The carbohydrate-binding properties of the leech anticoagulant antistasin indicated that the protein binds with high affinity to the glycolipid sulfatide. Comparisons of the amino acid sequences of antistasin and other sulfatide or heparin-binding proteins revealed at 14 amino acid region of homology. For example, sequence homologies occur in thrombospondin, von Willebrand factor, beta-2-glycoprotein 1, and collagen Type IV, all of which bind heparin and/or sulfatide. Homologies were also found with coat proteins from malaria circumsporozoites and Herpes simplex I, and the alternate complement pathway protein, properdin. The mannose binding protein has been purified to homogeneity. This protein binds with high affinity to Lc3Cer (GlcNAc-beta-l-3Gal-beta-4-beta-l-- Iceramide) and-nLc5Cer (GlcNAc-beta-l-3Gal-beta-l- 4GlcNAc-beta-l-4Gal- beta-l- 4Glc-beta-lceramide) and can be used as a probe to determine the level of these substances in tissues. This technique was utilized to demonstrate that one sample of chronic myeloid leukemia cells contains both Lc3Cer and nLc5Cer.
