# Immune profiling of mouse lung adenocarcinoma paraffin tissues using multiplex immunofluorescence panel: a pilot study

## TL;DR

This study uses a multiplex immunofluorescence panel to profile immune cells in mouse lung cancer tissues, revealing spatial patterns of immune cell distribution and PD-L1 expression.

## Contribution

The study introduces an optimized eight-color immunofluorescence panel for immune profiling in mouse lung adenocarcinoma paraffin tissues.

## Key findings

- The mIF panel successfully identified immune cell expression patterns in mouse lung cancer tissues.
- T cells and macrophages expressing PD-L1 were found near malignant cells.
- Sparse immune cell infiltration was observed in the studied cohort.

## Abstract

Immune profiling has become an important tool for identifying predictive, prognostic and response biomarkers for immune checkpoint inhibitors from tumor microenvironment (TME). We aimed to build a multiplex immunofluorescence (mIF) panel to apply to formalin-fixed and paraffin-embedded tissues in mice tumors and to explore the programmed cell death protein 1/ programmed cell death 1 ligand 1 (PD-1/PD-L1) axis.

An automated eight-color mIF panel was evaluated to study the TME using seven antibodies, including cytokeratin 19, CD3e, CD8a, CD4, PD-1, PD-L1, F4-80 and DAPI, then was applied in six mice lung adenocarcinoma samples. Cell phenotypes were quantified by software to explore the co-localization and spatial distribution between immune cells within the TME. This mice panel was successfully optimized and applied to a small cohort of mice lung adenocarcinoma cases. Image analysis showed a sparse degree of immune cell expression pattern in this cohort. From the spatial analysis we found that T cells and macrophages expressing PD-L1 were close to the malignant cells and other immune cells.

Comprehensive immune profiling using mIF in translational studies improves our ability to correlate the PD-1/PD-L1 axis and spatial distribution of lymphocytes and macrophages in mouse lung cancer cells to provide new cues for immunotherapy, that can be translated to human tumors for cancer intervention.

The online version contains supplementary material available at 10.1186/s42826-024-00210-w.