RESUMO
A promising approach capitalizing on the specific and highly sensitive characteristics of the body's own immune system is demonstrated in the context of revealing pancreatic ductal adenocarcinoma cancer (PDAC). IgA from a local biofluid called gastrointestinal lavage fluid (GLF) is used to investigate glycan reactivity to show the potential of this approach. IgA antibody responses, just as with IgG, result in amplification of a small signal which aids in detecting changes from a healthy state. IgA from GLF was screened against glycan arrays containing 609 glycan structures to investigate differential binding patterns associated with the disease. Samples included PDAC (n = 14) and non-PDAC (n = 6). Non-PDAC conditions included samples from healthy patients and the potentially confounding conditions of colon cancer and its precancerous lesion, colon adenoma. Results demonstrated characteristic reactivity in the PDAC sample group to a glycan structure. Also, IgA non-reactive motifs arose showing remarkable consistency within and between sample groups. While sample sizes are too small to identify putative biomarkers, these data show the use of IgA from GLF to be a promising avenue of research for local disease biomarker discovery.