Lectins as Promising Therapeutics for the Prevention and Treatment of HIV and Other Potential Coinfections

Mazalovska, Milena; Kouokam, J. Calvin

BanLec is a member of the family of the jacalinrelated lectins. The lectin isolated from the fruit of bananas, Musa acuminate, also has affinity towards high-mannose structures. The native lectin is a dimer composed of two identical subunits of 15 kDa containing 141 amino acids [27] and two sugar binding sites each [43] . It was shown that BanLec can inhibit various HIV-1 isolates with different tropisms in vitro, with IC50 values in the low nanomolar range. Similar to the above carbohydrate-binding proteins, BanLec inhibits HIV infection at the viral entry step by binding to high-mannose structures present on the heavily glycosylated gp120 in a concentration dependent manner, thus preventing attachment of the virus to the cell. Swanson et al. also reported that BanLec is a potent mitogen for murine T-cells, although the effects depend on the mouse strain used. Interestingly, a mutation within the sugar-binding site of BanLec notably reduces its mitogenic activity without affecting HIV neutralization. The new engineered lectin has the potential to be used as a microbicide drug [44] .