Figure 5

Increased recruitment of Mpx-positive neutrophils at the onset of regeneration after multiple cryoinjuries. (A) Cross sections of adult zebrafish hearts immunostained for L-plastin (green) and Myeloperoxydase (Mpx, red) at 4 dpci following one, two three and six cryoinjuries (CIs). The cardiac muscle is detected by F-actin staining (Phalloidin, blue). Both L-plastin and Mpx were detected in the wound. L-plastin/Mpx double positive cells are indicated (white arrow). The dashed line encircles the post-injury zone. Scale bars = 100 µm. (B) Analysis of the percentage of L-plastin-positive area within the wound. No significant change (NS) is observed between the experimental groups. N ≥ 3. Scatter plot of the data with a large bar indicating the mean and smaller bars representing the SEM. (C) Analysis of the percentage of Mpx-positive area in the wound. Multiple cryoinjuries significantly increase the number of neutrophils compared to specimens after one cryoinjury. N ≥ 3; *P < 0.05. Scatter plot of the data with a large bar indicating the mean and smaller bars representing the SEM.