Neutralizing monoclonal antibody specific for α‐bungarotoxin: Preparation and characterization of the antibody, and localization of antigenic region of α‐bungarotoxin

Abstract

We prepared an a-bungarotoxin-specific monoclonal antibody that neutralizes the biological activity of the toxin in vivo. The antigenic determinant combining specifically with this antibody was determined on the basis of cross-reaction experiments using three other long neurotoxins and peptide fragments of a-bungarotoxin. The antigenic determinant was located on the peptide fragment containing S34-S35-R36-G37-K38, which forms a part of the expected site that binds to the acetylcholine receptor proteins Monoclonal antibody; Bungarotoxin, a-; Antigenic determinant

Characterization of monoclonal antibodies against Naja naja oxiana neurotoxin I

“…An a-BT/antibody molar ratio of 1: 1.5 resulted in a < 2.5-fold increase for the time to death relative to control animals. A higher amount of NT-I mAb would probably be more efficacious since increased times to death of 4.3-and 13.5-fold were previously reported for an a-BT/mAb molar ratio of 1:1 and 1:5 respectively (Kase et al, 1989). Another study with N. n. atra cobrotoxin and various mAbs also reported prolonged times to death in mice administered toxin plus mAb .…”

“…Previous studies with mAbs against x-BT reported that Ser34-Lys38 and Ser34-Glu4' represent neutralizing epitopes on the central loop (Chuang et al, 1989;Kase et al, 1989). In theory, antibodies which bind to a receptor-binding region of a snake post-synaptic neurotoxin with a higher affinity than the toxin-AchR complex (Kd 1 x I0-9-10-11 M) should have neutralizing potential (Weber and Changeux, 1974).…”

“…Neutralizing epitopes, Ser34-Lys38 (Kase et al, 1989) and Ser34-Glu41 (Chuang et al, 1989), identified by different mAbs against a-BT are located within the central loop which intimately contacts the asubunit of AchR with high affinity (Low, 1979;Love and Stroud, 1986;McDaniel et al, 1987;Ruan et al, 1990). Only one study describes any cross-reactivity, but not neutralization, of other long-chain neurotoxins with anti-(a-BT) mAbs (Kase et al, 1989).…”

“…The immunological properties of N. n. oxiana NT-1 have not been described but extensive monoclonal antibody (mAb) studies have been reported for another long-chain neurotoxin, a-bungarotoxin (a-BT), isolated from Banded Krait (Bungarus multicinctus) venom (Danse et al, 1986;Chuang et al, 1989;Kase et al, 1989;Pachner and Ricalton, 1989). Neutralizing epitopes, Ser34-Lys38 (Kase et al, 1989) and Ser34-Glu41 (Chuang et al, 1989), identified by different mAbs against a-BT are located within the central loop which intimately contacts the asubunit of AchR with high affinity (Low, 1979;Love and Stroud, 1986;McDaniel et al, 1987;Ruan et al, 1990).…”