The depolymerized fucosylated chondroitin sulfate from sea cucumber potently inhibits HIV replication via interfering with virus entry.

Fucosylated chondroitin sulfate (FuCS-1) is a nontoxic and water-soluble depolymerized glycosaminoglycan obtained from the sea cucumber Thelenota ananas. Anti-HIV activities of FuCS-1 were evaluated in the present study. FuCS-1 was effective in blocking laboratory strain HIV-1IIIB entry and replication (4.26μg/mL and 0.73μg/mL, respectively), and inhibiting infection by clinic isolate HIV-1KM018 and HIV-1TC-2 (23.75μg/mL and 31.86μg/mL, respectively) as well as suppressing HIV-1 drug-resistant virus. It also inhibited HIV-2ROD and HIV-2CBL-20 replication (100μg/mL). Notably, FuCS-1 showed highly effective antiviral activity against T-20-resistant strains (EC50 values ranging from 0.76μg/mL to 1.13μg/mL). Further studies indicated that FuCS-1 can potently bind the recombinant HIV-1 gp120 protein, but no inhibition of recombinant HIV-1 reverse transcriptase was observed. In conclusion, FuCS-1 inhibited several strains of HIV-1 replication with different potencies. These results suggest that FuCS-1 may possess great potential to be further developed as novel HIV-1 entry inhibitor for treatment of HIV/AIDS patients, particularly for those infected by T-20-resistant variants.