ELVIS imaging system studies cells in orbit

23 Apr 2025

Portland State University and JPL platform tests ability of microorganisms to thrive in space.

The Extant Life Volumetric Imaging System, or ELVIS, is about to test the resilience of cells and microbes in orbital environments.

Developed by Portland State University (PSU) and JPL, ELVIS is a multi-microscope platform intended to allow the imaging of large sample volumes at high resolution via fluorescent labeling.

This should offer scientists a closer look at the intricate structure, volume, and environmental interactions of cellular organisms, biological assessments that could shed light on the ability of life to thrive in the extreme environments of space.

The device was onboard CRS-32, SpaceX's 32nd commercial resupply services mission to the orbiting International Space Station.

ELVIS combines expertise in biology, physics, and cutting-edge imaging technology, commented PSU's Jay Nadeau, a principal investigator on the project.

"We are thrilled to leverage the ISS National Lab to prepare ELVIS for its future roles in space exploration missions," said Nadeau. "The successful operation of ELVIS in the demanding conditions of space not only paves the way for its use in off-Earth environments but also holds implications for enhancing biomedical and microbiological research on our planet."

Development of ELVIS began in 2022, as an investigation into microscope systems suitable for ultimate use on or around other moons and planets, where both sample concentrations and the size of potential organisms may be extremely small.

With one eye on an eventual lander for Jupiter's moon Europa, the project's design combined digital holographic microscopy (DHM), in which returned light from an object is recorded as a hologram, and volume fluorescence imaging (VFI). The team envisaged a complete fluid motion, staining and image acquisition sequence being carried out autonomously.

Observing microgravity in action

In the final ELVIS platform delivered to orbit, the DHM module "provides better than 0.8-micron spatial resolution across a 0.25 mm³ flow-through cell, and has the ability to detect fewer than 100 cell-like particles in a 1 mL volume," according to PSU data.

Sample volumes viewed by the interferometric approach of DHM are typically two to three orders of magnitude greater than conventional microscopy with the same elements, noted PSU, improving the throughput of the system. Machine-learning algorithms are used to extract particle tracks and identify lifelike movement of single-cell organisms.

The same sample volume is simultaneously imaged at a lower resolution by ELVIS's lightfield VFI, to spatially correlate the fluorescent detection of proteins, cell walls, and nucleic acids for further identification of potential biological material.

"While the DHM captures high-resolution images with high-sensitivity for the sample's morphology and motility, the VFI looks for chemical/fluorescence biosignatures that are missed by DHM," said the ELVIS team.

Once up and running on the ISS, ELVIS will observe two resilient types of Earth-based life forms: Euglena gracilis microalga and Colwellia psychrerythraea, a bacterium that thrives in frigid ocean waters. The goal is to test their observable and genetic adaptations to microgravity.

The insights gained could illuminate how life might survive beneath the icy shells of distant moons like Europa and Enceladus, significantly enhancing the search for life outside Earth.