Quantitative assessment of human uterine fibroid xenograft using sequential in vivo bioluminescence imaging

Uterine fibroid is one of the most common solid tumors occurring in reproductive age women. Lack of accurate methods for quantitative assessment of uterine fibroid progression severely impedes the basic research and drug screen of this disease. To solve this problem, the correlation between bioluminescence imaging (BLI) and initial cell number used to form xenograft was investigated in this study. The results showed that both subcutaneous (SC) and intraperitoneal (IP) D-luciferin administration led to fast increase of bioluminescence signal (BLS) intensity and caused large variation of peak signal intensity of xenografts through the analysis of BLI kinetic curves. We found that a distinct linear stage appeared in xenograft BLI curve for each mouse subjected to IP-injection of D-luciferin. Moreover, a high positive correlation was found between linear slope and the initial number of human uterine fibroid smooth muscle cells (fSMCs) used for xenograft formation. Our research indicates that the slope of linear stage in BLI curve is more appropriate for quantitative assessment of human uterine fibroid xenograft.