Longitudinal monitoring of tumor cell migration and angiogenesis in the biomaterial scaffold in vivo (Conference Presentation)

Here we introduce a multidisciplinary approach combining biomaterial scaffold, gold nanoparticle (AuNP) labelling and photoacoustic microscopy (PAM) for longitudinal tracking of tumor cell migration and tumor-induced angiogenesis via a flexible, intravital imaging window. Firstly, scaffold with special landmark design was implanted to mouse body forming a synthetic metastatic niche, and tumor with strong metastatic capability was inoculated to induce the primary tumor. When the primary tumor was fully developed, cardiac injection of 4T1 cells labeled with spherical AuNPs was conducted to trigger the metastasis of these cells to scaffold area. Dual-wavelength PAM imaging, using 635 nm to specifically observe AuNPs and 532 nm for vascular imaging, was performed every 24 hours to track the migration of labeled cells at single-cell resolution and to capture vasculature progression simultaneously. In addition, optical coherence tomography (OCT) was applied to visualize the entire microenvironment within scaffold, providing landmark reference for image co-registration.