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.

Rocky Mountain Spotted Fever (RMSF) is a vector borne disease that is caused by Rickettsia rickettsii infection. It is challenging to identify the disease in dogs and other mammals due to the cross-reacting antibodies from non-pathogenic Rickettsia spp. Provided herein are compositions and methods for detection and treatment of Rocky Mountain spotted fever (RMSF). The compositions specifically detect Rickettsia rickettsii and do not cross-react with other Rickettsia species providing rapid and accurate detection and diagnosis of RMSF.

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 provides peptide compositions and mixtures useful for the detection of antibodies that bind to Ehrlichia antigens. The peptide compositions and mixtures comprise polypeptide sequences based on an immunogenic fragment of the Ehrlichia Outer Membrane Protein 1 (OMP-1) protein. The invention also provides devices, methods, and kits comprising such peptide compositions and mixtures useful for the detection of antibodies that bind to Ehrlichia antigens and the diagnosis of monocytic and/or granulocytic ehrlichiosis.

The present invention concerns gp36 immunoreactive compositions for E. canis and gp 47 immunoreactive compositions for E. chaffeensis. In particular, epitopes for E. canis gp36 and E. chaffeensis gp 47 are disclosed. In certain embodiments, the immunoreactive compositions comprise tandem repeats having carbohydrate moieties.

The present invention provides methods of detecting analytes using particles having different physico-chemical properties, such as buoyancy, size, density, spectral characteristics, and/or binding properties, in solution-based sandwich assays and solution-based competition assays. The methods can be performed using rotors and bench-top centrifuges and provide for rapid, qualitative and quantitative detection of analytes. The present invention also provides kits that can be used to perform the methods, and mixtures containing particles suitable for the methods.

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 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 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 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.