The present invention refers to a method for the production of live attenuated bacterial strains, suitable as vaccine candidates, comprising the steps of: A. providing a bacterial strain capable of expressing glutamate racemase and possibly D-amino acid transaminase and comprising a peptidoglycan cell wall, and B. inactivating the gene or genes encoding for the glutamate racemase enzyme and, if needed, the gene or genes encoding for the enzyme D-amino acid transaminase in such way that the bacterial strain is no longer capable of expressing a functional glutamate racemase and/or a functional D-amino acid transaminase;
wherein the inactivation of said genes causes said bacterial strain to be auxotrophic for D-glutamate.

The present invention relates to immunogenic compositions, such as vaccines, comprising immunogenic polypeptides from Haemophilus influenzae and Moraxella catarrhalis, for use in methods of boosting an immune response and methods of treatment using same. More particularly, the invention relates to use of such immunogenic compositions in methods of treating or preventing exacerbation of chronic obstructive pulmonary disease.

The present invention provides antigenic polypeptides expressed during an infection by a pathogenic organism, such as Acinetobacter and compositions comprising these polypeptides. The invention further provides compositions for use in treating, preventing or detecting a bacterial infection, in particular vaccine compositions using the antigenic polypeptides. The invention further provides antibodies directed to said antigenic polypeptides.

The invention provides in part methods of treating cancers of a specific organ or tissue by administering a composition that is antigenically specific for one or more microbes that are pathogenic in the specific organ or tissue in which the cancer is situated.

The present invention provides antigenic polypeptides expressed during an infection by a pathogenic organism, such as Acinetobacter and compositions comprising these polypeptides. The invention further provides compositions for use in treating, preventing or detecting a bacterial infection, in particular vaccine compositions using the antigenic polypeptides. The invention further provides antibodies directed to said antigenic polypeptides.

The present invention provides antigenic polypeptides expressed during an infection by a pathogenic organism, such as Acinetobacter and compositions comprising these polypeptides. The invention further provides compositions for use in treating, preventing or detecting a bacterial infection, in particular vaccine compositions using the antigenic polypeptides. The invention further provides antibodies directed to said antigenic polypeptides.

The present invention relates to immunogenic compositions comprising an immunogenic polypeptide from Haemophilus influenzae or an immunogenic fragment thereof and/or an immunogenic polypeptide from Moraxella catarrhalis or an immunogenic fragment thereof, for use in the treatment or prevention of a recurrence of an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) resulting from a bacterial infection in a subject.

The present invention provides antigenic polypeptides expressed during an infection by a pathogenic organism, such as Acinetobacter and compositions comprising these polypeptides. The invention further provides compositions for use in treating, preventing or detecting a bacterial infection, in particular vaccine compositions using the antigenic polypeptides. The invention further provides antibodies directed to said antigenic polypeptides.

The present invention refers to a method for the production of live attenuated bacterial strains, suitable as vaccine candidates, comprising the steps of: A. providing a bacterial strain capable of expressing glutamate racemase and possibly D-amino acid transaminase and comprising a peptidoglycan cell wail, and B. inactivating the gene or genes encoding for the glutamate racemase enzyme and, if needed, the gene or genes encoding for the enzyme D-amino acid transaminase in such way that the bacterial strain is no longer capable of expressing a functional glutamate racemase and/or a functional D-amino acid transaminase; wherein the inactivation of said genes causes said bacterial strain to be auxotrophic for D-glutamate.

The present invention relates to the field of hyper-blebbing Gram-negative bacterial cells which are genetically modified by modifying the rpsA gene, the rpsA operon and/or 30S ribosomal protein S1 and to native outer membrane vesicles (nOMVs) obtained or obtainable from said genetically modified bacterial cells.