Preparation Of a Haemophilus influenzae Type B/Tetanus Toxoid Conjugate Vaccine By Reductive Amination. I-Preparation and Purification

¹Alaa Shehata, ²Yehia El Mashad, ³Amr S.M. El Sayed and ³Baheya Riad

¹Egyptian Organization for Biological Products and Vaccines (VACSERA), ²Department of Medical Biochemistry, Tanta University, ³Department Of Chemistry, Faculty of Science, Cairo University

A conjugate vaccine was prepared from the capsular polysaccharide (CPS) of Haemophilus influenzae type b (Hib) and a fraction of tetanus toxoid (TT) as a carrier protein. CPS was prepared, hydrolyzed and fractionated on a Sephadex G-50 column. The small oligosaccharide chains were collected and oxidized using sodium metaperiodate (NaIO₄). The TT fraction was prepared using Sephacryl S-300 column. Conjugation between the oxidized oligosaccharide and TT fraction was achieved by reductive amination reaction using sodium cyanoborohydride (NaBH₃CN). The resultant conjugate was purified on Sephadex G-50 column. The ratio of carbohydrate to protein was 0.1:1.