No abstract

Aldehyde dehydrogenase 2 (ALDH2) deficiency causes “Asian flush syndrome,” presenting as alcohol-induced facial flushing, tachycardia, nausea, and headaches. One of the most common hereditary enzyme deficiencies, it affects 35%–40% of East Asians and 8% of the world population. ALDH2 is the key enzyme in ethanol metabolism; with ethanol challenge, the common ALDH2*2 (E487K) mutation results in accumulation of toxic acetaldehyde. ALDH2*2 heterozygotes have increased risk for upper digestive tract cancers, compounded by smoking and drinking alcohol. We hypothesized that a one-time administration of an adeno-associated virus (AAV) gene transfer vector expressing the human ALDH2 coding sequence (AAVrh.10hALDH2) would correct the deficiency state. AAVrh.10hALDH2 was administered intravenously to Aldh2 knockout (Aldh2−/−) and Aldh2 E487K knockin homozygous (Aldh2E487K+/+) mice. Following acute ethanol ingestion, untreated ALDH2-deficient mice had elevated acetaldehyde levels and performed poorly in behavioral tests. In contrast, treated Aldh2−/− and Aldh2E487K+/+ mice had lower serum acetaldehyde levels and improved behavior. Thus, in vivo AAV-mediated ALDH2 therapy may reverse the deficiency state in ALDH2*2 individuals, eliminating the Asian flush syndrome and reducing the risk for associated disorders.

The median survival of glioblastoma multiforme (GBM) approximately 1 yr. Following surgical removal, systemic therapies are limited by the blood-brain barrier. To circumvent this, we developed a method to modify neurons with the genetic sequence for therapeutic monoclonal antibodies using adeno-associated virus (AAV) gene transfer vectors, directing persistent, local expression in the tumor milieu. The human U87MG GBM cell line or patient-derived early passage GBM cells were administered to the striatum of NOD/SCID immunodeficient mice.AAVrh.10BevMab, an AAVrh.10-based vector coding for bevacizumab (Avastin ® ), an antihuman vascular endothelial growth factor (VEGF) monoclonal antibody, was delivered to the area of the GBM xenograft. Localized expression of bevacizumab was demonstrated by quantitative PCR, ELISA and Western. Immunohistochemistry showed the bevacizumab was expressed in neurons. Concurrent administration of AAVrh.10BevMab with the U87MG tumor reduced tumor blood vessel density, and tumor volume and increased survival. Administration of AAVrh. 10BevMab 1 wk after U87MG xenograft reduced growth and increased survival. Studies with patient-derived early passage GBM primary cells showed a reduction in primary tumor burden with an increased survival. This data supports the strategy of AAV-mediated CNS gene therapy to treat GBM, overcoming the blood-brain barrier through local, persistent delivery of an antiangiogenesis monoclonal antibody.

No abstract

We are investigating canine distemper virus (CDV) as a vaccine vector for the delivery of HIV envelope (Env) that closely resembles the native trimeric spike. We selected CDV because it will promote vaccine delivery to lymphoid tissues, and because human exposure is infrequent, reducing potential effects of pre-existing immunity. Using SIV Env as a model, we tested a number of vector and gene insert designs. Vectors containing a gene inserted between the CDV H and L genes, which encoded Env lacking most of its cytoplasmic tail, propagated efficiently in Vero cells, expressed the immunogen on the cell surface, and incorporated the SIV glycoprotein into progeny virus particles. When ferrets were vaccinated intranasally, there were no signs of distress, vector replication was observed in the gut-associated lymphoid tissues, and the animals produced anti-SIV Env antibodies. These data show that live CDV-SIV Env vectors can safely induce anti-Env immune responses following intranasal vaccination.