The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 26, 1986
Filed:
Oct. 25, 1983
George H Yoakum, Gaithersburg, MD (US);
Curtis C Harris, Bethesda, MD (US);
Brent E Korba, Laurel, MD (US);
John F Lechner, Wheaton, MD (US);
Other;
Abstract
A modified protoplast fusion method and cell line is disclosed that stably transfects human cells with pSV2-derived plasmids at frequencies greater than 10.sup.-3. This procedure makes it possible to test the biological effect of individual genes (i.e., oncogenes and other cellular genes, and viral genes). To demonstrate the utility of this invention, a pSV2gpt.sup.+ plasmid constructed to carry a subgenomic fragment of hepatitis B virus (HBV) that contained the core antigen gene (HBc gene) is transfected into human cells. Human cell lines are stably transfected with the HBC.sup.+ gene by selecting recipient cells for expression of guanine phosphoribosyl transferase expression; other selective markers, i.e., neomycin resistance, can also be used. Conditions for enhancing the expression of the transfected gene(s) have also been developed. For example, with this gpt.sup.+ /HBc.sup.+ cell line it is shown that growth in serum-free medium or treatment with 5'-azacytidine stimulates the production of the HBV core antigen.