Tailored oxygen in cell cultures: an innovative system for studying tumors and new drugs

In human tissues, oxygen is not distributed uniformly: it is present in varying concentrations, forming complex gradients that profoundly influence cell behavior — particularly that of tumor cells. Replicating this complexity in the laboratory has always been one of the most challenging problems in biomedical research. Now, a group of researchers at the University of Bologna has found an elegant and accessible way to do it.

The system — presented in an article published in Device, a Cell Press journal — is based on an "active" biomaterial (a hydrogel composed of proteins and enzymes) that is patterned using microfabrication and digital printing techniques onto the bottom of standard cell culture plates. Once in place, the material consumes oxygen in a controlled manner, generating three-dimensional gradients that mimic those found in living tissues.

"In traditional cell cultures, oxygen distribution is uniform — but that is not the case in the human body," explains Stefania Rapino, Professor at the Department of Chemistry "Giacomo Ciamician" at the University of Bologna, who coordinated the study. "Cells actually experience very different oxygen levels depending on their position. Our goal was to recreate this complexity in a simple and accessible way."

Unlike more complex approaches — such as the production of organoids or the use of organ-on-chip technologies — the new device does not require complex equipment such as hypoxic incubators or advanced microfluidic systems. On the contrary, it can be easily integrated into existing laboratory workflows, while still offering a high degree of control over the cellular environment.
Experimental results confirm its effectiveness. Tested on breast tumor cell cultures, the device successfully reproduced cellular responses to oxygen gradients closely resembling those observed in real tissues.

"The tests we carried out on tumor cells show adaptations typical of hypoxic conditions, such as reduced growth in oxygen-depleted areas and the activation of specific molecular survival mechanisms," confirms Rapino. "This is a particularly significant result, because hypoxia is a key feature of many tumors and is associated with disease progression and therapy resistance".

Another strength of the new system is its versatility: it allows cells to be observed and analyzed using standard laboratory techniques, allowing easy retrieval for subsequent molecular studies. It can therefore be used both for basic research and for more advanced applications such as drug screening.

The technology has already led to industrial applications: it is protected by two patents held by the University of Bologna and has given rise to the academic spin-off InSimili, founded to translate this innovation into practical applications in biomedical and industrial settings.

The study was published in Device (Cell Press) under the title "Microfabrication of cell culture microenvironments with spatially controlled oxygen levels". Contributors from the University of Bologna include Maila Becconi, Marco Malferrari, Daniela Salvatore, Francesco Zerbetto, and Stefania Rapino (Department of Chemistry "Giacomo Ciamician"), Andreas Lesch (Department of Industrial Chemistry "Toso Montanari"), Isabella Zironi (Department of Physics and Astronomy "Augusto Righi"), and Maria Conte, Stefano Salvioli, and Gastone Castellani (Department of Medical and Surgical Sciences).