Longitudinal high-resolution imaging through a flexible intravital imaging window

Abstract

Intravital microscopy (IVM) is a powerful technique that enables imaging of internal tissues at (sub)cellular resolutions in living animals. Here, we present a silicone-based imaging window consisting of a fully flexible, sutureless design that is ideally suited for long-term, longitudinal IVM of growing tissues and tumors. Crucially, we show that this window, without any customization, is suitable for numerous anatomical locations in mice using a rapid and standardized implantation procedure. This low-cost device represents a substantial technological and performance advance that facilitates intravital imaging in diverse contexts in higher organisms, opening previously unattainable avenues for in vivo imaging of soft and fragile tissues.

In vivo imaging of mammary epithelial cell dynamics in response to lineage-biased Wnt/β-catenin activation

“…To visualize cellular dynamics in vivo and in situ during mammary ductal development, we surgically implanted an imaging window (Jacquemin et al, 2021;Zomer et al, 2013) over the abdominal (fourth) mammary gland of 5/6-week-old pubertal mice, 24-72 h after Cre induction (Figure 1E). This approach enabled the high-resolution 4-dimensional (x, y, z, and t) intravital imaging of the mammary epithelium over time in physiological conditions.…”

Monitoring and modulation of the tumor microenvironment for enhanced cancer modeling

“…166,[172][173][174][175] Further work in this direction has aimed at extending experiment duration through the integration of fluidic control with intravital imaging windows (ported mammary imaging window) (Figure 3(i)). 63,176 Recently, the development of integrated micro-nozzles for enhanced control over localized delivery has provided additional impetus for high resolution study in vivo (Figure 3(j)). 177 Genome editing to manipulate the TME.…”

Imaging the different timescales of germinal center selection*

“…A common theme for many of these sensors is the events they report on (such as the cell cycle or the “turning on” of a gene) do not always fit easily into the timeframe of imaging or the length of time for which an individual cell can be tracked. Technical improvements, for instance in surgical imaging windows, 95 as well as recent feats in high resolution imaging of neuroactivity that have allowed simultaneous recording of up to 1 000 000 neurons in the mouse cortex, 104 give a glimpse of what could be achieved by MPLSM in coming years. Ultimately, the goal of tracking brief signaling events in individual cells for several hours at a time, over the entire life course of a GC, appears to be within reach.…”

“…The current set‐up for longitudinal single GC imaging is restricted in time to around 20 days, 94 which is shorter than the lifetime of most immunization‐induced GCs. This imaging period could be extended by a novel form of polydimethylsiloxane (PDMS)‐based window implants, 95 recently developed for the long‐term imaging of growing tissues such as tumors. These windows do not require suture attachment and can substitute the current glass coverslip with PDMS.…”