Human serum amyloid A3 peptide enhances intestinal MUC3 expression and inhibits EPEC adherence

Biochem Biophys Res Commun. 2003 Jan 10;300(2):531-40. doi: 10.1016/s0006-291x(02)02901-7.

Abstract

We previously determined that the N-terminal region of bovine mammary-associated serum amyloid A3 (M-SAA3) increased intestinal mucin MUC3 levels in HT29 human intestinal cells by approximately 2.5-fold, relative to untreated cells. This study shows that the human M-SAA3 N-terminal peptide further enhances MUC3 transcript levels by approximately 4.3-fold in these cells (p<0.02), implicating a species-specific interaction. Furthermore, immunofluorescence and immunoblot analysis using a MUC3-specific monoclonal antibody confirms that the human M-SAA3 peptide stimulates MUC3 protein expression and secretion by the HT29 cells. More importantly, pretreatment of the cells with the peptide causes a subsequent 73% decrease in the adherence of enteropathogenic Escherichia coli (EPEC) to these cells, relative to untreated cells (p<0.01). The intestinal mucin MUC3 has been shown to provide a protective barrier in the gut and inhibit adherence of pathogens to the gut wall. Therefore, a means to increase MUC3 protein expression by a colostrum-associated peptide or protein may be a highly effective prophylactic treatment for the prevention of gastrointestinal diseases such as necrotizing enterocolitis and infectious diarrhea.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bacterial Adhesion / drug effects*
  • Cattle
  • Cell Line
  • Dose-Response Relationship, Drug
  • Escherichia coli / drug effects
  • Escherichia coli / pathogenicity*
  • Gene Expression Regulation / drug effects
  • Humans
  • Intestinal Mucosa / drug effects
  • Intestinal Mucosa / metabolism
  • Intestinal Mucosa / microbiology*
  • Kinetics
  • Microscopy, Fluorescence
  • Mucin-3
  • Mucins / biosynthesis*
  • Mucins / chemistry
  • Mucins / genetics
  • Peptides / chemistry
  • Peptides / pharmacology
  • RNA, Messenger / biosynthesis
  • Serum Amyloid A Protein / chemistry
  • Serum Amyloid A Protein / pharmacology*

Substances

  • Mucin-3
  • Mucins
  • Peptides
  • RNA, Messenger
  • SAA3P protein, human
  • Serum Amyloid A Protein