Antiviral Activities of Heparan Sulfate Mimetic RAFT Polymers Against Mosquito-borne Viruses

Mosquito-borne viruses are a major worldwide health problem associated with high morbidity and mortality rates and significant impacts on national healthcare budgets. The development of antiviral drugs for both the treatment and prophylaxis of these diseases is thus of considerable importance. To address the need for therapeutics with antiviral activity, a library of heparan sulfate mimetic polymers was screened against dengue virus (DENV), Yellow fever virus (YFV), Zika virus (ZIKV), and Ross River virus (RRV). The polymers were prepared by RAFT polymerization of various acidic monomers with a target MW of 20 kDa (average M_n ∼ 27 kDa by GPC). Among the polymers, poly(SS), a homopolymer of sodium styrenesulfonate, was identified as a broad spectrum antiviral with activity against all the tested viruses and particularly potent inhibition of YFV (IC₅₀ = 310 pM). Our results further uncovered that poly(SS) exhibited a robust inhibition of ZIKV infection in both mosquito and human cell lines, which points out the potential functions of poly(SS) in preventing mosquito-borne viruses associated diseases by blocking viral transmission in their mosquito vectors and mitigating viral infection in patients.