We Claim:
1. A hexavalent combination vaccine comprising (a) a combination of polysaccharidecarrier protein glycoconjugates of serogroups A, C, Y, W, and X of Neisseria
meningitidis; and (b) one or more proteins of serogroup B of N. meningitidis.
2. The hexavalent combination vaccine as claimed in claim 1, wherein the carrier protein
selected from diphtheria toxoid, CRM197, tetanus toxoid, pertussis toxoid, E. coli LT,
E. coli ST, and exotoxin A from Pseudomonas aeruginosa, Bacterial outer membrane
proteins such as, outer membrane complex c (OMPC), porins, transferrin binding
proteins, pneumolysis, pneumococcal surface protein A (PspA), or pneumococcal
adhesin protein (PsaA).
3. The hexavalent combination vaccine as claimed in claim 1, wherein the carrier protein
is individually conjugated to the polysaccharides of serogroups A, C, Y, W and X.
4. A method of preparing the polysaccharide-carrier protein glycoconjugates of
serogroups A, C, Y, W, and X of Neisseria meningitidis as claimed in anyone of claims
1-3 comprises the steps of:
a) cultivating meningitis serogroup strains A, C, Y, W and X in presence of complex
media for about 12–20 hours to produce meningococcal A, C, Y, W, and X
polysaccharides;
b) purifying the meningococcal A, C, Y, W, and X polysaccharides by processes
selected from ultrafiltration, cetyl-trimethylammonium bromide (CTAB)
precipitation, centrifugation, depth filtration, ethanol, and salt precipitation;
c) activating each of the purified meningococcal A, C, Y, W, and X polysaccharides
at an alkaline pH of 8.5–9.5 in the presence of 1-Cyano -4 Dimethylaminopyridine
Tetrafluoroborate (CDAP) and at a temperature ranging from 8-15 oC;
d) activating or derivatizing the carrier protein by 1-ethyl-3-(dimethylaminopropyl)-
carbodiimide (EDAC) for about 16–24 hours;
e) mixing and conjugating the activated A, C, Y, W, and X polysaccharides and the
activated carrier proteins to obtain the polysaccharide-carrier protein
glycoco