Applicability of gas vesicles isolated from Halobacterium salinarum as contrast agents for renal evaluation in rabbits using contrast-enhanced ultrasound and super-resolution

• Grant number: 24/01809-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2024
• End date: August 31, 2026
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Marcus Antônio Rossi Feliciano
• Grantee: Gabriela Castro Lopes Evangelista
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil

Abstract

Contrast-enhanced ultrasound (CEUS) is an emerging technique in vascular assessment with diagnostic and therapeutic applications. Despite promising results in clinical imaging, there are limitations for application in molecular imaging. Gas vesicles (GVs) produced by some species of bacteria and archaea are presented as a new class of ultrasound contrast agents with potential for molecular imaging. The objective of this study is to evaluate the efficacy and safety of GVs extracted from H. salinarum as contrast agents through in vitro and in vivo tests in the renal evaluation of healthy rabbits, using CEUS and super-resolution ultrasound (SRUS). Thirty-two rabbits divided into four experimental groups will be evaluated: group 1 (G1 - n = 8) rabbits submitted to SRUS with commercial contrast; group 2 (G2 - n = 8) rabbits subjected to SRUS with GVs extracted from H. salinarum; group 3 (G3 - n = 8) rabbits submitted to CEUS with commercial contrast; and group 4 (G4 - n = 8) rabbits submitted to CEUS with GVs extracted from H. salinarum. The data will be evaluated following the guidelines for the safety and efficacy of drugs in animals. Perfusion parameters, enhancement and vascular architecture will be evaluated using videos and images obtained by CEUS and SRUS techniques. For statistical analyses, a significance level of 5% (p <0.05) will be set in all tests.