Lectin UEA-I-binding proteins are specifically increased in the squamous epithelium of patients with Barrett's esophagus.

BACKGROUND

Chronic gastritis and esophagitis are associated with changes in mucosal glycosylation patterns. Lectins represent a group of specific carbohydrate binding proteins that can be used as sensitive tools for the analysis of glycosylation patterns.

AIM: To investigate the binding patterns of lectins Ulex europaeus agglutinin-I (UEA-I), Dolichos biflorus agglutinin (DBA), Helix pomatia agglutinin (HPA) and peanut agglutinin (PNA) at the gastroesophageal junction in nonerosive (NERD), erosive reflux disease (ERD) and Barrett's esophagus (BE).

METHODS

One hundred and twenty-two patients (female n = 53; male n = 69; controls n = 28; NERD n = 36; ERD n = 24 and BE n = 34) were included in this study. The binding patterns of lectins were examined immunohistochemically at the squamocolumnar junction, in squamous epithelium and columnar-lined epithelium. Staining patterns of lectins were semiquantitatively evaluated using an immunohistochemical score and the data were analyzed using non-parametric tests.

RESULTS

BE, as compared to the controls, was associated with specific lectin-binding patterns: lectin binding of UEA-I and DBA were significantly decreased at the superficial (p = 0.012; p = 0.00036, respectively) and at the deep glandular body (p = 0.045; p = 0.055, respectively). Comparisons of lectin-staining scores between GERD and BE revealed significant increases of UEA-I in both the stratum superficiale (p = 0.0155) and stratum spinosum (p = 0.0048) of SE in patients with BE. Notable, this change was specific for patients with BE, while no difference was observed between patients with GERD and controls.

CONCLUSION

We found two major types of lectin-binding patterns. First, lectin-binding characteristics associated with GERD in general, and second, lectin-binding patterns which were specific for BE. Lectin UEA-I-binding proteins were specifically increased in the squamous epithelium of patients with BE. Thus, UEA-I may serve as a potential marker for BE, especially in patients with short segment BE.