Publications

The purpose of this study was to establish a method for the fabrication of exogenous gene-transferred, transplantable corneal epithelial cell sheets. Corneo-limbal epithelial cells collected from USA eye bank eyes were transduced with an EGFP-expressing lentiviral vector at differential MOI. Multi-layered corneal epithelial cell sheets were fabricated by co-cultivation of transduced cells and mitomycin C-treated 3T3 feeder layers on temperature-responsive culture dishes. These cultured epithelial cells could be harvested as intact sheets by simply lowering the temperature. The number of EGFP-positive cells was increased as the MOI raised, and at an MOI of 100, nearly 100% of the superficial cells showed strong EGFP expression. Histological analysis revealed that EGFP was expressed in all layers of the cell sheet of which cell source was transduced with the lentiviral vector at an MOI of 100. Immunofluorescence data showed that p63 was also expressed in the basal layer of the same cell sheet. These results suggest that this technique will likely be applicable to ex vivo gene therapies for various corneal disorders.

BACKGROUND

Regional differences in fibrosis, particularly related to the posterior wall and septum, may be important in atrial fibrillation (AF). Using electroanatomic mapping, voltage can be used as a measure of fibrosis.

OBJECTIVES

The purpose of this study was to determine if patients with AF have disproportionately lower voltage in the septal and posterior walls of the left atrium.

METHODS

Sinus rhythm left atrial electroanatomic maps were used in serial patients presenting for left atrial ablation of AF (8-mm tip). Patients undergoing left atrial mapping for focal atrial tachycardia (AT) were used as a comparison group (4-mm tip). Animal experiments were performed to assess the influence of ablation catheter tip size on voltage amplitude.

RESULTS

The posterior and septal walls exhibited the lowest voltages in both groups. Compared with the anterior wall, there was a 3.78-fold greater odds of finding a low-voltage point (<0.5 mV) in the septum (P <.001) and a 3.37-fold greater odds of finding a low-voltage point in the posterior wall (P <.001) in the AF patients; the proportion of low-voltage points by region were not significantly different in the AT group. In the animal model, the mean voltage obtained from an 8-mm ablation catheter was significantly higher (0.30 +/- 0.17 mV) than that obtained from the same points using a 4-mm catheter (0.22 +/- 0.17, P = .05).

CONCLUSION

Regional differences in voltage are present in patients with atrial arrhythmias, with AF patients exhibiting significantly more low-voltage areas in the septum and posterior walls.

BACKGROUND & AIMS

Biliary-directed inflammation is an important cause of acute and chronic liver disease. We developed and characterized a transgenic mouse model of immune-mediated hepatobiliary injury.

METHODS

Ovalbumin (OVA)-BIL mice were developed using 3.0 kilobase of the rat apical sodium-dependent bile acid transporter promoter to drive aberrant expression of a membrane form of ovalbumin (OVA) on biliary epithelium. Liver inflammation resulted from adoptive transfer of OVA-specific T cells. Liver immune cells were characterized to determine the mechanism of the response by assessing activation, proliferation, and intracellular cytokine expression.

RESULTS

OVA-BIL transgenic mice were tolerant to OVA, without evidence of liver disease. Adoptive transfer of OVA-specific CD4+ and CD8+ T cells into naïve OVA-BIL mice led to biliary-centered necroinflammatory damage in a dose-dependent manner. This inflammation absolutely required CD8+ T cells and was augmented by CD4+ T cells. Adoptively transferred OVA CD8+ cells homed to and proliferated in the liver but not the spleen. These activated, adoptively transferred cytotoxic T lymphocytes produced elevated levels of tumor necrosis factor alpha and interferon gamma.

CONCLUSIONS

T-cell recognition of antigen aberrantly expressed on bile duct epithelium induced an acute necroinflammatory response specific to the liver, with activation, proliferation, and cytokine production predominantly by the OVA-specific cytotoxic T cells. Thus, OVA BIL represents an antigen-specific animal model of inflammatory bile duct injury.