摘要 |
<p>Methods and compositions for modulating protein function in a cell involving intracellular expression of an antibody homologue that binds to the protein within the cell are disclosed. In a preferred embodiment, an antibody homologue, such as a single chain Fv (sFv) fragment, is expressed within an intracellular compartment of a cell, such as the endoplasmic reticulum (ER), to inhibit cell surface expression of a membrane protein. Preferably, the cell is a malignant mammalian cell and the protein is a cell surface receptor oncoprotein, such as c-erbB2. Intracellular binding of the antibody homologue to the receptor oncoprotein inhibits its surface expression and, moreover, inhibits cell proliferation and cell survival. Isolated nucleic acid molecules encoding anti-c-erbB2 antibody homologues, as well as recombinant expression vectors and host cells incorporating these nucleic acid molecules, are also disclosed.</p> |