Antiviral Activity of low-MW Dextran Sulphate (Derived from dextran MW 1000) Compared to Dextran Sulphate Samples of Higher MW

Dextran sulphate inhibits the replication of enveloped viruses (such as retro-, herpes-, toga, arena-, rhabdo-, orthomyxo- and paramyxoviruses), but is inactive against non-enveloped viruses (such as polio, Coxsackie and reovirus). Within the molecular weight (MW) range of 10000–50000, not much variation was observed in the antiviral potencies of different dextran sulphate (DS) samples, irrespective of the virus examined. However, in contrast with the higher MW samples, the low MW DS sample (prepared from dextran with a MW of 1000) was virtually inactive against herpes simplex virus type 1 and type 2, vesicular stomatitis virus, vaccinia virus, influenza A virus, respiratory syncytial virus and togaviruses (Sindbis, Semliki Forest). It was 10–20-fold less active than the higher MW samples against cytomegalovirus and arenaviruses (Junin, Tacaribe). The inhibitory potency of the 1000 MW DS sample against human immunodeficiency virus (HIV) varied considerably depending on the virus strain and cell type. When examined in MT-4 cells, the 1000 MW DS sample was 7000-, 1000-, 200- or 10-fold more inhibitory to HIV-1_HE than HIV-2_EHO, HTLV-III_B, HTLV-III_RF and LAV-2_ROD, respectively. In CEM cells, however, HIV-1_HE was less sensitive to the inhibitory effect of the 1000 MW DS sample than HIV-2_EHO, equally sensitive as HTLV-III_B and fivefold more sensitive than LAV-2_ROD.