Poster Presentation: Shruthi Bare

ABSTRACT

Paracorporeal tissue-on-chip device model for real-time, cellular-resolution probing of tumor immune responses

Shruthi Bare¹, Lauren Castle¹, Linzheng Shi¹, Byungjun Kang¹, Mckenzie Garcia², William Polacheck², Hadi T. Nia¹

¹Department of Biomedical Engineering, Boston University; ²Department of Biomedical Engineering, UNC Chapel Hill

Objective: Tumor-on-chip technologies have advanced rapidly, due to their ability to continuously image disease progression. However, a key limitation of existing models is the absence of an integrated immune response. To address this gap, we are developing a “paracorporeal” tissue-on-chip platform that connects a microengineered tumor construct directly to the murine circulatory system. This approach allows whole blood from an awake and free moving mouse to perfuse over tumor cell islands enabling the imaging of a real time immune-response in a physiologically relevant tumor microenvironment. Here, we demonstrate the tissue-on-chip architecture developed for the platform. This platform can be used to quantify the differences in immune response dynamics between aged and young mice.

Materials/Methods: PDMS-coated coverslips were functionalized using dopamine hydrochloride and poly-L-lysine in a PDMS mask to create cell-adherent islands. The coverslips were then covered and incubated with pluronic F127 to prevent cell adhesion on the remaining surfaces. Melanoma cells (Yummer-GFP) were then seeded onto the chip and incubated overnight. A 3D printed negative mold was used to make a PDMS-based flow chamber. The chip was assembled by clamping the PDMS piece to the cell-patterned coverslip using acrylic pieces. Mice were prepared using Arteriovenous microsurgery connecting the carotid artery and jugular veins to catheters that are exteriorized in the mouse. After recovery, the mice were connected to the chip where fluorescently labelled circulating immune cells and patterned cancer cells are imaged using confocal microscopy.

Results/Conclusions: We were able to successfully pattern islands of cancer cells onto slides. We achieved leak-free continuous flow over the islands while maintaining single-cell resolution of the cancer cells. This novel approach enables us to study continuous, high temporal resolution immune response to cancer cells in a physiologically relevant environment. Ongoing work involves the quantification of the effect of aging on the dynamics of tumor immune response.