Figure 5. Incubation of anti-GM1 Ab pretreated GD3s^–/– NMJs in Ringer’s solution for 1 hour at 37°C before addition of NHS attenuates complement-mediated pathophysiological effects.

(A) NMJs incubated for 1 hour at 37°C in Ringer’s medium (to facilitate Ab endocytosis) exhibited a lower increase in MEPP frequency following the addition of NHS as a complement source, compared with positive pathological controls pretreated with anti-GM1 Ab, then directly exposed to NHS (i.e., without an Ab endocytosis step). (B) Typical examples of MEPP recordings under pathological control conditions in comparison with 1 hour of Ab uptake prior to exposure to NHS. One-second trace. (C) The lower MEPP frequency in the 1-hour 37°C Ringer’s medium–incubated muscles was accompanied by less intense muscle fiber twitching.