title: Increased GD3 ganglioside in plasma of children with T-cell acute lymphoblastic leukemia.
abstract: The presence of tumor-associated GD3 in the plasma of 12 patients with T-cell acute lymphoblastic leukemia (T-ALL) was determined utilizing microscale ganglioside isolation and thin layer chromatography (TLC) immunodetection with an anti-GD3 monoclonal antibody, R24. Immunostaining of control plasma gangliosides revealed two nearly equal subspecies groups of GD3, GD3U and GD3L. Plasma from those T-ALL patients with a high R24-positive lymphoblast count (> 60,000/mm3) had a significant increase in total GD3 and each of the GD3 subspecies groups, and a disproportionate increase in GD3L resulted in an increased ratio GD3L/GD3U in these samples. In contrast, total GD3, GD3 subspecies, and GD3L/GD3U was not increased in plasma from those cases with low R24-positive blast count (< 20,000/mm3) or in pre-B ALL plasma. The altered GD3 content in R24-positive T-ALL plasma was reversible, since total GD3 and GD3L/GD3U in plasma from a patient in remission from R24-positive T-ALL was near that of controls. Resorcinol staining of TLC-separated gangliosides confirmed the results observed with R24 detection methods. The results strongly suggest that GD3 is shed in vivo from T-ALL blasts in patients with R24-positive T-ALL, resulting in both qualitative and quantitative changes in circulating GD3 in these patients.
authors.affiliation: Center for Cancer and Transplantation Biology, Children's National Medical Center, Washington, D.C. 20010.
authors.forename: W D
authors.initials: WD
authors.lastname: Merritt
authors.forename: V
authors.initials: V
authors.lastname: Der-Minassian
authors.forename: G H
authors.initials: GH
authors.lastname: Reaman
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood; D002648:Child; D002855:Chromatography, Thin Layer; D005732:Gangliosides / Q000097:blood* / Q000302:isolation & purification; D006801:Humans; D007124:Immunoenzyme Techniques; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; D005732:Gangliosides; C026226:ganglioside, GD3