ABSTRACT Although immune checkpoint inhibitor (ICI) therapy has been a tremendous clinical success, just ~20% of non- small cell lung cancer (NSCLC) patients respond to anti-PD1/PDL1 therapy. The two major factors predictive of favorable treatment response to ICI therapy are the presence of the IFNG signature and evidence of CD8+ T cell infiltration into malignant tumor. Work from our group has shown that neutrophil infiltrated non-small cell lung cancers do not display the IFNG signature, do not display CD8+ infiltration into malignant tumor, and do not respond to ICI treatment. Our hypothesis to explain these observations is that tumor-associated neutrophils release proteinases that degrade key cytokines (IFNG), chemokines (CXCL-9, -10, -11) and a chemokine receptor (CXCR3) that destroys the IFNG mediated chemotactic gradient that facilitates T cell infiltration into tumors. The proposed studies will demonstrate that a number of key neutrophil-derived proteinases are capable of degrading T cell recruiting chemokines and CXCR3 and identify the novel cleavage products resulting from these events. The functional consequences of these proteolytic events will be demonstrated in novel multicellular tumor-in-chip systems and in state-of-the art mouse models of lung cancer. Lastly, we will employ a combined fluorescent in-situ hybridization (FISH) and multiplexed immunohistochemistry (M-IHC) panel to study the relationship between CXCL9 expressing tumor cells, infiltrating CD8+CXCR3+ T cells, and TAN and determine the impact that these measures have on ICI treatment outcomes in NSCLC patients.