Antigens capsular

B. L. Reuhs, R. W. Carlson, and J. S. Kim, Rhizobium fredii and Rhizobium meliloti produce 3-deoxy-D-marmo-2-octulosonic acid-containing polysaccharides that are structurally analogous to group II K antigens (capsular polysaccharides) found in Escherichia coli, J. Bacteriol., 175 (1993) 3570-3580. 

Vaccines can be roughly categorized into killed vaccines and Hve vaccines. A killed vaccine can be (/) an inactivated, whole microorganism such as pertussis, (2) an inactivated toxin, called toxoid, such as diphtheria toxoid, or (J) one or more components of the microorganism commonly referred to as subunit vaccines. The examples are capsular polysaccharide of Streptococcus pneumoniae and the surface antigen protein for Hepatitis B vims vaccine. 

In the cell-wall antigen from Staphylococcus aureus M, taurine is linked as an amide (51) to a 2-acetamido-2-deoxy-D-galactosyluronic residue. l-Threonine and L-glutamic acid are linked as amides to D-glucuronic acid residues in the LPS from Rhodopseudomonas sphaeroides ATCC 17023 and in the capsular polysaccharide from Klebsiella K82, respectively. In the capsular polysaccharide from E. coli K54, L-serine and L-threonine, in the ratio 1 9, are linked to the carboxyl group of a D-glucuronic acid residue. In the capsular polysaccharide from Haemophilus influenzae type d,... 

In different polysaccharides of the teichoic acid type, monosaccharides or oligosaccharides are connected by phosphoric diester linkages. Two examples are the capsular antigens from Neisseria meningitides type A (56) and Haemophilus influenzae type c (57), respectively. Glycerol phosphate... 

Typhoid Vi capsuiar poiysaccharide antigen Cultures of Sai typhi grown in liquid medium Extraction of capsular antigen Estimation of capsular antigen ... 

A structural study on lipid A and the O-specific polysaccharide of the lipopoly-saccharide from a clinical isolate of Bacteroides vulgatus from a patient with Crohn s disease was conducted by Hashimoto and coworkers [39]. They separated two potent virulence factors, capsular polysaccharide (CPS) and lipopolysaccharide (LPS), from a clinical isolate of B. vulgatus and characterized the structure of CPS. Next, they elucidated the strucmres of O-antigen polysaccharide (OPS) and lipid A in the LPS. LPS was subjected to weak acid hydrolysis to produce the lipid A fraction and polysaccharide fraction. Lipid A was isolated by PLC, and its structure was determined by MS and NMR. 

There are two pneumococcal vaccines, a 7-valent conjugated vaccine for children younger than 6 years of age and a 23-purified-capsular polysaccharide antigen vaccine for adults. The 23 capsular types in the vaccine represent at least 85% to 90% of the serotypes that cause invasive pneumococcal infections among children and adults in the United States.41 After vaccination, an antigen-specific antibody response, indicated by a twofold or greater rise in serotype-specific antibody, develops within 2 to 3 weeks in 80% or more of healthy young adults.42... 

Anderson, P.W., Pichichero, M.E., Stein, E.C., Porcelli, S., Betts, R.F., Connuck, D.M., Korones, D., Insel, R.A., Zahradnik, J.M., and Eby, R. (1989) Effect of oligosaccharide chain length, exposed terminal group, and hapten loading on the antibody response of human adults and infants to vaccines consisting of Haemophilus influenzae type b capsular antigen uniterminally coupled to the diphtheria protein CRMI97./. Immunol. 142, 2464-2468. 

Antigen found in the sterile filtrate of B. anthracis Purified capsular polysaccharide of... 

The C-substance is a species-specific antigen of Streptococcus pneumoniae that often contaminates the type-specific capsular poly-... 

A brief overview of the biosynthesis of KDO, and its incorporation into LPS, is found in a paper by Heath s group.1 Some aspects of KDO are discussed in chapters on somatic and capsular antigens of Gramnegative bacteria by Liideritz and coworkers.2 3 The early work on KDO has been reviewed in a chapter on the carbohydrates of bacterial LPS by Ashwell and Hickman.4 Selected papers concerning KDO... 

The first report of the occurrence of KDO in a structure other than LPS was that of Taylor47 on the capsular polysaccharide (K-antigen) of a clinical isolate, Escherichia coli LP1092. Almost simultaneously, Bhattachaijee and coworkers83 described an exopolysaccharide from Neisseria meningitidis serogroup 29e. This material contains KDO... 

Biochemistry, Vol. 26A, Somatic and Capsular Antigens of Gram-Negative Bacteria, p. 105. Elsevier, Amsterdam, 1968. 

Despite their popularity, aluminium-based adjuvants suffer from several drawbacks. They tend to effectively stimulate only the humoral arm of the immune response. They cannot be frozen or lyophylized, as either process promotes destruction of their gel-based structure. In addition, aluminium-based products display poor or no adjuvanticity when combined with some antigens (e.g. typhoid or Haemophilus influenzae type b capsular polysaccharides). 

It is prepared from purified pneumococcal capsular antigens and includes 23 serotypes which are responsible for at least 85% of pneumococcal infections and has greater than 90% coverage against serotypes that are penicillin resistant. 

Modem subunit vaccines contain one or more selected antigenic subunits that have been found to provide protection against a particular pathogen. They are better defined from a physicochemical aspect and have fewer side effects than vaccines, which contain intact cells, whether inactivated or attenuated. Current subunit antigens include viral and bacterial proteins as well as bacterial capsular polysaccharides. 

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