title: Enzyme-linked immunoadsorbent assay (ELISA) for calcium-binding protein of human small intestine. A quantitative method for measuring calcium-binding protein in small intestinal biopsies.
abstract: A method for measuring calcium-binding protein (CaBP) in small intestinal biopsies of the human is reported. The assay is performed as a competitive enzyme-linked immunoadsorbent assay (ELISA). Pure CaBP and a cytosol fraction of human jejunum generate competitive displacement curves running in parallel thus demonstrating the antigen specificity of the assay. Non-specific displacement of anti-CaBP antibodies from the solid phase CaBP is negligible as demonstrated by the inability of cytosolic proteins of rat small intestine to produce a detectable response in the assay. The method has a detection limit of 3 ng CaBP (applied in 150 microliter) and a coefficient of variation of 9.8%. The ELISA method is applicable in the study of the role of CaBP in clinical disorders of the small bowel.
mesh_terms: D000818:Animals; D017317:Annexin A6; D001667:Binding, Competitive; D002135:Calcium-Binding Proteins / Q000032:analysis*; D003600:Cytosol / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007421:Intestine, Small / Q000032:analysis*; D011786:Quality Control; D051381:Rats
chemical_list: D017317:Annexin A6; D002135:Calcium-Binding Proteins