Alterations of the sugar moiety of Tamm-Horsfall protein in children with malignancies of lymphoid cells

The aim of this study was to examine whether the sugar moiety of Tamm-Horsf all protein (THP) is affected by pathological processes caused by acute lym phoblastic leukemia (ALL) or non-Hodgkin's lymphoma (NHL). The carbohydrate part of THP was studied by monosaccharide analysis, N-glycan profiling, an d reactivity with specific lectins. Our results have shown that THP of ALL or NHL patients, in comparison with healthy subjects, have modified sugar c hains. This is expressed in lower contents of N-acetyl-galactosamine, alpha 2,6-linked sialic acid and alpha 1,6-linked fucose as well as in altered p roportions of various N-glycans. We have shown that pathological processes also affect the carbohydrate unit of human immunoglobulin G (IgG) isolated from sera of ALL or NHL patients. As compared with healthy subjects, in IgG of the patient group, lower amounts of sialic acid and fucose were observe d. These changes did not influence the biological properties of THP as judg ed by their unaltered ability to bind with interleukin-1 alpha, alpha(1)-ac id glycoprotein, serum albumin, transferrin, IgG(1) and the light and heavy chains of IgG. Neither the in vivo alterations of IgG caused by ALL or NHL nor its in vitro modifications influence the interaction between IgG and T HP.