Aquaporin 2 protects cattle from ticks and tick-borne parasites
Inventors
Scoles, Glen A. • Guerrero, Felicito • Bastos, Reginaldo
Assignees
US Department of Agriculture USDA • Washington State University WSU
Publication Number
US-10052369-B2
Publication Date
2018-08-21
Expiration Date
2036-06-09
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
A novel method of using an aquaporin protein from Rhipicephalus microplus (RmAQP2), fragments of RmAQP2, and/or the cDNA encoding RmAQP2 and/or the fragments are described. Immunogenic composition containing recombinant RmAQP2 and/or fragments of RmAQP2 are produced and administered to an ungulate which generates an immune response to RmAQP2. After feeding female ticks on the ungulate injected with RmAQP2 and/or fragments of RmAQP2, the female ticks have lower reproductive viability because of a reduced egg mass, reduced hatching percentage, and reduced survival of larvae. Thus, administering RmAQP2 and/or RmAQP2 fragments to an ungulate can reduce the incidence of R. microplus and also reduce the incidence of tick-borne pathogens in ungulates because of the lower number of R. microplus.
Core Innovation
The invention relates to the discovery and use of a novel aquaporin protein from Rhipicephalus microplus known as RmAQP2, including fragments and cDNA encoding this protein. The invention provides immunogenic compositions containing recombinant RmAQP2 and/or its fragments, which when administered to ungulates, induce an immune response against RmAQP2. This immune response results in female ticks feeding on the immunized ungulate having reduced reproductive viability, evidenced by decreased egg mass, lower hatching percentages, and reduced larval survival.
The immunogenic compositions serve to reduce the incidence of R. microplus infestation in ungulates, thereby lowering the number of ticks that can transmit tick-borne pathogens, such as Babesia bovis. The protective effect is achieved by targeting the aquaporin 2 protein expressed in tick salivary glands, which plays a crucial role in osmoregulation during the tick feeding cycle. The invention further contemplates using polynucleotides encoding RmAQP2, expression vectors with heterologous promoters, recombinant organisms expressing RmAQP2, and kits comprising these components for administration to ungulates.
The problem being addressed stems from the economic importance of R. microplus as a vector of Babesia bovis, the causative agent of bovine babesiosis, and the limitations of existing tick control measures. Current methods rely mainly on acaricides and live attenuated vaccines, which have inconsistent efficacy and face challenges such as acaricide resistance and the reemergence of ticks in previously free areas. There exists a need for more effective vaccines that reduce tick populations and interrupt pathogen transmission, particularly by impeding tick feeding and reproductive success.
Claims Coverage
The patent includes six independent claims focusing on immunogenic compositions and kits leveraging RmAQP2 and its fragments to stimulate an immune response that reduces tick viability and disease transmission.
Immunogenic composition containing RmAQP2 or its peptides
An immunogenic composition comprising a pharmaceutically acceptable carrier and a Rhipicephalus microplus immunogen present in an effective amount to stimulate an immune response in ungulates. The immunogen is selected from specific aquaporin 2 sequences (amino acids 3-293 of SEQ ID NO: 2), proteins with at least 95% identity to this sequence, SEQ ID NO: 7, SEQ ID NO: 9, specific peptides of SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 27, or combinations thereof, and carriers include phosphate buffered saline and various pharmaceutically acceptable carriers.
Inclusion of adjuvants in the immunogenic composition
The immunogenic composition further comprises an adjuvant selected from a group including saponin, mineral oil, vegetable oil, various emulsions, aluminum compounds, squalene and analogs, Freund's adjuvants, muramyl dipeptide, monophosphoryl lipid A, polyphosphazine, bacterial toxins, CpG motif-containing oligonucleotides, and their combinations.
Kit containing RmAQP2 immunogen and optionally carrier and adjuvant
A kit comprising a first container containing a Rhipicephalus microplus immunogen as defined above, instructions for administering the immunogen to an ungulate, and optionally a second container with a pharmaceutically acceptable carrier, and optionally a third container with an adjuvant.
Composition comprising RmAQP2 immunogen and adjuvant
A composition comprising a R. microplus immunogen comprising amino acid sequences selected from SEQ ID NO: 2, SEQ ID NO: 5, SEQ ID NO: 7, SEQ ID NO: 9, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, and SEQ ID NO: 27, combined with an adjuvant as described above.
Immunogenic composition with RmAQP2 peptides conjugated to a carrier
An immunogenic composition comprising a pharmaceutically acceptable carrier and RmAQP2 peptide(s) selected from SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID NO: 27, and their combinations, where each peptide is conjugated to a carrier such as bovine serum albumin, keyhole limpet hemocyanin, ovalbumin, or polylysine.
The claims encompass compositions and kits comprising RmAQP2 proteins or peptides and pharmaceutically acceptable carriers and adjuvants designed to elicit an immune response in ungulates. They cover various antigen forms including peptides and proteins, conjugated peptides, and compositions with defined carriers and adjuvants, providing tools for immunizing animals against ticks and reducing tick-borne diseases.
Stated Advantages
Administration of RmAQP2 or its fragments to ungulates reduces reproductive viability of R. microplus ticks, thereby decreasing egg mass, hatching success, and larval survival.
Reduced tick reproduction leads to lowered tick infestations in treated animals, contributing to decreased incidence of tick-borne pathogens such as Babesia bovis.
Immunogenic compositions targeting RmAQP2 provide an alternative or complement to acaricides and existing vaccines, potentially overcoming issues of resistance and inconsistent vaccine efficacy.
Documented Applications
Use of immunogenic compositions containing RmAQP2 or specific peptides to induce immune responses in ungulates, reducing tick infestation and reproduction.
Vaccination of cattle and other ungulates to protect against bovine babesiosis and other diseases transmitted by R. microplus.
Production of genetically altered organisms expressing RmAQP2 for use in immunization or as part of vaccine compositions.
Kits containing RmAQP2 immunogens, carriers, and adjuvants for preparing and administering tick-protective vaccinations to cattle and other ruminants.
Interested in licensing this patent?