Figure 5

Antibody deficiency ameliorates myelin degeneration in P0het mutants. (A) Representative ultrathin sections of femoral quadriceps nerves from 6-month-old wildtype (P0wt JHD+/+), single (P0het JHD+/+), and double mutants (P0het JHD−/−). Asterisks indicate abnormally myelinated fibers and arrows supernumerary Schwann cells (‘onion bulbs’). Scale bar, 5 μm. (B, C) Quantification of abnormally myelinated fibers (B) and onion bulbs (C) demonstrate signs of significant amelioration of demyelination and improved myelin integrity in P0het JHD−/− double mutants in comparison to P0het JHD+/+ mice (n = 4 to 5). Kruskal-Wallis test with Bonferroni-Holm correction, # (significant difference to P0wt), * (significant difference between P0het mutant groups). #, *P < 0.05. n.d. (not detected). (D) Quantification of the g-ratio (axon diameter/fiber diameter) demonstrates a significant increase in myelin thickness in P0het JHD−/− compared to P0het JHD+/+ mice (n = 4, 125 to 135 axons per animal). Two-tailed Student’s t-test. *P < 0.05.