Establishment of repeated liver biopsy technique in experimental mice.

Biopsy is a commonly used method for determining pathological diagnoses by directly using human tissues and cells. Biopsies are widely used to determine disease progression and treatment efficacy. Although organs and tissues are usually obtained by sacrifice during animal experiments, it is theoretically possible to use the same biopsy techniques in humans. In the present study, we examined the feasibility of performing four repeated liver biopsies in a spontaneous metabolic syndrome mouse model. Even though a small number of mice died accidently, most mice were able to undergo four liver biopsies without significant adverse events. We also performed three liver biopsies in mouse liver tumor carcinogen models at 4, 8, and 12 weeks of age. In addition to the sample collected at 16 weeks of age during sacrifice, we successfully collected four liver samples from the same mice at different stages of disease progression. The application of this liver biopsy technique might make it possible for direct evaluation of pathological conditions in the same individual over time, thereby reducing the number of experimental animals.