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 provides methods, devices, compositions (e.g., capture complexes), and kits useful for enhancing the detection of antibodies in a test sample. The methods, devices, and compositions utilize detectable Fc-binding molecules such as Protein A, Protein G, and/or an Fc-specific antibody to amplify the signal of a detected antibody in immunoassays, such as lateral flow assays.

Neorickettsia helminthoeca is an obligate intra-cytoplasmic bacterium that causes salmon poisoning disease (SPD), an acute, febrile, fatal disease of dogs. Disclosed are compositions and methods for the immunodetection of N. helminthoeca in a canine subject. Also disclosed are immunogenic N. helminthoeca peptides that can be used in a vaccine for N. helminthoeca.

Anaplasma Marginale surface protein 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. OmpA proteins or peptide fragments may be used in combination with other Anaplasmatacaea surface proteins to elicit an immune response. Furthermore, antibodies to OmpA proteins can be used in diagnostic methods to determine whether an individual has contracted an Anaplasmatacaea infection.

The present invention discloses novel isolates of Neorickettsia risticii, compositions comprising such isolates, vaccines and methods for using such vaccines against Potomac Horse Fever.

The invention provides methods, kits, compositions, and devices useful for detection of antibodies that bind to Ehrlichia antigens and/or for differentiation of certain Ehrlichia species from others. In particular, the invention provides methods and kits useful for identifying species of Ehrlichia using populations of isolated peptides.

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.

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.

Provided herein are chimeric polypeptides that may be used, e.g., for the diagnosis of or vaccination against Ehrlichia chaffeensis and/or Ehrlichia canis.

The present invention provides compositions and methods that can be used to determine a peptide signature for an antibody repertoire in a sample comprising multiple antibodies. The method can be used to characterize a phenotype in a sample, such as providing a diagnosis, prognosis or theranosis of a medical condition.