PGS, this is the best I can do w/o more research. Perhaps the papers of Dr. Thorpe will have more of the information you're seeking, if you're sufficiently interested:
I don't think these references answer PGS' question. From my initial reading on the subject PS expression is a normal component of the apoptotic mechanism, part of which is maintenance of immune tolerance. In and of itself antibody binding would seem to restore the status quo. By the co's explanation if Bavi is somehow abrogating that balance then I would think there should be incidences of autoimunne sequalae. From the ASCO poster this appears to be absent in the AE profile as is data on immune activation. I don't yet see the alignment of proposed MOA to clinical outcomes data that would give a better level of confidence that the observed results are real.