Figure 3

Stimulated saliva and tear flow in treated C57BL/6.NOD- Aec1Aec2 mice. Saliva and tear flow were collected as described in the Materials & Methods section. The data shown represent the mean ± SEM flow per group (n = 6 in AAV2-LacZ group and n = 7 in AAV2-CTLA4IgG group). Unpaired student t-test was used in this analysis. (A) Mice treated with vector expressing CTLA4IgG showed protection from loss of gland activity. Saliva was collected over a 10-min period after stimulation with a 100 μl of PBS containing a mixture of isoproterenol (0.02 mg/ml) and pilocarpine (0.05 mg/ml) and tear flow were collected over a 20-s period after injection of pilocarpine (4.5mg/kg body weight). AAV2-LacZ mice showed decreased saliva on weeks 16, 22, 26, and 30 (asterisk, P = 0.0428, 0.0217, 0.0292, and 0.0128, respectively), compared with the baseline saliva collection on week 6 (n = 9, 5.933 ± 0.2969). AAV2-CTLA4IgG-treated mice had a slight decrease of saliva but this was not significant at 16 weeks (P = 0.2057). Saliva flow of CTLA4IgG-treated mice increased to baseline level by 22 weeks (6.13 ± 0.92 μL/g 10 min). CTLA4IgG-treated mice had increased saliva flow compared with LacZ-treated mice by 30 weeks (P = 0.0232). (B) Delivery of AAV2-CTLA4IgG resulted in an increase in tear flow (mean ± SEM) by 30 weeks compared with control mice, but this was not significant (P = 0.1316).