A microfluidic platform for automated phenotyping during full lifespan of Caenorhabditis elegans at high-throughput

We present a multiplexed and automated microfluidic platform for phenotyping of C. elegans during their full lifespan and at high-throughput. We used the fluorescent hsp-6::gfp strain of worms and performed experiments to observe the effect of four different E. coli concentrations supplied for growth. We cultured worms in microfluidic chambers during their lifespan and quantified their motility. Nematodes were also confined at various time points inside tapered constriction channels for imaging to observe the mitochondrial stress, as expressed by fluorescence, and to measure their growth parameters as function of the amount of applied food.

A design of experiment approach for efficient multi-parametric drug testing using a Caenorhabditis elegans model

Matteo Cornaglia, Martinus Gijs, Maria Cristina Letizia, Giuseppe Tranchida, Raphaël Etienne Jean Trouillon

When studying the drug effectiveness towards a target model, one should distinguish the effects of the drug itself and of all the other factors that could influence the screening outcome. This comprehensive knowledge is crucial, especially when model organisms are used to study the drug effect at a systemic level, as a higher number of factors can influence the drug-testing outcome. Covering the entire experimental domain and studying the effect of the simultaneous change in several factors would require numerous experiments, which are costly and time-consuming. Therefore, a design of experiment (DoE) approach in drug-testing is emerging as a robust and efficient method to reduce the use of resources, while maximizing the knowledge of the process. Here, we used a 3-factor-Doehlert DoE to characterize the concentration-dependent effect of the drug doxycycline on the development duration of the nematode Caenorhabditis elegans. To cover the experimental space, 13 experiments were designed and performed, where different doxycycline concentrations were tested, while also varying the temperature and the food amount, which are known to influence the duration of C. elegans development. A microfluidic platform was designed to isolate and culture C. elegans larvae, while testing the doxycycline effect with full control of temperature and feeding over the entire development. Our approach allowed predicting the doxycycline effect on C. elegans development in the complete drug concentration/temperature/feeding experimental space, maximizing the understanding of the effect of this antibiotic on the C. elegans development and paving the way towards a standardized and optimized drug-testing process.

2018

Automated phenotyping of Caenorhabditis elegans embryos with a high-throughput-screening microfluidic platform

Tunç Alkanat, Hüseyin Baris Atakan, Matteo Cornaglia, Martinus Gijs, Raphaël Etienne Jean Trouillon

The nematode Caenorhabditis elegans has been extensively used as a model multicellular organism to study the influence of osmotic stress conditions and the toxicity of chemical compounds on developmental and motility-associated phenotypes. However, the several-day culture of nematodes needed for such studies has caused researchers to explore alternatives. In particular, C. elegans embryos, due to their shorter developmental time and immobile nature, could be exploited for this purpose, although usually their harvesting and handling is tedious. Here, we present a multiplexed, high-throughput and automated embryo phenotyping microfluidic approach to observe C. elegans embryogenesis after the application of different chemical compounds. After performing experiments with up to 800 embryos per chip and up to 12h of time-lapsed imaging per embryo, the individual phenotypic developmental data were collected and analyzed through machine learning and image processing approaches. Our proof-of-concept platform indicates developmental lag and the induction of mitochondrial stress in embryos exposed to high doses (200mM) of glucose and NaCl, while small doses of sucrose and glucose were shown to accelerate development. Overall, our new technique has potential for use in large-scale developmental biology studies and opens new avenues for very rapid high-throughput and high-content screening using C. elegans embryos. Microfluidics: High-throughput screening of embryosA new microfluidic approach enables the high-throughput and automated phenotyping of C. elegans embryos. Understanding the effect of osmotic stress-induced damage on cells is vital for understanding a number of biological processes. C. elegans embryos are considered ideal model systems for osmotic studies, but their phenotyping is traditionally a labor intensive and time-consuming process. Now, a team from EPFL in Switzerland led by Martin Gijs demonstrate a microfluidic platform for high-throughput phenotyping of C. elegans. Embryos are exposed to various osmotic compounds, followed by an automated phenotyping script to assess phenotypes via machine learning and image processing. Their proof of concept experiment demonstrates that their technique can be used for a systems-based approach for osmotic studies.

2020

Automated phenotyping of Caenorhabditis elegans embryos with a high-throughput-screening microfluidic platform

Tunç Alkanat, Hüseyin Baris Atakan, Matteo Cornaglia, Martinus Gijs, Raphaël Etienne Jean Trouillon

2020