Detection method for human pappilomavirus (HPV) and its application in cervical cancer
Embodiments of the invention provide methods, assays, and kits for detecting HPV infection and HPV associated epithelial cell abnormalities, most notably those associated with pre-malignant and malignant epithelial cell lesions. Detection of HPV DNAs, genomes, and/or oncoproteins by nucleic acid hybridization assays and immunological assays can be used in early clinical screening for HPV infection and diagnosis for cervical cancer. The polypeptides, recombinant proteins, antibodies, nucleic acids, and various detection methods thereof are particularly useful for diagnosing carcinomas of the uterine cervix and those at risk of developing cervical cancer.
1. A method of making a composition comprising a recombinant HPV protein selected from the group consisting of a papillomavirus E6 gene product, a papillomavirus E7 gene product, a papillomavirus L1 gene product, and a papillomavirus L2 gene product, comprising the steps of:
providing a recombinant construct encoding a fusion protein comprising said papillomavirus gene product and an affinity tag selected from the group consisting of a HIS tag, a GST tag, and an MBP tag, wherein said construct does not encode a chaperone;
expressing said recombinant construct in a host cell;
incubating an extract prepared from said host cell with an affinity resin under conditions in which said affinity resin specifically binds said affinity tag; and
eluting said recombinant HPV protein from said affinity resin, wherein said expressing of said recombinant construct in said host cell results in a level of protein expression such that said eluting produces a composition comprising said recombinant HPV protein at a concentration of from 1 mg/L to 10 mg/L, wherein said recombinant HPV protein is present in said composition at a purity of at least 90% as determined by SDS PAGE, and wherein said recombinant HPV protein is present in said composition in a substantially soluble, monomeric form, as determined by size-exclusion chromatography.
2. The method of claim 1 , wherein said recombinant HPV protein is present in said composition in a native conformation.
3. The method of claim 1 , wherein said recombinant protein is capable of specifically binding to an antibody present in a sample obtained from a mammalian subject infected by a papillomavirus encoding said E6 gene product, said E7 gene product, said L1 gene product, or said L2 gene product.
4. The method of claim 1 , wherein said papillomavirus is selected from the group consisting of HPV-6, HPV-11, HPV-16, HPV-18, HPV-31, HPV-33, HPV-35, HPV-39 , HPV-42, HPV-43, HPV-44, HPV-45, HPV-51, HPV-52, HPV-53, HPV-54, HPV-55, HPV-56 , HPV-58, HPV-59, and HPV-66.
5. A method for assessing risk for developing cervical cancer in a human subject, comprising:
obtaining a sample from said subject, said sample comprising antibodies produced by said subject;
contacting said sample with one or more recombinant HPV proteins selected from the group consisting of a papillomavirus E6 gene product, a papillomavirus E7 gene product, a papillomavirus L1 gene product, and a papillomavirus L2 gene product, wherein each of said one or more recombinant HPV proteins is isolated according to the method of claim 1 , and wherein each of said one or more recombinant HPV proteins is capable of specific binding to an antibody produced by a human infected with a papillomavirus encoding said E6, E7, L1, or L2 gene product, wherein said contacting takes place under conditions that permit the specific binding of said antibody to said one or more recombinant HPV proteins;
determining the presence, absence, or amount of one or more antibodies in said sample that specifically binds to said one or more recombinant HPV; and
assessing the risk for developing cervical cancer in said subject based on the determined presence, absence, or amount of said one or more antibodies in said sample.
6. The method of claim 5 , wherein said papillomavirus is selected from the group consisting of HPV-6, HPV-11, HPV-16, HPV-18, HPV-31, HPV-33, HPV-35, HPV-39, HPV-42, HPV-43, HPV-44, HPV-45, HPV-51, HPV-52, HPV-53, HPV-54, HPV-55, HPV-56, HPV-58, HPV-59, and HPV-66.