Type II acute-phase protein (APP) involved in inflammatory responses to trauma. May also play a role in liver development or regeneration. Interacts (via C-terminus) with DNAJC1 (via SANT 2 domain). Levels of ITIH4 in serum increase 3- to 12-fold on inoculation with various bacteria which induce mastitis. Peak levels are reached around 42h-72 h after infection. Appears to be both N- and O-glycosylated. Belongs to the ITIH family.