Pilot 28 – Manicone

P30 CFRTC – Pilot 28

Identifying Novel Compounds to Polarize Macrophages toward Reparative States

PI: Anne Manicone, MD
Associate Professor, Medicine, Pulmonary and Critical Care
P30 CFRTC Publication

Funding Period: 2024 – 2025

Abstract: Cystic Fibrosis is a genetic disorder due to variants of the cystic fibrosis transmembrane conductance regulator (CFTR) gene and adversely affects function of the lungs, pancreas, intestines, and hepatobiliary tree. There are numerous studies highlighting the presence of chronic intestinal inflammation in CF. Intestinal inflammation may exacerbate malabsorption and nutritional status in CF, and studies suggest that gut health can impact pulmonary function. Macrophages are key orchestrators of inflammation and repair processes in the intestine, and studies implicate a pro-inflammatory macrophage phenotype in CF that may contribute to excessive tissue inflammation and injury. Macrophages can be targeted to change their activation state so that they downregulate pro-inflammatory cytokines/chemokines, up-regulate anti-inflammatory ones, clear inflammatory debris and apoptotic cells, and promote epithelial cell proliferation. One such pathway that drives these reparative macrophage phenotypes includes IL-4/STAT6 signaling. Over-expression of IL-4 or adoptive transfer of IL-4 stimulated macrophages attenuates TNBS-induced colitis, whereas deficiency of the IL-4 receptor alpha chain triggers early onset severe colitis in mice. These findings suggest a beneficial role for IL4/STAT6 pathway activation in macrophages to dampen intestinal inflammation. Based on these findings, we hypothesize that identification of compounds that promote IL4/STAT6 polarization may be used as therapeutics in dampening CF-related intestinal inflammation.

In aim 1, we will use high throughput studies to identify novel compounds that promote or enhance IL-4/STAT6 polarization. We will generate macrophage reporter cell lines to identify reparative and pro-inflammatory polarized states. These cells will be used to screen 50,000 entity Diversity Set (Chembridge), which covers all biological spaces thought to interact with small molecules. Select hits will undergo screening for cell toxicity, dose-responses, and validation in primary human and murine macrophages.

In aim 2, we will test novel compounds that promote IL-4/STAT6 polarization for toxicity and therapeutic efficacy in mice. Lead candidates will undergo therapeutic testing in a murine CF model. This proposal will use innovative approaches and concepts to identify compounds that promote reparative macrophage phenotypes as novel immune-modulating therapeutics.