Hepatic stellate cell A decreases progressively in liver injury. The activated stellate cell is also responsible for secreting collagen scar tissue, which can lead to cirrhosis. More recent studies have also shown that in vivo activation of hepatic stellate cells by agents causing liver fibrosis can eventually lead to senescence in these cells, marked by increased SA-beta-galactosidase staining, as well as p53 accumulation and activation of Rb–hallmarks of cellular senescence. Senescent hepatic stellate cells have been demonstrated to limit liver fibrosis by activating interactions with NK cells. The cells of Ito were named for Toshio Ito, a twentieth-century Japanese physician, who introduced a
Protocol Relating to the Status of Refugees the temporal and geographic restrictions. This was needed in the historical context of refugee flows resulting from decolonisation. However, the Protocol gave those states which had previously ratified the 1951 Convention and chosen to use the geographically restricted definition the option to retain that restriction. Protocol Relating to the Status of Refugees The Protocol Relating to the Status of Refugees is a key treaty in international refugee law. It entered into force on 4 October 1967, and 146 countries are parties. Where the 1951 United Nations Convention Relating to the Status of Refugees had restricted refugee status to those whose