The various vectors were injected (intra-articular, 50 µl per ankle) 14 days after arthritis induction, defined as day 0. The first animal experiment was designed to assess short-term efficacy and to determine the best dose of vector. Thirty rats were divided into six groups (n = 5 per group). Three control groups were recombinant baculovirus alone (BVCAR; 105 PFU per joint), adenovirus vector harbouring the PUMA gene alone (HAdV5-PUMA; 109 PFU per joint), and BVCAR (105 PFU per joint) in combination with an empty adenoviral vector (HAdV5-null; 109 PFU per joint). The three therapeutic groups associated BVCAR (105 PFU per joint) with HAdV5-PUMA at three concentrations (107, 108 and 109 PFU per joint, respectively). In this experiment, the animals were euthanized on day 4 post-intra-articular injection.