Serum amyloid P component is the Shiga toxin 2-neutralizing factor in human blood.
It has been suggested that some factor present in human plasma binds to Shiga toxin 2 (Stx2) and neutralizes it in vitro (Bitzan, M., Klemt, M., Steffens, R., and Muller-Wiefel, D. E. (1993) Infection 21, 140-145). This factor does not exist in other species (Caprioli, A., Luzzi, I., Seganti, L., Marchetti, M., Karmali, M., Clarke, I., and Boyd, B. (1994) Recent Adv. VTEC Infect. 353-356). Because analysis of this factor is important to understanding the pathology induced by Shiga toxin-producing Escherichia coli, we purified this factor from human plasma and identified it. Purification was carried out by serially subjecting human plasma to Con A-Sepharose, DEAE-Sepharose, hydroxyapatite, and gel-filtration high performance liquid chromatography (HPLC), using Stx2-neutralizing activity as the indicator. The gel-filtration HPLC fraction yielded a single band on SDS-polyacrylamide gel electrophoresis. Twenty N-terminal amino acid residues of this fraction were analyzed and found to correspond perfectly to human serum amyloid P component (HuSAP). Because commercially available HuSAP also showed Stx2 binding and neutralizing activity, we identified this factor as HuSAP.
Kimura
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Teijin Institute for Biomedical Research, Teijin Ltd., 4-3-2, Asahigaoka, Hino City, Tokyo 191-8512, Japan. t.kimura@teijin.co.jp
Tani
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S
Matsumoto Yi
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Y
Takeda
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D000595:Amino Acid Sequence; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008969:Molecular Sequence Data; D000683:Serum Amyloid P-Component / Q000302:isolation & purification* / Q000494:pharmacology; D022641:Shiga Toxin 2 / Q000037:antagonists & inhibitors*
D000683:Serum Amyloid P-Component; D022641:Shiga Toxin 2