[Experimental research on anti-respiratory syncytial virus effect in vitro of earthworm coelomic fluid].

Objective: To explore the antivirus function in vitro of earthworm coelomic fluid (ECF) by researching its effect on inhibiting respiratory syncytial virus (RSV).

Methods: By the method of Hep-2 cell culture and using ribavirin as a positive control, the anti-RSV effect of ECF was investigated by observing cytopathic effect (CPE) with MTT colorimetric assay.

Results: In Hep-2 cells, the CC50 of ECF and ribavirin were 3.11 mg/ml and 1.35 mg/ml separately. In the experiment of ECF directly killing RSV, the IC50 of ECF was 184.1 microg/ml, SI was 16.87; In the experiment of ECF preventing RSV invasion, no antiviral function of ECF within the experimental concentration range was observed; In the experiment of ECF inhibiting RSV replication, the IC50 of ECF was 1555. 8 microg/ml, SI was 1.99.

Conclusion: ECF couldn't prevent virus from invading into host cell, but showed direct killing-virus function and inhibition of the virus replication.