Synthesis and characterization of a novel glycopolymer with protective activity toward human anti-alpha-Gal antibodies.
An efficient and rapid synthesis of the derivative of the biocompatible polymer poly(styrene co-maleic acid) with Linear B disaccharide (Galili antigen) was achieved. The oligosaccharide portion was obtained by a transglycosylation reaction catalyzed by coffee bean alpha-D-galactosidase using p-nitrophenyl-alpha-D-galactopyranoside both as donor and as acceptor. The reaction was carried out in aqueous buffer without any organic cosolvent. The molar yield (30%) and the regioselectivity (82%) were significantly improved with respect to the data so far reported in the literature. The selective reduction of the p-nitrophenyl group afforded the p-aminophenyl derivative of Linear B disaccharide. Linkage of this derivative via an amidic bond to the poly(styrene co-maleic acid) was obtained by using N'-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide. The products were chemically characterized by ionspray mass spectrometry, infrared, (13)C- and (1)H-nuclear magnetic resonance. The glycopolymer specifically reacts with human serum containing antibodies and with a mixture of partially purified human IgG and IgM anti-Linear B. It efficiently protects pig kidney PK15 cells from cytotoxic effects of human serum.
Vetere
Amedeo
A
Department of Biochemistry, Biophysics and Macromolecular Chemistry, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste, Italy.
Donati
Ivan
I
Campa
Cristiana
C
Semeraro
Sabrina
S
Gamini
Amelia
A
Paoletti
Sergio
S
D000818:Animals; D000906:Antibodies / Q000276:immunology*; D001704:Biopolymers; D002240:Carbohydrate Sequence; D002460:Cell Line; D005690:Galactose / Q000276:immunology*; D006801:Humans; D019906:Nuclear Magnetic Resonance, Biomolecular; D021241:Spectrometry, Mass, Electrospray Ionization; D013552:Swine
D000906:Antibodies; D001704:Biopolymers; D005690:Galactose