Embodiments concern methods and compositions for treating or preventing a bacterial infection, particularly infection by a Staphylococcus bacterium. Aspects include methods and compositions for providing a passive immune response against the bacteria. In certain embodiments, the methods and compositions involve an antibody that binds Coagulase (Coa). Further aspects relate to immunogenic compositions comprising at least one Staphylococcal coagulase R Domain, wherein the R Domain is 80% identical in sequence to a R Domain.

Compositions and methods of the present invention prevent, inhibit or reduce the toxic effects of proteins and toxins secreted from microbes. A method for neutralizing microbial protein products in a subject comprises administering a composition to the subject, said composition comprising plasma-derived IgM and optionally one or more excipients in a pharmaceutical carrier, wherein the composition is administered in an amount effective to neutralize the microbial protein products.

The invention is in the field of therapy of antibody deficiencies. Inventors demonstrate for the first time in both controls and IgA-deficient patients, systemic anti-microbiota IgG responses correlate with reduced inflammation suggesting that systemic IgG responses contribute to the gut microbiota confinement. Furthermore, SIgAd-associated inflammation is inversely correlated with systemic anti-commensal IgG responses, which may thus serve as a second line of defense. Altogether, these data suggest that systemic IgG and intestinal IgA cooperate in different body compartments to limit systemic pro-inflammatory pathways. As selective IgA deficient patients harbour elevated seric anti-commensal IgG levels, these findings suggest that in selective IgA deficiency, microbiota confinement is obtained at the price of a strong inflammatory response. Accordingly, the invention relates to a composition containing immunoglobulins A (IgA), more particularly secretory IgA, for use by oral administration in the prevention or treatment of antibody deficiencies such as SIgAd (Selective IgA deficiency) or common variable immunodeficiency (CVID) and associated inflammatory diseases.

Disclosed are novel immunogenic proteins derived from Staphylococcus aureus, as well as methods for their use in conferring protective immunity against S. aureus infections. Also disclosed are nucleic acids encoding the proteins and methods of use of these nucleic acids.

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.

Materials and methods are provided for treatment and/or prevention of Staphylococcal diseases and disorders such as infection and dermal inflammation.

Antibodies having Fab regions that specifically bind to Staphylococcus aureus protein A are capable of mediating opsinization of Staphylococcus aureus bacteria despite their expression of antibody-neutralizing protein A. These antibodies and antigen-binding fragments thereof can be used in methods of treating and/or preventing Staphylococcus aureus infections.

Described herein are engineered microbe-targeting or microbe-binding molecules, kits comprising the same and uses thereof. The microbe-targeting or microbe-binding molecules can comprise a microbe surface-binding domain linked to a portion of an Fc region. Further, the microbe-targeting molecules can be conjugated to substrate (e.g., a magnetic particle) to form a microbe-targeting substrate. Such microbe-targeting molecules and/or substrates and the kits comprising the same can be used in various applications, such as diagnosis and/or treatment of an infection caused by microbes. Moreover, the microbe-targeting molecules and/or substrates can be easily regenerated after use.

A pharmaceutical composition comprising an agent that increases the expression of a purR gene in a bacterium and a method of attenuating, preventing or treating a bacterial infection in a subject comprising administering to the subject an agent that increases the expression of a purR gene.

The invention relates to the compositions of synthetic oligo-γ-(1.fwdarw.6)-2-amino-2-deoxy-D-glu-copyranosides conjugated to carriers, and methods for making and use same.