Abstract
Purpose: :
To determine the effects of breeding source of mice, sex of mice, dosing regimen and laser operator on the area of CNV induced by laser burns.
Methods: :
We reviewed the mean area of CNV from the control groups of 143 mouse laser-induced CNV studies.The laser CNV assays were all run in a standard format. Eyes from C57BL/6 mice were lasered with an Iridex Oculight® GLx 532nm laser, 3 lesions/eye, 6 lesions/mouse, n =10 mice/cohort yielding 60 data points per cohort. Mice were injected iv with vascular label and sacrificed 7 days after laser. CNV lesions were captured by fluorescent microscopy and lesion area analyzed with Axiovision software. Data was masked during image acquisition, application of exclusion criteria and data analysis. All mice in a cohort were age and sex matched from a single vendor. Inter-group differences were analyzed by one-way analysis of variance (ANOVA) with a Neuman-Keuls post hoc analysis or an unpaired two tailed t test. Mice were either treatment naive or dosed by oral gavage, topical drop or by IP injection.
Results: :
The average CNV area of cohorts of mice in mm2 x10-6 ± SD were 21.7 ± 5.7 for mice from Taconic (n= 93), 18.9 ± 4.9 (n= 3) for mice from Novartis, 11.6 ± 3.5 for mice from Charle’s River (n= 34) and 7.5 ± 1.4 for mice from Jackson (n = 10). The area differences between groups were all statistically significant except for the area difference between Novartis and Taconic mice.Male mice have a non-significant trend to smaller CNV compared to female mice (p> 0.05). For example, the average CNV area in mm2 x10-6 ± SD were; Jackson female 8.4 ± 0.7 (n =3), male area CNV = 7.0 ± 1.4 (n = 7), Taconic Female 21.7 ± 5.8 (n = 85), male 18.5 ± 4.0 (n = 8).The CNV area was not significantly changed by the dosing regimen (p>0.05). The average CNV area in mm2 x10-6 ± SD were; Taconic mice orally dosed 22.4 ± 5.7, topically dosed 22.5 ± 5.9, IP dosed 20.9 ± 6.4 and naive 19.4 ± 4.6, Charles River orally dosed 11.2 ± 2.4 and topically dosed 11.3 ± 3.7. (n = 10 to 39 cohorts per group)No significant differences in CNV area were observed between 4 independent laser operators in the Taconic mice cohorts. Average area of CNV per operator ranged from 19.0 ± 4.8 to 22.3 ± 6.1 mm2 x10-6 ± SD, (p>0.05, n = 8 to 41 cohorts/operator).
Conclusions: :
The breeding facility of origin of mice has a significant effect on the area of CNV induced by laser. In our experience, laser operator and dosing regimen are not critical factors in determining CNV area.
Keywords: choroid: neovascularization • laser