HMGB1 and breast angiosarcoma: Along with the increasing release of HMGB1 in newborn mice infected by RRV, our histopathological findings confirmed progressively increased inflammation and aggregated injury in bile ducts (Fig. 7E), suggesting these matured NK cells attack RRV-infected cholangiocytes persistently and cause damage in bile ducts, which finally leads to development of murine BA (Fig. S8).