Intestinal proteome changes during infant necrotizing enterocolitis.

Background: Changes in the intestinal and colonic proteome in patients with necrotizing enterocolitis (NEC) may help to characterize the disease pathology and identify new biomarkers and treatment targets for NEC.

Methods: Using gel-based proteomics, proteins in NEC-affected intestinal and colonic sections were compared with those in adjacent, near-normal tissue sections within the same patients. Western blot and immunohistochemistry were applied to crossvalidate proteomic data and histological location of some selected proteins.

Results: Thirty proteins were identified with differential expression between necrotic and vital small-intestine sections and 23 proteins were identified for colon sections. Five proteins were similarly affected in the small intestine and colon: histamine receptors (HRs), actins, globins, immunoglobulin, and antitrypsin. Two heat shock proteins (HSPs) were affected in the small intestine. Furthermore, proteins involved in antioxidation, angiogenesis, cytoskeleton formation, and metabolism were affected. Finally, secretory proteins such as antitrypsin, fatty-acid binding protein 5, and haptoglobin differed between NEC-affected and vital tissues.

Conclusion: NEC progression affects different pathways in the small intestine and colon. HSPs may play an important role, especially in the small intestine. The identified secretory proteins should be investigated as possible circulating markers of NEC progression in different gut regions.