Overview:

Most mammalian cells in the body exist at physiological oxygen levels, often far below the 20–21% oxygen routinely used in standard cell culture. This webinar introduces physoxia, the oxygen environment that more accurately reflects in vivo biology, and explains why oxygen is a critical but often overlooked experimental variable. We will explore how atmospheric oxygen can alter cellular metabolism, stress responses, differentiation, signalilng, and translational relevance. The talk will highlight practical considerations for implementing physoxic workflows and discuss how better oxygen control can improve experimental reproducibility and biological accuracy.

Key Takeways:

-Define physoxia and explain how it differs from atmospheric oxygen culture conditions.
-Describe why oxygen is a critical experimental variable in cell-based research.
-Recognize how non-physiological oxygen levels can affect cellular behaviour and data interpretation.
-Identify practical considerations for implementing physoxic culture workflows.
-Evaluate how physiologically relevant oxygen control can improve reproducibility and translational relevance

Background information

Oxygen is one of the most fundamental regulators of cellular behaviour, yet it is often treated as a constant rather than a controlled experimental variable. In vivo, cells experience tissue-specific oxygen levels that are typically much lower than atmospheric oxygen. For many cell types, standard incubator conditions therefore represent a state of relative hyperoxia rather than normal physiology.

This mismatch can have profound effects on cell function. Culturing cells at atmospheric oxygen may influence oxidative stress, mitochondrial activity, stem cell fate, proliferation, immune responses, gene expression, and disease-related phenotypes. As a result, experimental findings generated under conventional oxygen conditions may not always reflect how cells behave in the body.

Physoxia refers to the use of physiologically relevant oxygen levels in cell culture and experimental design. Rather than applying one universal oxygen concentration, physoxic approaches consider the native oxygen environment of the tissue, organ, developmental stage, or disease context being modelled. This shift supports more biologically meaningful and translationally relevant research.

Adopting physoxia also requires practical changes in laboratory workflows. Oxygen exposure can occur during handling, media changes, imaging, transport, and analysis, not only during incubation. Understanding and managing these variables is essential for researchers who want to improve reproducibility, reduce artefacts, and design experiments that better represent human biology.