Supplier-dependent antiglycan monoclonal antibody specificities: Comment on “High-throughput carbohydrate microarray profiling of 27 antibodies demonstrates widespread specificity problems”

We recently reported carbohydrate microarray profile results for a set of commercially available antiglycan monoclonal antibodies (Manimala et al. 2007), including clone A70-C/C8 (Kuemmel et al. 2007), which we acquired from Cell Sciences (Canton, MA), and antibodies B386 and B389, which we acquired from Biomeda (Foster City, CA). It was our understanding that B386 was equivalent to A68-B/A11 (Karsten et al. 1995) and B389 was equivalent to A70-A/A9 (Christensen et al. 2007). Subsequent to publication, we obtained A70-C/C8, A68-B/A11, and A70-A/A9 from the original source, Glycotope GmbH, Berlin-Buch (Dr. Uwe Karsten). In a side-by-side comparison, two of the antibodies supplied by Glycotope produced significantly different results as compared to the antibodies from Cell Sciences and Biomeda. In our assay, antibody A70-C/C8 from Glycotope bound selectively to LeY while A70-C/C8 from Cell Sciences cross-reacted with blood group B as we had reported. Antibody A68-B/A11 from Glycotope displayed reactivity with TFα, GA1 (TFβ), blood group A, blood group B, blood group H1, GM1, and tri-LacNAc while B386 from Biomeda bound blood group B had minor reactivity with blood group A trisaccharide and did not bind TFα, GA1 (TFβ), blood group H1, GM1, or tri-LacNAc. Antibody A70-A/A9 from Glycotope and B389 from Biomeda both bound selectively to LeY and did not show appreciable differences. Based on these results, binding data, tissue staining, and Western blots obtained with a particular antibody should be interpreted in relation to the supplier. Table ​TableII lists the original sources and catalog numbers for the antibodies profiled in our previous paper (Manimala et al. 2007). Table I Sources and catalog numbers for the antibodies