Evidence that the anti-coagulant and lethal properties of a basic phospholipase A2 from snake venom are unrelated

The basic phospholipase A2 (PLA2) from venom of the African elapid Naja nigricollis was previously shown to have anti-coagulant and lethal properties, both of which were abolished by treatment with p-bromophenacyl bromide (pBP). In the present paper we first report that pBP-treated PLA2 is capable of inhibiting the anti-coagulant activity but not the lethal activity of native PLA2, thus suggesting that both properties might be independent. We then confirm this evidence using PLA2-specific monoclonal immunoglobulins. One of these, called HSF, neutralized the lethal activity but not the anti-coagulant activity, whereas another antibody, called HSP2, inhibited the anti-coagulant activity but not the lethal activity of the PLA2. The data presented in this paper are taken as evidence that the anti-coagulant activity is not implicated in the lethal effects of basic PLA2 from Naja nigricollis.