Part II: Granulocyte-Colony Stimulating Factor Adjunct Therapy for Biliary Atresia

This is a prospective, randomized, multi-institutional trial in KBA and NoK subjects to be conducted under a Food and Drug Administration approved Investigational New Drug application. The KBA group is composed of just operated Kasai patients with intraoperative liver biopsy-confirmed BA. Their clinical characteristics have been described in the previously completed Phase 1 study under CR00005169 (ie. inclusion and exclusion criteria as described below) The NoK group will be composed of newly diagnosed BA patients, including the following: * surgical patients in whom the Kasai was not performed for intraoperative technical reasons or due to advanced liver disease, who also have no option for rescue liver transplantation. * Unoperated patients whose family refuses surgery or who are not operative candidates Having met the same inclusion and exclusion criteria as the Kasai KBS group, * eligible KBA subjects will be randomized to GCSF vs. no-GCSF at the 10 ug/kg/d dose to be given subcutaneously for 3 consecutive daily doses on the third day following the Kasai procedure. * eligible NoK subjects will be randomized to GCSF vs. no-GCSF at the 10 ug/kg/d dose to be given subcutaneously for 3 consecutive daily doses on the third day following diagnostic liver biopsy.