An in vitro assay for pancreatic ductal adenocarcinoma, preferably an immunoassay, is based on the determination of anti-ezrin auto-antibodies in a biological sample from a subject suspected of being affected by pancreatic ductal adenocarcinoma or from a subject whose predisposition to pancreatic ductal adenocarcinoma one desires a determination.

The present disclosure contemplates detecting and treating a pathological condition, such as intestinal ischemia such as acute mesenteric ischemia, necrotizing enterocolitis, inflammatory bowel disease, and bowel graft rejection in a subject's intestinal tract. The methodology comprises obtaining a sample from the subject; detecting whether an analyte such as Villin-1, -glutathione S-transferase, or intestinal fatty acid binding protein (I-FABP) is present in the sample by contacting the sample with an anti-analyte antibody and detecting binding between analyte and the antibody; and diagnosing the subject with the condition when, for example, the presence of analyte in the sample is detected and exceeds the level of analyte in a healthy control sample. A superparamagnetic bead includes an anti-Villin-1 antibody; an anti--glutathione S-transferase antibody, or an anti-intestinal-fatty acid binding protein (I-FABP) antibody. A superparamagnetic bead comprising a surface coating that binds Villin-1, -glutathione S-transferase, or intestinal-fatty acid binding protein (I-FABP).