Capsular saccharides derived from serogroups W135 and Y of Neisseria meningitidis have altered levels of O-acetylation at the 7 and 9 positions of their sialic acid residues, and can be used to make immunogenic compositions. Relative to unmodified native saccharides, derivatives of the invention are preferentially selected during conjugation to carrier proteins, and conjugates of the derivatives show improved immunogenicity compared to native polysaccharides.

Capsular saccharides derived from serogroups W135 and Y of Neisseria meningitidis have altered levels of O-acetylation at the 7 and 9 positions of their sialic acid residues, and can be used to make immunogenic compositions. Relative to unmodified native saccharides, derivatives of the invention are preferentially selected during conjugation to carrier proteins, and conjugates of the derivatives show improved immunogenicity compared to native polysaccharides.

The invention relates to the use of a polypeptide derived from the adenylate cyclase of a Bordetella sp. (CyaA-derived polypeptide) by deletion of a segment of at least 93 amino acid residues, in particular a polypeptide derived from CyaA of Bordetella pertussis, as an immunomodifying antigen of the TH1/TH17-oriented immune response in an immunogenic composition. The invention relates to a vaccine candidate comprising such CyaA-derived polypeptide, either in an acellular immunogenic composition for active immunization against a condition causally related to the infection of a host by Bordetella sp. or in a combination composition encompassing said acellular immunogenic composition.

The invention relates to the use of a polypeptide derived from the adenylate cyclase of a Bordetella sp. (CyaA-derived polypeptide) by deletion of a segment of at least 93 amino acid residues, in particular a polypeptide derived from CyaA of Bordetella pertussis, as an immunomodifying antigen of the TH1/TH17-oriented immune response in an immunogenic composition. The invention relates to a vaccine candidate comprising such CyaA-derived polypeptide, either in an acellular immunogenic composition for active immunization against a condition causally related to the infection of a host by Bordetella sp. or in a combination composition encompassing said acellular immunogenic composition.

The invention provides methods for treating or preventing microbial (eg, bacterial) infections and means for performing these methods. In particular, treatment of infections requiring rapid and durable therapy is made possible, such as for treating acute conditions such as septicemia, sepsis, SIRS or septic shock. The invention is particularly useful, for example, for treatment of microbes such as for environmental, food and beverage use. The invention relates inter alia to methods of controlling microbiologically influenced corrosion (MIC) or biofouling of a substrate or fluid in an industrial or domestic system. The invention also useful for the treatment of pathogenic bacterial infections in subjects receiving a treatment for a disease or condition, such as a transplant or a treatment for cancer, a viral infection or an autoimmune disease.

The invention describes a method of purifying polysaccharide protein conjugates using mixed mode chromatography. The method involves contacting a crude polysaccharide protein conjugate with a mixed mode resin comprising an inert porous shell and an activated core under conditions of low conductivity that allow binding of the contaminants and collecting the unbound polysaccharide protein conjugate in a flowthrough.

The invention describes a method of purifying polysaccharide protein conjugates using mixed mode chromatography. The method involves contacting a crude polysaccharide protein conjugate with a mixed mode resin comprising an inert porous shell and an activated core under conditions of low conductivity that allow binding of the contaminants and collecting the unbound polysaccharide protein conjugate in a flowthrough.

A vaccine composition for birds comprising as an active ingredient a structure containing O-antigen derived from Gram-negative bacteria, provided that said structure does not contain a whole cell, and a process for preparing the same are provided. By using a structure containing O-antigen (e.g. lipopolysaccharide) derived from Gram-negative bacteria as an active ingredient in accordance with the present invention, alleviation of inoculation reaction and reduction in an amount of injection are attained as compared to the conventional whole-cells vaccine to thereby allow for the increase in the number of other antigens to be mixed therewith.

A vaccine composition for birds comprising as an active ingredient a structure containing O-antigen derived from Gram-negative bacteria, provided that said structure does not contain a whole cell, and a process for preparing the same are provided. By using a structure containing O-antigen (e.g. lipopolysaccharide) derived from Gram-negative bacteria as an active ingredient in accordance with the present invention, alleviation of inoculation reaction and reduction in an amount of injection are attained as compared to the conventional whole-cells vaccine to thereby allow for the increase in the number of other antigens to be mixed therewith.

Immunogenic peptides, fusion polypeptides, and carrier molecules which include the immunogenic peptides, and immunogenic compositions which include these immunogenic peptides, fusion heterologous polypeptides, and/or carrier molecules bearing the peptides, and which are able to elicit antibody production against infectious organisms, are disclosed. Also disclosed are methods of making and their use in causing an antibody response against one or more strains of infectious organism, such as B. pertussis (Bp).