Effect of anti-idiotype antibodies against Thomsen-Friedenreich disaccharide on proliferation of epithelial tumor cells

SENDRA VG, NORES GA, IRAZOQUI FJ

Pinamar, Argentina

Congreso; SAIB 41-X Congress Panamerican Association for Biochemistry and Molecular Biology (PABMB); 2005

EFFECT OF ANTI-IDIOTYPE ANTIBODIES AGAINST THOMSEN-FRIEDENREICH DISACCHARIDE ON PROLIFERATION OF EPITHELIAL TUMOR CELLS. Sendra, Victor G.; Nores, Gustavo A. and Irazoqui, Fernando J. CIQUIBIC (CONICET-UNC) / Department of Biological Chemistry, Faculty of Chemical Sciences, National University of Cordoba, Argentina. E-mail: vsendra@dqb.fcq.unc.edu.ar Oligosaccharide chains of mucin-type O-glycans are frequently over-expressed and aberrantly glycosylated in epithelial tumor cells. Core 1 (Galbeta1-3GalNAcalpha-O-) of mucin-type O-glycans, called Thomsen-Friedenreich disaccharide (TFD), is an example of that. Agaricus bisporus lectin (ABL) recognizes mainly TFD, showing inhibitory tumor cell proliferation property. The purpose of present project is to obtain antibodies with similar biological characteristic to ABL. Anti-idiotype antibodies was developed using ABL as first template, in rabbit. IgG anti-ABL antibodies purified by affinity chromatography reveal inhibitory ability on interaction between ABL and TFD exposing ligands. This rabbit anti-ABL IgG was used as immunogen in mice and humoral response was analysed. Raised anti-idiotype antibodies (IgG and IgM) recognize glycoproteins secreted by T47D human tumor cell line by ELISA and are inhibited by related TFD molecules. Also, they recognize T47D, MCF7 and HT29 human epithelial tumor cell lines by immunofluorescence and CellELISA. Anti-idiotype antibodies, here developed, show inhibitory activity on proliferation of HT29 and MCF7 tumor cells, with a minor efficiency that ABL. However the inhibitory effect of these anti-idiotype antibodies on tumor cell proliferation is clearly evidenced.