Antiviral lectins: Selective inhibitors of viral entry

Abstract

Many natural lectins have been reported to have antiviral activity. As some of these have been put forward as potential development candidates for preventing or treating viral infections, we have set out in this review to survey the literature on antiviral lectins. The review groups lectins by structural class and class of source organism we also detail their carbohydrate specificity and their reported antiviral activities. The review concludes with a brief discussion of several of the pertinent hurdles that heterologous proteins must clear to be useful clinical candidates and cites examples where such studies have been reported for antiviral lectins. Though the clearest path currently being followed is the use of antiviral lectins as anti-HIV microbicides via topical mucosal administration, some investigators have also found systemic efficacy against acute infections following subcutaneous administration.

A Novel High-Mannose Specific Lectin from the Green Alga Halimeda renschii Exhibits a Potent Anti-Influenza Virus Activity through High-Affinity Binding to the Viral Hemagglutinin

“…Monosaccharide residues of Gal, Man, Glc, Fuc, GalNAc, GlcNAc and NeuAc are represented by symbols as shown in the box. Figure 3, HRL40 exclusively bound to some of HM-glycans (11, 12, 14, 15, 17 and 18), and had no binding interaction with other sugar types; complex type N-glycans (1)(2)(3)(4)(5)(6)(7), an N-glycan core pentasaccharide (19), and oligosaccharides from glycolipids (19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29). The binding preference of HRL40 for HM-glycans depended on the structure of branched oligomannosides; the highest binding activity was observed with oligosaccharides 11, 12 and 15 (binding activity, 100%), a little less binding activity with oligosaccharides 14 (89%) and 17 (74%), and moderate activity was with an -7), high-mannose type N-glycans (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18), an N-glycan core pentasaccharide (19), and oligosaccharides originated from glycolipid (20)(21)(22)(23)(24)(25)(26)(27)(28)(29).…”

“…The oligosaccharide-binding property of HRL40 was examined by a centrifugal ultrafiltration-HPLC method [6,28] with a serial of pyridylaminated (PA-) oligosaccharides, including complex type N-glycans (1-7 in Figures 2 and 3), HM-glycans (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18), an N-glycan core pentasaccharide (19), and oligosaccharides originated from glycolipids (20)(21)(22)(23)(24)(25)(26)(27)(28)(29). The schematic structures of oligosaccharides examined are shown in Figure 2.…”

Better influenza vaccines: an industry perspective

“…Six consensus sequences from influenza NP, M1 and matrix 2 (M2) proteins were identified and synthesized into a candidate vaccine. Flu-v has been shown to induce a specific CD8 + response against these conserved epitopes and confer protection against heterotypic infection in mice [59], and a Phase Ib challenge trial also showed that the blood cells from immunized subjects exhibited cross reactive immunity against different influenza viruses [62,63].…”

In vitro antiviral activity of BanLec against herpes simplex viruses type 1 and 2

“…Lectins are a unique and heterologous class of proteins with the ability to recognize and reversibly bind a variety of sugar structures present on the cell surface (Santos et al, 2014). They are found in a wide range of organisms, from viruses and bacteria to animals, plants, and humans (Mitchell et al, 2017). They have important biological functions in the organisms, including cell-cell interaction, protection from pathogens, cell adhesion, and intracellular translocation of glycoproteins, and they also act as storage proteins (Yamashita et al, 1999;Jiang et al, 2006;Wang et al, 2007).…”