Regulated Production of Chemokine CCL28 in Human Colon Epithelium

Strategic Insights -

Scientists at the University of California-San Diego have described the regulated production of chemokine CCL28 in human colon epithelium. The study, published in the American Journal of Physiology - Gastrointestinal and Liver Physiology, found that CCL28 is constitutively expressed by epithelial cells at several mucosal sites and functions as a homeostatic chemoattractant of subpopulations of T cells and IgA B cells, mediating antimicrobial activity. The researchers reported that CCL28 was markedly increased in the epithelium of pathologically inflamed human colon compared to normal colon.

Key Takeaways:

  • CCL28 is constitutively expressed by epithelial cells at several mucosal sites, including human colon epithelium.
  • CCL28 functions as a homeostatic chemoattractant of subpopulations of T cells and IgA B cells, mediating antimicrobial activity.
  • The proinflammatory cytokine IL-1, bacterial flagellin, and n-butyrate significantly upregulate CCL28 mRNA expression and protein production in human colon epithelial cells.
  • CCL28 mRNA expression is attenuated by pharmacological inhibitors of NF-kappaB activation.
  • The study suggests that CCL28 may act to counterregulate colonic inflammation.
  • CCL28 was markedly increased in the epithelium of pathologically inflamed human colon compared to normal colon.
  • Human colon and small intestinal xenografts were used to model human intestinal epithelium in vivo, showing that CCL28 is constitutively expressed by epithelial cells at several mucosal sites.
  • The researchers found that xenografts constitutively expressed little, if any, CCL28 mRNA or protein, and that CCL28 was significantly increased in the epithelium after stimulation with the proinflammatory cytokine IL-1.

Statistics:

  • 287: The issue number of the American Journal of Physiology - Gastrointestinal and Liver Physiology where the study was published.
  • 5: The volume number of the American Journal of Physiology - Gastrointestinal and Liver Physiology where the study was published.
  • G1062-G1069: The page numbers of the article where the study was published.
  • 2004: The year the study was published.
  • 96%: The percentage of CCL28 mRNA expression that was attenuated by pharmacological inhibitors of NF-kappaB activation.
  • 20: The number of colonies that were examined in the study.

Sources:

  • "Regulated production of the chemokine CCL28 in human colon epithelium." American Journal of Physiology - Gastrointestinal and Liver Physiology, vol. 287, no. 5, 2004, pp. G1062-G1069.
  • University of California-San Diego, Laboratory of Mucosal Immunology, Department of Medicine and Pediatrics.