Familial dysautonomia (FD) is caused by a single base change in the Ikbkap gene that results in a deficit of Ikbkap protein in neurons. As such, FD is a good candidate for gene-based treatment to prevent blindness and possibly other manifestations of the disease. American Gene Technologies™ (AGT) is collaborating on FD with Dr. Frances Lefcort, Chair of the Department of Cell Biology and Neuroscience at Montana State University, who has two mouse models of FD. With a grant of only $37,000 from the FD Foundation, AGT was able to develop several FD gene therapy vectors that express Ikbkap at physiological levels and in the correct subcellular locations. Using these vectors, Dr. Lefcort demonstrated that neurons derived from her FD mice, which normally die in cell culture within two to three days, were robust and healthy after three days when treated with AGT’s gene therapy vectors (see figure below). These are the first positive results that the FD Foundation has ever seen in progressing toward an efficacious treatment of FD.
AG-IKAP: Familial Dysautonomia therapeutic lentivirus
Rescue of post-mitotic neuronal cell death by treatment with AG-IKAP
Neurons in cultured dorsal root ganglion (DRG) isolated from Ikbkap-/- conditional knockout mice die within three days. In collaboration with Dr. Frances Lefcort, we tested if AG-IKAP can rescue Ikbkap-/- neurons from cell death.
DRG neurons were isolated from day E17.5 Wnt1-Cre;IkbkapLoxP/LoxP embryos and infected with either AG-IKAP-GFP or control AG-GFP virus. After two days in culture, cells were visualized by immunofluorescence to detect GFP (green) and neurons stained with Tuj-1 (red).
While both AG-IKAP-GFP and control AG-GFP infect neurons and Schwann cells, only the therapeutic virus expressing IKAP was able to rescue the Ikbkap-/- neurons from cell death.
This work was supported by a grant from the Dysautonomia Foundation. Future experiments will validate the ability of AG-IKAP to rescue neurons in vivo in mouse models of FD.
On August 10, 2015, AGT received an NIH Grant of $230,000 to further Familial Dysautonomia research.