Selective inhibition of WSN influenza virus haemolysis by pea lectin

The capacity of lectins to inhibit viral haemolysis of chicken erythrocytes was tested, to evaluate the role of carbohydrate in the fusion reaction. Pretreatment of cells with pea lectin provided a 70% to 85% haemolysis inhibition with WSN influenza virus, but only 10% to 14% with PR8 influenza virus. Pea lectin did not detectably bind to virus, nor did it inhibit virus binding to cells, but it did inhibit WSN influenza virus elution. Additionally, pea lectin was active against Sendai virus and B/Lee influenza virus, but inactive against Newcastle disease virus. Haemolysis by WSN and PR8 influenza viruses was unaffected in cells pretreated with concanavalin A, peanut, wheatgerm or soybean lectins. A possible role of cellular carbohydrate in virus-cell fusion is discussed.