on the ideXlab platform.
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distinct populations of dendritic cells in the normal human donor Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2005Co-Authors: Satoru Yamagami, Seiichi Yokoo, Tomohiko Usui, Hiroko Yamagami, Shiro Amano, Nobuyuki EbiharaAbstract:PURPOSE: To characterize dendritic cells (DC) in normal human Corneal Epithelium. METHODS: Normal human donor Corneal Epithelium was examined by fluorescence microscopy with single and double staining for multiple markers. Morphologic studies were also performed by confocal microscopy. HLA-DRa, CD1c, and CD16 mRNA expression in the Corneal Epithelium was examined by RT-PCR. CD45+ cells were separated from the Corneal Epithelium with magnetic beads and then were stimulated with TNF-alpha and lipopolysaccharide in vitro. RESULTS: CD45+ cells were mainly located in the basal-cell layer of the Corneal Epithelium and partly in the wing/surface layers. CD45-positive cell numbers were significantly higher in the peripheral cornea (3-6 mm from the center) than in the central cornea (0-3 mm from the center). All these cells expressed HLA-DR and CD11c but not CD3, CD11b, CD14, CD19, CD56, or CD66, suggesting that these were bone marrow-derived myeloid DC. Some DR+CD11c+ DCs from the periphery expressed CD1c and CD16. HLA-DRa, CD1c, and CD16 mRNAs were detected in normal Corneal Epithelium. These CD11c+ DCs did not express CD123, CD1a, DC marker (CMRF56), CD40, CD80, or CD86. When CD45+ cells were isolated from the Corneal Epithelium by magnetic cell sorting, CD40 and CD86 expression were detected after in vitro stimulation with TNF-alpha and lipopolysaccharide. CONCLUSIONS: These findings demonstrate that normal human Corneal Epithelium contains at least three DC phenotypes, with HLA-DR+ myeloid lineage CD11c+CD16- DCs as the main population plus a small number of CD11c+CD16+ DCs and CD11c+CD1c+ DCs. These cells can be discriminated from bone marrow-derived cells in the human Corneal stroma.
Inge Kjonniksen - One of the best experts on this subject based on the ideXlab platform.
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Impact of the environment on the mammalian Corneal Epithelium.
Investigative Ophthalmology & Visual Science, 2003Co-Authors: Amund Ringvold, Erlend Anderssen, Inge KjonniksenAbstract:PURPOSE. To evaluate whether the content of ascorbic acid in the Corneal Epithelium and aqueous humor reflects seasonal fluctuations in parallel with environmental changes. METHODS. Reindeer, cattle, rabbits, and humans were examined, to cover a broad spectrum of overlapping habitats. Ascorbic acid was determined by high-performance liquid chromatography. The thickness of the Corneal Epithelium was measured, and the number of cells was counted in the tissue sections. RESULTS. Three groups of reindeer eyes were used, two of them collected during summer, the third group during winter. Ascorbate content did not show seasonal variation in either the Corneal Epithelium or the aqueous humor, whereas epithelial thickness and number of cells decreased significantly from summer to winter. In cattle, ascorbate content, thickness of the Epithelium, and number of cells were lower in animals tended indoors compared with those tended outdoors, whereas ascorbate level in the aqueous humor remained similar in both cases. The rabbit showed significantly reduced ascorbate content in the Corneal Epithelium but not in the aqueous humor in tarsorrhaphy-treated eyes. This procedure did not change epithelial thickness, but the number of cells was slightly increased. The mean epithelial thickness in human corneas successively decreased with increasing latitude and decreasing radiation exposure from the summer season in Oslo to the midnight sun, polar night, conditions in Tromso, 10° far north, although the differences did not reach statistical significance. CONCLUSIONS. Ambient radiation is needed to sustain high ascorbic acid concentration in the Corneal Epithelium. Corneal epithelial thickness and number of cells are prone to seasonal fluctuations regulated by ambient radiation. In contrast, ascorbate content of the aqueous humor is uninfluenced by environmental change. It is suggested that seasonal adaptation of mammalian Corneal Epithelium in response to variation in ambient radiation may be nature’s strategy for countering radiation damage to the eye. (Invest Ophthalmol Vis Sci. 2003; 44:10 ‐15) DOI:10.1167/iovs.02-0173
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ascorbate in the Corneal Epithelium of diurnal and nocturnal species
Investigative Ophthalmology & Visual Science, 1998Co-Authors: Amund Ringvold, Erlend Anderssen, Inge KjonniksenAbstract:PURPOSE. To compare the amount of ascorbic acid in the Corneal Epithelium of various species to unveil possible differences between diurnal and nocturnal mammals. METHODS. Ascorbic acid was determined by high-performance liquid chromatography, using an LC-10 system (Shimadzu, Kyoto, Japan). RESULTS. Diurnal animals show a higher ascorbate concentration in the Corneal Epithelium than nocturnal animals. Ascorbate concentration is higher in the Corneal Epithelium than in the matching aqueous humor in diurnal and nocturnal species. The highest ascorbate concentration is found in the Corneal Epithelium of the reindeer. CONCLUSIONS. Ascorbate level in the Corneal Epithelium seems to vary in accordance with ambient radiation exposure of the respective species, just as in the aqueous humor. Both phenomena are regarded as environmental adaptations, and the ascorbic acid is suggested as protecting against photokeratitis and as acting as an ultraviolet filter for internal eye structures.
Yuka Okada - One of the best experts on this subject based on the ideXlab platform.
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Lack of plakoglobin impairs integrity and wound healing in Corneal Epithelium in mice
Laboratory Investigation, 2018Co-Authors: Masahide Kokado, Yuka Okada, Masayasu Miyajima, Kana Ichikawa, Osamu Yamanaka, Weinian Shou, Shizuya SaikaAbstract:We generated cornea-specific plakoglobin (Jup; junctional plakoglobin) knockout mice in order to investigate the function of plakoglobin on the maintenance of the homeostasis of Corneal Epithelium in mice. Cornea Epithelium-specific conditional knockouts (Jup CEΔ/CEΔ ) (cKO) were obtained by breeding keratin12-Cre (Krt12-Cre) mice to Jup-floxed (Jup f/f ) mice. Light and transmission electron microscopic and immunohistochemical analyses were carried out to determine consequence of the loss of plakoglobin on maintaining Corneal Epithelium integrity under mechanical stress, e.g., brushing and wound healing. Immunohistochemistry analysis demonstrated that, although Jup ablation did not affect BrdU incorporation, basal cell-like cells labeled for keratin 14 were ectopically present in the supra-basal layer in mutant Corneal Epithelium, suggestive of altered cell differentiation. Plakoglobin-deficient Epithelium exhibits increased fragility against mechanical intervention when compared to wild-type controls under identical treatment. Closure of an epithelial defect was significantly delayed in Jup CEΔ/CEΔ Epithelium. Our findings indicate that the lack of plakoglobin significantly affects Corneal Epithelium differentiation, as well as its structural integrity. Plakoglobin is essential to the maintenance of the structure of the Corneal Epithelium and its wound healing.
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Sonic hedgehog expression and role in healing Corneal Epithelium.
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yasuteru Muragaki, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira OoshimaAbstract:PURPOSE. To examine the expression pattern and roles of Sonic hedgehog (Shh) in healing Corneal Epithelium. METHODS. Immunofluorescent staining and Western blot analysis were used to detect Shh, patched 1 (Ptc 1) receptors, and Gli transcription factors in Corneal Epithelium of Wistar rats (n = 44) at various intervals after an epithelial defect. Effects of exogenous Shh on cell proliferation and cyclin D1 expression were determined in healing Corneal Epithelium of organ-cultured mouse eyes. RESULTS. Uninjured rat Corneal Epithelium was not labeled by anti-Shh antibody, but weakly positive for Ptc 1. Basal cells of limbal and conjunctival epithelia were labeled by antibodies against Shh and Ptc 1. Shh protein was transiently upregulated in limbal Epithelium in 2 hours and was also transiently expressed in the migrating Corneal Epithelium with its peak at 12 hours postdebridement. Such upregulation of Shh expression was associated with a transient nuclear translocation of Gli-3 without lifting the suppression of cell proliferation in migrating Epithelium postdebridement in vivo. However, an addition of Shh protein to culture medium resulted in nuclear accumulation of cyclin D1 and marked acceleration of epithelial cell proliferation in migrating Corneal Epithelium of an organ-cultured mouse eye. CONCLUSIONS. Corneal epithelial debridement causes a transient upregulation of Shh expression and activation of Shh/Gli-3 signaling cascade in healing Corneal and limbal epithelia. Although exogenous Shh promotes epithelial cell proliferation in Corneal organ culture, its expression in migrating Epithelium in vivo does not counteract the suppression of cell proliferation at the early healing phase of Epithelium debridement.
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role of p38 map kinase in regulation of cell migration and proliferation in healing Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira Ooshima, Osalnu Yamanaka, Daniel WengAbstract:PURPOSE: The purpose of the present study was to examine the roles of signaling pathways potentially activated by TGFbeta (i.e., Smad and p38 mitogen-activated kinase [MAPK]) in regulation of cell migration and proliferation of healing mouse Corneal Epithelium. METHODS: Activation of Smads or p38MAPK was evaluated by immunohistochemistry in healing mouse Corneal Epithelium after debridement. The role of endogenous TGFbeta or p38MAPK in epithelial healing was determined in organ-cultured mouse corneas with an epithelial defect, in the presence or absence of a TGFbeta-neutralizing antibody or p38MAPK inhibitors, respectively. Cell proliferation was evaluated by incorporation of bromodeoxyuridine. RESULTS: Migrating mouse Corneal Epithelium had minimal cell proliferation. Smad3 and -4 were found in nuclei of normal Corneal Epithelium, whereas they were absent in nuclei of migrating cells in association with Smad7 upregulation on epithelial debridement. Administration of TGFbeta-neutralizing antibody reduced the protein expression of Smad7 in vivo after a Corneal injury. In contrast, phosphorylation and nuclear translocation of p38MAPK were markedly evident in migrating Epithelium during healing, but not in uninjured Epithelium. In organ culture, addition of p38MAPK inhibitors blocked cell migration more markedly than neutralizing TGFbeta-antibody and enhanced cell proliferation in the injured Corneal Epithelium, in association with phosphorylation of Erk. CONCLUSIONS: Endogenous TGFbeta enhances migration of Corneal Epithelium during wound healing in mice. The p38MAPK, but not the Smad, cascade plays a major role in promoting cell migration and in suppressing cell proliferation in migrating Epithelium.
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Role of p38 MAP kinase in regulation of cell migration and proliferation in healing Corneal Epithelium
Investigative Ophthalmology & Visual Science, 2004Co-Authors: Shizuya Saika, Yuka Okada, Takeshi Miyamoto, Yoshitaka Ohnishi, Akira Ooshima, Osalnu Yamanaka, Daniel WengAbstract:PURPOSE. The purpose of the present study was to examine the roles of signaling pathways potentially activated by TGFβ (i.e., Smad and p38 mitogen-activated kinase [MAPK]) in regulation of cell migration and proliferation of healing mouse Corneal Epithelium. METHODS. Activation of Smads or p38MAPK was evaluated by immunohistochemistry in healing mouse Corneal Epithelium after debridement. The role of endogenous TGFβ or p38MAPK in epithelial healing was determined in organ-cultured mouse corneas with an epithelial defect, in the presence or absence of a TGFβ-neutralizing antibody or p38MAPK inhibitors, respectively. Cell proliferation was evaluated by incorporation of bromodeoxyuridine. RESULTS. Migrating mouse Corneal Epithelium had minimal cell proliferation. Smad3 and -4 were found in nuclei of normal Corneal Epithelium, whereas they were absent in nuclei of migrating cells in association with Smad7 upregulation on epithelial debridement. Administration of TGFβ-neutmlizing antibody reduced the protein expression of Smad7 in vivo after a Corneal injury. In contrast, phosphorylation and nuclear translocation of p38MAPK were markedly evident in migrating Epithelium during healing, but not in uninjured Epithelium. In organ culture, addition of p38MAPK inhibitors blocked cell migration more markedly than neutralizing TGFβ-antibody and enhanced cell proliferation in the injured Corneal Epithelium, in association with phosphorylation of Erk. CONCLUSIONS. Endogenous TGFβ enhances migration of Corneal Epithelium during wound healing in mice. The p38MAPK, but not the Smad, cascade plays a major role in promoting cell Epithelium.