Immunoreactive engineered polypeptides are provided. The engineered polypeptides can be used to diagnose or induce an immune response against E. chaffeensis or E. canis.

The invention pertains to the use of VirB10 to immunize a host against an infection by a bacterium having T4SS. The invention provides a vaccine comprising VirB10, a fragment of VirB10, a polynucleotide encoding VirB10 or a polynucleotide encoding a fragment of VirB10 and a pharmaceutically acceptable carrier and/or adjuvant. The invention also provides a method of immunizing a host against an infection caused by a bacterium having T4SS, the method comprising administering to the host a vaccine of the invention. The vaccines and the methods of the invention can be used to immunize against infections caused by bacteria having T4SS in dogs, rabbits, cats, pigs, cattle, sheep, goats, deer, horses, rodents and humans.

The present invention concerns VLPT immunoreactive compositions for E. chaffeensis and compositions related thereto, including vaccines, antibodies, polypeptides, peptides, and polynucleotides. In particular, epitopes for E. chaffeensis VLPT are disclosed.

The present invention concerns gp19 immunoreactive compositions for E. canis and compositions related thereto, including vaccines, antibodies, polypeptides, peptides, and polynucleotides. In particular, epitopes for E. canis gp19 are disclosed.

Anaplasma phagocytophilum surface proteins Asp14 and OmpA and homologous genes from Anaplasmatacaea family members are used in compositions suitable for vaccines to treat or prevent infections caused by tick-born bacteria of the Anaplasmatacaea family. Asp14 and/or OmpA proteins or peptide fragments may be used in combination with other Anaplasmatacaea surface proteins to elicit an immune response. Furthermore, antibodies to Asp14 and/or OmpA proteins can be used in diagnostic methods to determine whether an individual has contracted an Anaplasmatacaea infection. Because of the conserved invasin domains in the surface proteins, a wide range of Anaplasmatacaea infections may be diagnosed, treated or prevented using compositions of the invention.

The present invention concerns gp19 immunoreactive compositions for E. canis and compositions related thereto, including vaccines, antibodies, polypeptides, peptides, and polynucleotides. In particular, epitopes for E. canis gp19 are disclosed.

The invention relates to a composition and a method for manufacturing semi-dry or dry particles containing a mucoadhesive polymer and a bioactive agent such as, but not limited to, an Immunogenic Substance (e.g., a vaccine), that allows the oral or nasal administration and delivery of the bioactive agent essentially unaltered to mucosal surfaces in the animal, including an aquatic animal.

The present invention concerns VLPT immunoreactive compositions for E. chaffeensis and compositions related thereto, including vaccines, antibodies, polypeptides, peptides, and polynucleotides. In particular, epitopes for E. chaffeensis VLPT are disclosed.

Anaplasma phagocytophilum surface protein AipA and/or fragments thereof which comprise an invasin domain are used in compositions suitable to elicit an immune response to treat or prevent infections caused by tick-born bacteria of the Anaplasmatacaea family. AipA proteins and protein fragments or antibodies directed to AipA proteins and protein fragments are also used in diagnostic assays to detect exposure to and/or infection with Anaplasmatacaea. AipA and/or fragments thereof are also used for these purposes in combination with one or both of Asp14 and OmpA proteins and/or fragments thereof which comprise an invasin domain. Homologs of these proteins are also used in the compositions and assays.

Immunoreactive engineered polypeptides are provided. The engineered polypeptides can be used to diagnose or induce an immune response against E. chaffeensis or E. canis.