EPITOPE ANALYSIS OF SPAN-1 AND DUPAN-2 USING SYNTHESIZED GLYCOCONJUGATES SIALYLLACT-N-FUCOPENTAOSE-II AND SIALYLLACT-N-TETRAOSE

Epitope analysis of SPan-1 and DUPAN-2 was compared with that of CA19- 9 using the synthesized glycoconjugate sialyllacto-N-fucopentaose II ( SLF II, sialyl-Lewis(a)) and its precursor, sialyllact-N-tetraose (LST a, sialyl-Lewis(c)), conjugated to human serum albumin. The CA19-9 and DUPAN-2 assay systems specifically recognized SLF II and LSTa, respec tively. The SPan-1 assay system recognized both SLF II and LSTa, altho ugh the reactivity with the former was far stronger than that with the latter. These results were, in general, compatible with those obtaine d from assaying these markers in the sera of two pancreatic cancer pat ients with definite Lewis-negative phenotype and in the sera of 39 CA1 9-9-negative pancreatic cancer patients. In conclusion, DUPAN-2 is the precursor of CA19-9 and is accumulated in the sera of pancreatic canc er patients with Lewis-negative phenotype and SPan-1 has an advantage over CA19-9 in the diagnosis of patients with Lewis-negative phenotype , although both markers have almost the same sensitivity for this mali gnancy.