Feasibility Study of Human Corneal Endothelial Cell Transplantation Using an In Vitro Human Corneal Model

Purpose: To test the feasibility of a cell-therapy approach to treat corneal endothelial (CE) disorders using an in vitro model of human corneal decompensation. Materials and Methods: A CE decompensation model was established by removal of the DM/Endothelium complex from human cadaveric corneas in an air-interface organ culture system (Group 2) and compared to normal corneas (Group 1). The posterior stroma of decompensated corneas was seeded with immortalized human corneal endothelial cells (HCEC-12) in Group 3 and passage 0 primary human corneal endothelial cells (hCECs) in Group 4 corneas. Functional effects on stromal thickness were undertaken with histological analysis 3-10 days post-cell therapy treatment. Results: Removal of the DM/Endothelium complex in Group 2 corneas resulted in a stromal thickness of 903 ± 86 μm at 12 hours in comparison to 557 ± 72 μm in Group 1 corneas. The stromal thickness reduced from 1218 ± 153 μm to 458 ± 90 μm (63 ± 6 %, p=0.001) post cell transplantation in Group 3) and from 1100 ± 86 μm to 489 ± 94 μm (55 ± 7 %, p=0.00004 in Group 4 respectively. Post-transplantation histology demonstrated the formation of a monolayer of corneal endothelium attached to the posterior stromal surface. Conclusion: Direct transplantation of cultured hCECs and immortalized HCEC-12 to bare posterior corneal stroma resulted in the formation of an endothelial monolayer and restoration of stromal hydration to physiological thickness, demonstrating the feasibility of cell therapy in the treatment of corneal endothelial decompensation in a human in vitro model

Radiation-induced craniofacial bone growth inhibition: acute and long-term effects on bone histopathology with and without cytoprotection

The authors previously established an animal model of radiation-induced craniofacial bone growth inhibition and demonstrated the effectiveness of cytoprotection in preserving growth using amifostine, but the mechanism is unclear. The objective of this study was to investigate the acute and long-term histopathologic effects of single-dose orthovoltage irradiation on craniofacial bone with and without cytoprotection

Development and Validation of Confocal Endomicroscopy Diagnostic Criteria for Low-Grade Dysplasia in Barrett's Esophagus.

OBJECTIVES: Low-grade dysplasia (LGD) in Barrett's esophagus (BE) is generally inconspicuous on conventional and magnified endoscopy. Probe-based confocal laser endomicroscopy (pCLE) provides insight into gastro-intestinal mucosa at cellular resolution. We aimed to identify endomicroscopic features and develop pCLE diagnostic criteria for BE-related LGD. METHODS: This was a retrospective study on pCLE videos generated in 2 prospective studies. In phase I, 2 investigators assessed 30 videos to identify LGD endomicroscopic features, which were then validated in an independent video set (n = 25). Criteria with average accuracy >80% and interobserver agreement κ > 0.4 were taken forward. In phase II, 6 endoscopists evaluated the criteria in an independent video set (n = 57). The area under receiver operating characteristic curve was constructed to find the best cutoff. Sensitivity, specificity, interobserver, and intraobserver agreements were calculated. RESULTS: In phase I, 6 out of 8 criteria achieved the agreement and accuracy thresholds (i) dark nonround glands, (ii) irregular gland shape, (iii) lack of goblet cells, (iv) sharp cutoff of darkness, (v) variable cell size, and (vi) cellular stratification. The best cutoff for LGD diagnosis was 3 out of 6 positive criteria. In phase II, the diagnostic criteria had a sensitivity and specificity for LGD of 81.9% and 74.6%, respectively, with an area under receiver operating characteristic of 0.888. The interobserver agreement was substantial (κ = 0.654), and the mean intraobserver agreement was moderate (κ = 0.590). CONCLUSIONS: We have generated and validated pCLE criteria for LGD in BE. Using these criteria, pCLE diagnosis of LGD is reproducible and has a substantial interobserver agreement.Financial support: the Addenbrookes Charitable Trust and the Kathy Shaw Memorial (Oesophageal Cancer) Fund funded the endoscopy equipment at Cambridge University Hospital. This study received infrastructure support from the Experimental Cancer Medicine Center and from the Cambridge Cancer Centre