The Stress-Chip: A microfluidic platform for stress analysis in Caenorhabditis elegans

Abstract

An organism’s ability to mount a physiological response to external stressors is fundamental to its interaction with the environment. Experimental exploration of these interactions benefits greatly from the ability to maintain tight control of the environment, even under conditions in which it would be normal for the subject to flee the stressor. Here we present a nematode research platform that pairs automated image acquisition and analysis with a custom microfluidic device. This platform enables tight environmental control in low-density, single-worm arenas, which preclude animal escape while still allowing a broad range of behavioral activities. The platform is easily scalable, with two 50 arena arrays per chip and an imaging capacity of 600 animals per scanning device. Validating the device using dietary, osmotic, and oxidative stress indicates that it should be of broad use as a research platform, including eventual adaptation for additional stressors, anthelmintic-drug screening, and toxicology studies.

Automated Lifespan Determination Across Caenorhabditis Strains and Species Reveals Assay-Specific Effects of Chemical Interventions

“…All nematode culturing was done at 20 °C. Experimental temperatures were verified using previously used temperature data loggers or custom 16-channel temperature recorders (Banse et al 2019).…”

A naturally segregating polymorphism balancing semelparous reproduction versus reproductive diapause revealed via microfluidic assessment of starvation stress inCaenorhabditis elegans

“…Lifespan assays of C. elegans using the same constriction point in a similar device but done in the presence of food result in a normal lifespan suggesting the passage of worms through the constriction point in this manner does not result in injury (Banse, Blue, Robinson, Jarrett, & Phillips, 2019).…”

“…The Starvation Arena ( Figure 2) was designed with Vectorworks Fundamentals (Vectorworks, Inc.). Using standard soft lithography methods (Whitesides, Ostuni, Takayama, Jiang, & Ingber, 2001), single layer devices were fabricated with polydimethylsiloxane (PDMS) and bonded to a glass microscopy slide by air plasma exposure (see Banse, Blue, Robinson, Jarrett, & Phillips, 2019). A biopsy punch was used to open inlet and outlet channels.…”

“…The amount of labor required by these assays also limits the throughput and temporal resolution, such that most assays performed with larger samples are conducted with population cohorts and lack individual longitudinal information. Here, we develop a microfluidics approach that allows individual responses to be assayed at high temporal resolution using an automated scanner-based image acquisition system (based on Banse, Blue, Robinson, Jarrett, & Phillips, 2019). We are able to standardize the environment by using constant perfusion to flush metabolic byproducts and use an artificial dirt (pillared) structure (Lockery et al, 2008) so as to allow worms to display plate-like behavior and physiology.…”

An open source microfluidic sorter for Caenorhabditis nematodes

“…PDMS is non-toxic, oxygen permeable, and optically transparent, making it particularly attractive for use with nematodes. PDMS-based microfluidic chips have been used in a wide range of nematode research applications [3,4], including image-based screening [5][6][7][8][9][10], assaying lifespan [11], stress resistance [12], and reproduction [13], analyzing neurophysiology and behavior [11,[14][15][16][17][18][19], and sorting animals based on size and/or behavior [20]. In addition to these applications, nematodes can be sorted in microfluidic devices based on visual markers [5,21].…”