Fig. 3.
ST3Gal I-IV sialyltransferase deficiencies result in differential degrees of exposed galactose and selectin–immunoglobulin chimera binding to blood neutrophils.
(A) RCA-I, ECA, and PNA lectin binding to circulating Gr1+cells (mostly neutrophils) or CD8+ T cells was assessed by flow cytometry. Reduced sialylation resulting in exposed β-linked galactose was observed differentially among leukocytes and specific sialyltransferase mutations. (B) P- and E-selectin–immunoglobulin chimera binding to circulating Gr1+ leukocytes of mice deficient in ST3Gal-I, -II, -III, and -IV was analyzed by flow cytometry and compared with C2GlcNAcT-I deficiency. Panels A and B are representative of 3 separate experiments. Filled histograms represent selectin binding to neutrophils of mutant mice and are compared with wild-type littermates in the same panel.