Electrotransjection of pp60v-src monoclonal antibody inhibits activation of XXXX in platelets. A new mechanism for platelet-activating factor responses.

@entity19260 @entity10393 @entity95 @entity3353 @entity71384
Antibodies to pp60v-arc and @entity10393 were introduced into @entity95 platelets using an electropermeabilization technique. The presence of these antibodies inside platelets was detected by flow cytometry. Platelet-activating factor (PAF)-stimulated @entity3353 activity ( @entity19260 production) and aggregation were dramatically inhibited in platelets transjected with either of these antibodies. Incubation of these antibodies with intact cells (i.e. nonpermeabilized) or electrotransjection of several nonspecific antibodies/agents (e.g. goat anti-mouse IgG, mouse serum, human platelet glycoprotein Ib monoclonal antibody, and fetal calf serum) into platelets had no effect on the PAF responses. trpE (another isotype-matched control antibody of pp60v-src) and pp56lck polyclonal antibody (another src-related kinase not present in platelets) also had no effect on PAF-induced aggregation and @entity19260 production in permeabilized platelets. This indicates that the effect of internalized pp60v-src antibody is direct and specific in platelets. Stimulation of platelets by PAF increased the association and phosphorylation of both pp60c-src (60 kDa) and @entity71384 (145 kDa). This study provides the first evidence in platelets for a direct and specific involvement of pp60c-src in PAF-mediated @entity3353 activation and aggregation response.
