Serum S-100 Protein in Stroke and Cardiac Surgery

Abstract

To the Editor: We have followed with interest the discussion regarding S-100 proteins in stroke and cardiac surgery between Drs Wong and Bonser and Drs Missler and Wiesmann. We noticed that Drs Missler and Wiesmann questioned the specificity of our Sangtec 100 LIA assay. It is correct that the validation of the Sangtec 100 LIA assay has yet to be published. A complete validation regarding specificity has, however, been performed at Sangtec Medical during development of the assay. The monoclonal antibodies used in the Sangtec 100 LIA assay are the same as in the Sangtec 100 IRMA assay, and they have been shown to be S-100B specific using the biosensor-based BIAcore system (L. Nyberg, A. Ullen, K. Haglid, E. Sandstrom, T. Stigbrand, and J. Brundell, unpublished data, 1998). In collaboration with DAKO, we have shown that recombinant human A1, A2, A4, and A6 are not detected in the Sangtec 100 LIA assay (see Figure⇓). Furthermore, calmodulin and troponin C are not measured in …