PSA is delivered to the host by outer membrane vesicles (OMVs), secretion structures that target bacterial molecules to host cells. Purified OMVs direct the in vitro differentiation of functional Tregs with potent suppressive activity in a PSA dependent manner. Treatment of animals with OMVs containing PSA prevents experimental colitis and suppresses pro-inflammatory cytokine responses in the gut, and indicate that compositions, medicaments, and methods useful for the treatment of inflammation, and more particularly, inflammatory bowel diseases.

Provided herein are methods and compositions related to Prevotella EVs useful as therapeutic agents.

The invention relates to generation and use of cellular and humoral responses for the prevention and treatment of P. gingivalis related conditions and diseases.

An immunogenic composition, a periodontal vaccine formulation containing the immunogenic composition, and methods for treating or preventing periodontal disease are provided, where the methods involves administering an immunologically effective amount of the composition or vaccine formulation to a subject. The immunogenic composition contains at least one polypeptide that comprises: an Mfa1 antigen sequence that is substantially homologous to an immunogenic amino acid sequence from an Mfa1 fimbrilin protein of a Porphyromonas bacterium; and an HA1 antigen sequence, an HA2 antigen sequence, or both an HA1 antigen sequence and an HA2 antigen sequence, wherein the HA1 antigen sequence is substantially homologous to an immunogenic amino acid sequence from an RgpA Gingipain hemagglutinin domain 1 contained within an RgpA Gingipain protein of a Porphyromonas bacterium, and the HA2 antigen sequence is substantially homologous to an immunogenic amino acid sequence from an RgpA Gingipain hemagglutinin domain 2 contained within an RgpA Gingipain protein of a Porphyromonas bacterium.

This invention relates to the delivery of heterologous peptides or proteins such as therapeutic peptides, therapeutic proteins or antigens to mucosal sites using vesicles derived from the outer membrane of commensal bacteria, recombinant bacteria capable of producing such vesicles, and methods for the production of such vesicles. The invention further relates to an inducible expression system for use in recombinant bacteria.

Provided herein are methods and compositions related to treating or preventing seizures. In some aspects, provided herein are methods of treating or preventing seizures in a subject by administering to the subject a composition comprising Parabacteroides and Akkermansia bacteria.

An immunogenic composition, a periodontal vaccine formulation containing the immunogenic composition, and methods for treating or preventing periodontal disease are provided, where the methods involves administering an immunologically effective amount of the composition or vaccine formulation to a subject. The immunogenic composition contains at least one polypeptide that comprises: an Mfa1 antigen sequence that is substantially homologous to an immunogenic amino acid sequence from an Mfa1 fimbrilin protein of a Porphyromonas bacterium; and an HA1 antigen sequence, an HA2 antigen sequence, or both an HA1 antigen sequence and an HA2 antigen sequence, wherein the HA1 antigen sequence is substantially homologous to an immunogenic amino acid sequence from an RgpA Gingipain hemagglutinin domain 1 contained within an RgpA Gingipain protein of a Porphyromonas bacterium, and the HA2 antigen sequence is substantially homologous to an immunogenic amino acid sequence from an RgpA Gingipain hemagglutinin domain 2 contained within an RgpA Gingipain protein of a Porphyromonas bacterium.

The invention provides compositions comprising bacterial strains for treating and preventing inflammatory and autoimmune diseases.

The present invention concerns a composition comprising at least one prophylactically or therapeutically active agent selected from the group consisting of attenuated Porphyromonas gingivalis, inactivated Porphyromonas gingivalis, a subunit of Porphyromonas gingivalis, a recombinant or isolated immunogenic polypeptide or peptide from Porphyromonas gingivalis or a c DNA from Porphyromonas gingivalis, for use as a vaccine for preventing or treating periodontitis, diabetes, obesity and/or complications thereof in a subject. The present invention also concerns an isolated antibody having specificity for Porphyromonas gingivalis for use for preventing or treating periodontitis, diabetes, obesity and/or complications thereof in a subject.

Methods of and compositions for breaking down a biofilm or inhibiting, preventing or treating a microbial infection that produces a biofilm are disclosed, which involves administration of an interfering agent capable of specifically competing, titrating, or inhibiting the binding of an HU protein to a microbial DNA. By competing with HU proteins that bind to DNA scaffold in the biofilm, these interfering agents destabilize the biofilm leading to destruction and removal of the biofilm by the immune system. Further method and composition aspects are contemplated in relation to infections caused by bacteria that export an HU protein.