Ehrlichia canis DIVA (differentiate infected from vaccinated animals)
AssigneeIDEXX Laboratories, Inc.
InventorsEugene Krah, Melissa Beall
Life of this patent
Estimating the term…
Abstract
Ehrlichia canis antigens that can be used to differentiate E. canis infected animals from animals that have been challenged with E. canis, e.g., vaccinated against E. canis, are disclosed. The invention also provides compositions and methods for determining the presence of E. canis antigens and antibodies.
Claims20
A method of distinguishing between animals that have been infected with Ehrlichia canis and animals that have not been infected with E. canis or have been vaccinated with an E. canis vaccine, the method comprising:
- (a) contacting a biological sample from an animal with a first purified E. canis polypeptide that does not specifically bind to antibodies that are a component of the animal's immune response to an E. canis vaccine;
- (b) detecting whether an antibody in the sample specifically binds to the first purified E. canis polypeptide;
- and
- wherein if an antibody in the sample specifically binds to the first purified E. canis polypeptide, then the animal is infected with E. canis and if an antibody does not specifically bind to the purified E. canis polypeptide, then the animal is either vaccinated with an E. canis vaccine or is not infected with E. canis.
A method of determining whether an animal is either not infected or has been vaccinated against E. canis with an E. canis vaccine, or is infected with E. canis comprising determining the animal's immune response to a first purified polypeptide derived from E. canis that is not an element of an E. canis vaccine and wherein the first purified polypeptide does not specifically bind to antibodies produced by the animal as a result of the vaccination with the E. canis vaccine.
A method of determining an animal's vaccination and infection status for E. canis comprising:
- (a) contacting a biological sample from an animal with a first purified polypeptide that does not specifically bind to antibodies that are a component of the animal's immune response to an E. canis vaccine and a second polypeptide that specifically binds to an antibody that is a component of the animal's immune response to an E. canis vaccine;
- (b) detecting whether antibodies in the sample specifically bind to the first and second purified polypeptides;
- (c) determining that the animal is infected by detecting the specific binding of antibodies in the sample to both the first and second purified polypeptides, determining that that the animal is vaccinated and not infected by detecting the specific binding of an antibody to the second purified polypeptide but not the first purified polypeptide, and determining that the animal is not vaccinated and not infected by detecting the absence of specific binding to the first and second purified E. canis polypeptides.
A method for determining the presence or absence of an antibody or fragment thereof, in a test sample, wherein the antibody or fragment thereof specifically binds to a purified polypeptide consisting of SEQ ID NOs:
- 2, 4, 6, 8, 10, 15, 16, or 17, comprising:
- contacting the test sample with a purified polypeptide comprising SEQ ID NOs:
- 2, 4, 6, 8, 10, 15, 16, or 17 under conditions suitable for specific binding of the purified polypeptide to the antibody or fragment thereof;
- and
- detecting the presence or absence of specific binding;
- wherein the presence of specific binding indicates the presence of the antibody or fragment thereof, and wherein the absence of specific binding indicates the absence the antibody or fragment thereof.
A composition comprising one or more purified polypeptides consisting of SEQ ID NO:16, SEQ ID NO:17, or combinations thereof.
A method of generating an immune response in an animal comprising administering one or more purified polypeptides comprising SEQ ID NOs:2, 4, 6, 8, 10, 15, 16, 17, or a combination thereof to the animal.
A method for the prophylaxis, treatment, or amelioration of an Ehrlichia canis infection in an animal comprising administering
- (a) one or more purified polypeptides comprising SEQ ID NOs:2, 4, 6, 8, 10, 15, 16, 17, or a combination thereof;
- or
- (b) one or more nucleic acids encoding one or more purified polypeptides comprising SEQ ID NOs:2, 4, 6, 8, 10, 15, 16, 17, or a combination thereof to the animal.
- (c) one or more antibodies that specifically bind one or more purified polypeptides comprising SEQ ID NOs:2, 4, 6, 8, 10, 16, 17, 18, or a combination thereof to the animal;
- whereby the E. canis infection is prevented, ameliorated, or treated.
Dependencies are inferred from the claim text.