“…The purification scheme for isolation of the lipoprotein inhibitor was devised by utilizing typical biochemical fractionation procedures and noting the improvement in HAI activity on a protein basis. Bicarbonate solutions are often used in the initial stages of cell membrane preparation (4,23,26,34). Laucikova (20,21) used bicarbonate extraction and isoelectric precipitation at pH 5.1 to separate an inhibitor of influenza virus HA from chick embryo chorioallantoic membrane extracts.…”