A 3D tumor spheroid model with robust T cell infiltration for evaluating immune cell engagers.

A strong interest in drugs targeting the tumor microenvironment (TME) necessitates new experimental systems that incorporate key TME components. Compared to traditional 2D cell lines, 3D spheroids from patient-derived xenograft (PDX) materials may better capture patient tumor characteristics. We developed and validated a 3D tumor spheroid model from non-small cell lung cancer (NSCLC) PDXs to enable T cell infiltration. Histologic and transcriptomic analysis suggested that tumor spheroids closely recapitulate the source PDX tumor tissues. Consistent T cell infiltration into tumor spheroids was achieved using a well-established magnetic nanoparticle technology, which maintained T cell function and tumor-killing activity. Drug treatment studies with immunotherapy agents also demonstrated the potential scalability of 3D tumor-T cell spheroids in assessing drug activity, including tumor viability and cytokine secretion. This platform provides a useful tool for evaluating drug candidates that can be translated to patient tumor responses related to both tumor intrinsic and TME factors.