EVALUATION OF THE STRUCTURE AND COMPOSITION OF THE TIBIA IN TPC2KO GENETICALLY EDITED PIGS
Supporting Agencies
- Fundación Séneca–Agencia de Ciencia y Tecnología de la Región de Murcia
Abstract
Bone tissue is a dynamic system regulated by the balance between bone formation and resorption, processes in which intracellular calcium signaling plays a crucial role. The lysosomal ion channel TPC2 is involved in these mechanisms, particularly in osteoclastogenesis, although its role in porcine models remains poorly understood. The aim of this study was to evaluate the effect of TPC2 gene deletion on bone structure and composition in the tibia of genetically edited pigs (TPC2KO) compared to wild-type (WT) controls. Tibias from 12 animals (6 per group) were analysed using micro-computed tomography (micro-CT), scanning electron microscopy (SEM), cortical texture analysis (GLCM), and energy-dispersive X-ray spectroscopy (SEM-EDX). Micro-CT results showed that TPC2KO animals had significantly increased bone volume, bone volume fraction (BV/TV), and trabecular thickness. No significant differences were found in trabecular spacing or connectivity indices. SEM observations revealed a more compact and homogeneous cortical structure in KO animals, which was supported by GLCM analysis indicating reduced structural complexity. Elemental analysis showed a significant increase in magnesium content in TPC2KO animals, while calcium and phosphorus levels remained unchanged. This suggests a less mature and more dynamic mineralization process. Overall, TPC2 deletion alters both bone microarchitecture and mineral composition, likely due to changes in osteoclastogenesis and calcium signaling. These findings highlight the relevance of the TPC2KO porcine model for studying bone physiology.
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