Immune and epithelial responses to textile dyes: the role of chemical structure in toxicity.

Continuous exposure to textile dyes can result in potential health risks, such as inflammatory and allergic responses. We investigated immunotoxicity, and epithelial responses induced by Disperse Blue 1, 124, 79.1, and 183 when in co-culture with swine peripheral blood mononuclear cells (PBMCs), intestinal porcine epithelial cells (IPEC), and human epidermal skin scaffolds. PBMC cytokine production (IFN-γ and TNF-α), cell viability, IPEC gene expression profiles (by Nanostring analysis) and histopathology of human epidermis were evaluated. Disperse Blue 124 strongly increased pro-inflammatory cytokines without significant cytotoxicity, suggesting high sensitization potential. Contrarily, Disperse Blue 1 exhibited high cytotoxicity despite moderate cytokine production. Nanostring analysis revealed prominent epithelial inflammation (CCL20 upregulation) and compromised barrier integrity (CLDN-4) with Blue 1 and Blue 124, but not Blue 79.1 and 183. Histopathology further confirmed epidermal damage, with Blue 1 and 124. Therefore, dye-induced effects correlated with chemical structure, molecular weight, hydrophobicity, and functional groups, supporting the hypothesis that structural properties influence toxicity and absorption.