Abstract: A method and composition is disclosed for inducing a protective immunity against HIV by inoculation with immunogens in low doses that are sufficient to induce a sustained cell-mediated response to HIV but below the amount necessary to induce an offsetting humoral response. The immunogens available for use in this method include attenuated forms of the HIV virus, subunits of the HIV virus, inactivated HIV virus and subinfectious doses of live HIV virus, all delivered at low doses. These immunogens can be prepared with-suitable carriers, adjuvants or diluents and administered either intramuscularly, mucosally (e.g., orally), intravenously or subcutaneously. The effectiveness of the initial dose of immunogen can be monitored for the presence of a sufficient cell-mediated response using a T-cell proliferation assay or an interleukin-2 assay and monitored for the lack of offsetting humoral response using commercially available ELISA assays for anti-HIV antibodies.

Abstract: An isolated bacterium of the genus Helicobacter, characterized by the 16S ribosomal RNA encoding nucleotide sequence defined in the Sequence Listing as SEQ ID NO:1 is provided. An isolated nucleic acid having the nucleotide sequence defined in the Sequence Listing as SEQ ID NO:1 is provided. Such a nucleic acid can be used for diagnosis of infection with H. hepaticus. A nucleic acid of the present invention in a vector suitable for expression of the nucleic acid is also provided. The vector can be in a host suitable for expressing the nucleic acid. A purified antigen specific for H. hepaticus is provided. A method of making an animal model for chronic Helicobacter infection is also provided.