DIFFERENTIAL CHANGES IN THE CONCENTRATIONS OF CYTOKINE-INDUCED NEUTROPHIL CHEMOATTRACTANT (CINC)-1 AND CINC-2 IN EXUDATE DURING RAT LIPOPOLYSACCHARIDE-INDUCED INFLAMMATION

Recently we have purified four neutrophil chemotactic factors from con ditioned medium of rat granulation tissue, Two chemokines besides cyto kine-induced neutrophil chemoattractant-1 (CINC-1, formerly called CIN C) and CINC3/macrophage inflammatory protein-2 (MIP-2) were novel chem oattractants, designated as CINC-2 alpha and CINC-2 beta. In the prese nt report, we developed an enzyme-linked immunosorbent assay (ELISA) s pecific for CINC-2 The biotin-streptavidin sandwich ELISA for CINC-2 b eta detected CINC-2 alpha and CINC-2 beta equally well between 1 ng/ml and 300 ng/ml, but did not show cross-reactivity with CINC-1 and CINC -3. The concentrations of CINC-1 and CINC-2 in the exudate during rat lipopolysaccharide (LPS)-induced inflammation were determined. The CIN C-1 concentration in the exudate reached a maximum at 4 h after LPS in jection, whereas the CINC-2 level steadily increased up to 8 h. The nu mber of infiltrated cells in the exudate increased linearly until 6 h and gradually up to 8 h. Increase in the cell number was correlated wi th total concentrations of CINC-1 and CINC-2. The results suggest that CINC-2 as well as CINC-1 plays an important role in accumulation of n eutrophils into the inflammatory lesion of LPS-induced inflammation in rats. (C) 1996 Academic Press Limited