Skin sensitization of 3, 4-bis (4'-aminofurazano-3') furoxan in mice evaluated by BrdU-ELISA local lymph node assay

Abstract

Objective: To investigate skin sensitization of 3, 4-bis (4'-aminofurazano-3') furoxan (DATF) in mice using 5-bromo-2'-deoxyuridine enzyme-linked immunosorbent assay (BrdU-ELISA) . Methods: A total of 30 specific pathogen-free BALB/C mice were randomly divided into high-, medium-, and low-dose DATF groups, positive control group, and solvent control group, with six mice in each group. The mice in the high-, medium-, and low-dose DATF groups were treated with 50%, 25%, and 10% (0.5, 0.25, and 0.10 g/ml) DATF solution, those in the positive control group were treated with 1% 2, 4-dinitrochlorobenzol (DNCB) , and those in the solvent control group were treated with acetone/olive oil (4∶1) . After treatment, retroauricular lymph nodes were collected and cell suspension was prepared. ELISA was used to measure the level of cell proliferation after the addition of 5-bromo-2'-deoxyuridine (BrdU) , and the BrdU labeling index (LI) and test substance concentration at a stimulation index (SI) of 1.6 (EC1.6) were calculated. Results: There were no significant differences in auricular thickness between groups (P>0.05) , and DAFT did not have skin irritation. Compared with the solvent control group, the high-dose DATF group and the positive control group showed significant increases in the weight of lymph nodes (P<0.05) . Compared with the solvent control group, all the other groups showed significant increases in BrdU LI (P<0.01) . The low-, medium-, and high-dose DATF groups had SIs of 6.1, 8.8, and 12.1, respectively, and the EC1.6 of DATF was 2.2%, which suggested that DATF had strong sensitization. Conclusion: DATF has strong skin sensitization in mice, with reference to the guideline of Organization for Economic Co-operation and Development Item No. 442B (OECD TG 442B) .