The Committee met under the chairmanship of Dr. M.C. Berndt (Australia) with co-chairmen, Dr. G.C. White (USA), Dr. K. Rao (USA), and Dr. H. Deckmyn (Belgium) also attending. Approximately 40 delegates attended the session. The subcommittee presented a final programme primarily covering recent basic and clinical insights into agonist-dependent signal transduction in platelets.
Dr. Koneti Rao spoke on the topic "Disorders of platelet activation" within a context of a proposed classification of congenital disorders of platelet function. He described several patients with abnormalities of platelet aggregation and emphasized the need for a detailed classification for those patients with disorders of platelet secretion and signal transduction. Analysis of these patients, one with low levels of Gaq and the other with defective pleckstrin phosphorylation, have provided important insights into signal transduction pathways induced by ADP and thrombin.
Dr. Michael Barnes described how studies from his laboratory with synthetic collagen sequence peptides have helped clarify the mechanisms by which platelets adhere to collagen and become activated. His studies have indicated that platelets primarily adhere to collagen via the integrin a2b1, but are activated via GPVI. Different sequences in collagen are involved in both these events.
Dr. Steve Watson further developed this theme in an elegant presentation describing research from his laboratory on collagen-dependent signaling pathways. These studies have made collagen-induced platelet activation one of the best understood signaling pathways and illustrated the value of employing multiple approaches in studies of signal transduction.
Dr. Michael Berndt presented a brief overview of genetic abnormalities in Bernard-Soulier syndrome and presented some recent data on structure-function of the GP Ib-IX-V complex using canine-human chimeras. A tabulation of the clinical reports and genotype of all reported Bernard-Soulier syndrome patients was presented as a framework for establishment of a Bernard-Soulier register and web site. There was discussion as to how new information/patients could be added. There was agreement by the subcommittee that the register and web site should proceed and that it would compliment the Glansmann's thrombosthemia register and web site.
The meeting closed with discussion of potential programme topics for the SSC meeting in Washington. There was general agreement that a session on evaluation of GP IIb-IIIa receptor function in the light of oral antagonists would represent an important topic. This and other potential areas for subcommittee evaluation will be further considered in the coming months. There was a general view that earlier announcement of the programme would be valuable for attendees.