lewis-x-antigen and Down-Syndrome

It has been reported that platelet-derived growth factor B-chains homodimer (PDGF-BB) improves learning function of mice, and that sugar chain structure Lewis-X of N-glycosylated glycoprotein promotes PDGF-BB secretion from platelets. Based on these findings, we assumed that learning dysfunction in some patients with mental retardation might be due to abnormality in PDGF-BB metabolism and/or Lewis-X structure. No difference in the reactivity of PDGF-BB and Lewis-X was found between the serum of patients with mental retardation and that of normals. But sialic acid reactivity of the Lewis-X fraction in some patients was remarkably higher than that in other patients and in normals. These findings suggest that sialic acids in the Lewis-X fraction may have a relation to one of the causes of learning dysfunction in these patients.

Topics: Adult; Animals; Becaplermin; Brain; Down Syndrome; Enzyme-Linked Immunosorbent Assay; Female; Gangliosides; Humans; Intellectual Disability; Intelligence; Lewis X Antigen; Male; Mice; Platelet-Derived Growth Factor; Proto-Oncogene Proteins c-sis; Reference Values; Sialyl Lewis X Antigen