In vitro study on the neutralizing LPS activity of modeling peptides from the limulus antilipopolysaccharide factor

Objective To evaluate the endotoxin-neutralizing activity of modeling peptides from the limulus antilipopolysaccharide factor (MPLALFs, Ms) in vitro. Methods The endotoxin-binding activity of Ms was examined by biosensor technique and shown in values of Kon and Kd. The endotoxin-neutralizing effect was analyzed by limulus amebocyte lysate test. Results The biosensor technique results showed that the Kon values of M_0, M_1, M_2, M_3, M_4, M_6, M_8 and M_ 10 binding to LPS 055∶B5 were (840±5.716), (549±6.532), (842±6.530), (627±2.450), (996±5.716), (814±8.982), (556±1.633) and (635±2.449) arc second, of which M_4 and M_1 had the highest and lowest endotoxin-binding activity, respectively. The M_4 reacted to LPS with a Kd of 72.377 μmol/L. The results obtained by the limulus amebocyte lysate test were the same with those from the biosensor technique. Conclusion M_4 has a potential good endotoxin-neutralizing effect in vitro.