Fig. 4

zT_reg Cells Are Required for Organ Regeneration

(A) Spinal cord sections from control (left) and zT_reg cell-ablated fish (right).

(B) Retrograde tracing of axonal projections using Fluoro-Ruby (FR). Regenerating axons spanned the transection injury in control fish (left; 6/6) but not zT_reg cell-depleted fish (right; 1/6; p < 0.05).

(C) Quantification of regeneration in (A) (n = 6–8).

(D) Swim tracking of individual animals after spinal cord injury.

(E) Quantification of total distance moved in (D) (mean ± SEM, n = 8–14).

(F) Picro-Mallory staining of heart sections from control (left) and zT_reg cell-ablated fish (right).

(G) Quantification of regeneration in (F) (n = 7–10).

(H) Quantification of scar tissue size (left) and myocardial wall thickness (right) in (F) (mean ± SEM, n = 10).

(I) Luxol fast blue staining of retina sections from control (left) and zT_reg cell-ablated fish (right).

(J) Quantification of regeneration in (I) (n = 8).

Asterisks indicate injury epicenter. Mtz, metronidazole; TG, foxp3a:NTR; Veh, vehicle; WT, wild-type. Confocal projections of z stacks are shown, except for the images in (F) and (I). NS, not significant; ^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗∗p < 0.001, Fisher's exact test (B, C, G, and J), unpaired two-tailed Student's t test with Welch correction (E), and Mann-Whitney U test (H). Scale bars, 50 μm (A, B, F, I) and 0.1 m (D). See also Figure S1.