Anti-nuclear antibody detection and diagnostics for systemic and non-systemic autoimmune disorders
Provided are compositions that contain mammalian cells for use in detecting antibodies. The mammalian cells are modified such that they do not contain LEDGF protein. The mammalian cells are immobilized on a solid substrate. The compositions can also contain mammalian cells that contain the LEDGF protein. Methods for using the cell compositions in diagnostic approaches are included, as are kits for performing diagnostic tests.
1. An in vitro composition comprising Hep-2 cells immobilized on a solid substrate, comprising: Hep-2 cells comprising a modification genomic DNA that reduces the expression of lens epithelium derived growth factor (LEDGF) protein; and
non-genomically modified Hep-2 cells comprising the LEDGF protein, wherein the composition comprises from about 50% to about 95% genomically modified cells.
2. The in vitro composition of claim 1 , wherein the Hep-2 cells are killed and permeabilized.
3. The in vitro composition of claim 1 , wherein said LEDGF protein is present in a complex with a primary antibody which binds to LEDGF protein.
4. The in vitro composition of claim 3 , wherein the genomically modified Hep-2 cells comprise a chromosome comprising the nucleic acid sequence of SEQ ID NO: 14.
5. The in vitro composition of claim 1 , wherein the composition comprises about 85% to about 95% genomically modified cells.
6. The in vitro composition of claim 1 , wherein the modification to genomic DNA comprises a gene encoding a detectable protein which has replaced the gene encoding the LEDGF protein (PSIP1 gene).
7. The in vitro composition of claim 1 , further comprising:
auto-antigens to which anti-nuclear autoantibodies bind; and
anti-human secondary antibodies that bind to the anti-nuclear autoantibodies.
8. The in vitro composition of claim 1 , wherein the genomically modified Hep-2 cells do not express a detectable amount of LEDGF.