Publication Date
1-1-2024
Journal
Frontiers in Medicine
DOI
10.3389/fmed.2024.1362336
PMID
38560382
PMCID
PMC10978656
PubMedCentral® Posted Date
3-15-2024
PubMedCentral® Full Text Version
Post-print
Published Open-Access
yes
Keywords
dry eye, macrophage, cornea nerve, innate inflammation, CXCL1
Abstract
BACKGROUND: Dry eye causes corneal inflammation, epitheliopathy and sensorineural changes. This study evaluates the hypothesis that dry eye alters the percentages and transcriptional profiles of immune cell populations in the cornea.
METHODS: Desiccating stress (DS) induced dry eye was created by pharmacologic suppression of tear secretion and exposure to drafty low humidity environment. Expression profiling of corneal immune cells was performed by single-cell RNA sequencing (scRNA-seq). Cell differentiation trajectories and cell fate were modeled through RNA velocity analysis. Confocal microscopy was used to immunodetect corneal immune cells. Irritation response to topical neurostimulants was assessed.
RESULTS: Twelve corneal immune cell populations based on their transcriptional profiles were identified at baseline and consist of monocytes, resident (rMP) and MMP12/13 high macrophages, dendritic cells (cDC2), neutrophils, mast cells, pre T/B cells, and innate (γDT, ILC2, NK) and conventional T and B lymphocytes. T cells and resident macrophages (rMP) were the largest populations in the normal cornea comprising 18.6 and 18.2 percent, respectively. rMP increased to 55.2% of cells after 5 days of DS. Significant changes in expression of 1,365 genes (adj
CONCLUSION: These findings indicate that DS recruits monocytes that differentiate to macrophages with increased expression of inflammation associated genes. The proximity of these macrophages to cornea nerves and their expression of neurosensitizers suggests they contribute to the corneal sensorineural changes in dry eye.