The in vitro transduction efficiency of AAV2-CDNF was determined by applying the virus

particles to HeLa cells that were then stained by anti-CDNF antibody to verify CDNF expression. The expression of all recombinant proteins was driven by the CMV promoter. Figure 1 Schematic drawing of the pAAV2-CDNF vector (A) and experimental design for evaluating the neuroprotective effect of AAV2-CDNF in a 6-OHDA partial lesion model of PD in rats (B). Animals and surgery Animals Wistar male rats (Harlan, the Netherlands) were group-housed under standard laboratory conditions in a 12 h/12 h dark/light cycle with free access to rodent food and Inhibitors,research,lifescience,medical fresh tap water. All animal procedures were reviewed and approved by the National Animal Experiment Board (ESLH-2009-05234 Ym-23) and carried out in accordance with Inhibitors,research,lifescience,medical the European Communities Council Directive 86/609/EEC. AAV2 vector injection Rats (250–300 g) were anesthetized with isoflurane

(4% induction, 2.5–3.0% maintenance) and the recombinant AAV2 viral vectors were injected into the rat striatum in a stereotaxic operation. To target the striatum, viral vectors were given as single injections into the left hemisphere, 1.0 mm anterior and Inhibitors,research,lifescience,medical 2.7 mm lateral to bregma, and 5.0 mm below the dura (stereotaxic coordinates according to Paxinos and Watson 1997). For behavioral experiments and analysis of cell survival after lesioning, rats were randomly divided into six treatment groups (n = 9–10/group) receiving three different doses of AAV2-CDNF (4.0 × 107, 2.0 × 108, 1.0 × 109 vg/striatum), AAV2-GDNF (1.0 × 109 vg/striatum), or one of the two negative controls (AAV2-GFP 2.0 × 108 vg/striatum or PBS). For analysis of protein expression, Inhibitors,research,lifescience,medical rats were injected with AAV2-CDNF 4.0 × Inhibitors,research,lifescience,medical 107 (n = 4), 2.0 × 108 (n = 4), or 1.0 × 109 vg

(n = 20), or AAV2-GDNF 1.0 × 109 vg (n = 3) into the left striatum. The right striatum was left intact, or injected with AAV2-GFP or PBS. Injections were done using a stereotaxic injector (Stoelting, Wood Dale, IL) and 10-μL syringes (Hamilton, Bonaduz, Switzerland). Injection volume was set to 5 μL (AAV2 viral stocks were, if necessary, diluted with PBS) and injection speed was 1 μL/min, leaving the needle in place for of 2 min before withdrawal. Rats received EPO906 tramadol 1 mg/kg subcutaneously (s.c.) for postoperative pain and were kept in single cages overnight. Lesions For all rats in the neuroprotection study, lesioning of the midbrain DAergic system was done 2 weeks after viral vector injections using 6-OHDA (6-OHDA hydrochloride; Sigma, St. Louis, MO) (Fig. 1B). Thirty minutes before the 6-OHDA injections, rats received desipramine 15 mg/kg intraperitoneally (i.p.) (desipramine hydrochloride, Sigma) to protect noradrenergic nerve terminals from the toxin. 6-OHDA was injected under isoflurane anesthesia using stereotaxis as described above. Rat received two injections, each 10 μg of 6-OHDA (2.