Production of Human Pancreatitis-Associated Protein (hPAP) in Komagataella phaffii (Pichia pastoris)

Abstract

Pancreatitis-associated protein (PAP) is a pancreatic stress protein that is not produced in a healthy pancreas but is highly synthesized in pancreatic acinar cells in response to acute and chronic pancreatitis, hypoxia, toxins, diabetes, lipopolysaccharides hypotransferrinemia and organ transplantation. Changes in the PAP levels in serum are an important biological marker in the early stage of pancreatic diseases. In this study, the recombinant human PAP protein, which has the potential to be used as a diagnostic marker and as research material in proliferation, apoptosis, cell migration, cell invasion, and immunoassay studies, was expressed efficiently under the control of the AOX1 gene promoter in the Komagataella phaffii (Pichia pastoris) (K. phaffii) X33 strain. We describe the conditions required for the efficient production of PAP protein by methanol induction and its use without purification. The produced unpurified protein was tested in sandwich ELISA and showed consistent results with the commercial product. These results are encouraging that the protein produced can be used as a biomarker standard in ELISA tests without the cost and labor of purification.