High-speed large-scale 4D activities mapping of moving C. elegans by deep-learning-enabled light-field microscopy on a chip

Abstract

We report a novel fusion of microfluidics and light-field microscopy, to achieve high-speed 4D (space + time) imaging of moving C. elegans on a chip. Our approach combines automatic chip-based worm loading / compartmentalization / flushing / reloading with instantaneous deep-learning light-field imaging of moving worm. Taken together, we realized intoto image-based screening of wild-type and uncoordinated-type worms at a volume rate of 33 Hz, with sustained observation of 1 minute per worm, and overall throughput of 42 worms per hour. With quickly yielding over 80000 image volumes that four-dimensionally visualize the dynamics of all the worms, we can quantitatively analyse their behaviours as well as the neural activities, and correlate the phenotypes with the neuron functions. The different types of worms can be readily identified as a result of the high-throughput activity mapping. Our approach shows great potential for various lab-on-a-chip biological studies, such as embryo sorting and cell growth assays.

Adapting and optimizing GCaMP8f for use inCaenorhabditis elegans

“…With faster imaging technologies such as lightfield or lightsheet imaging (Voleti et al 2019;Zhu et al 2021) allowing brain imaging at up to 26 VPS, the true limitation for measurement is frequently the brightness of the indicator rather than the speed of acquisition (Kato et al 2015;Hallinen et al 2021;Atanas et al 2022). Accordingly, faster and brighter indicators would positively impact these measurements in two ways, as they could either enable imaging of neurons driving faster behaviors, such as head swings, pharyngeal pumping and the activity of the spiking motoneurons (Gao and Zhen 2011;Hendricks et al 2012;Trojanowski et al 2016;Atanas et al 2022), or alternatively enable longer measurements due to the lower photobleaching expected.…”