Figure 1. SDF-1α mRNA expression in corneas after alkali injury. A: Semi-quantitative RT–PCR to evaluate mRNA expression of SDF-1α. Corneas were harvested at the indicated time points, and five corneas at each time point were pooled to extract total RNAs. RT–PCR was performed using the obtained total RNAs. B: The ratios of SDF-1α to Actb mRNA were determined. All values represent mean±SEM of three to five independent measurements.