Change in location of cytokine-induced neutrophil chemoattractants (CINCs) in pulmonary silicosis

Abstract

Rat cytokine-induced neutrophil chemoattractants (CINCs), which belong to the interleukin-8 family, are known to be induced by treatment with lipopolysaccharide (LPS). Recently, CINCs were grouped into four subtypes—CINC-1, CINC-2α, CINC-2β, and CINC-3—and CINC-1 was considered to be a major isoform among the four CINCs in LPS-induced acute lung inflammation in rats. The purpose of this study was to investigate the change in location of CINCs with chronic inflammation induced by experimental pulmonary silicosis. Administration of silica particles induced lung granulomas. Immunohistochemical staining for CINCs showed that the number of cells positive for CINC-2α, CINC-2β, and CINC-3 was increased, peaking at 1 day after treatment with silica particles, whereas CINC-1 was almost undetectable. We suggest that CINC-2α, CINC-2β, and CINC-3 are the most important chemoattractants in the formation of granulomas in chronic inflammation.