  We report low-temperature transport measurements in strained
InAs/Ga0.68In0.32Sb quantum wells, which supports time-reversal
symmetry-protected helical edge states. The temperature and bias voltage
dependence of the helical edge conductance for devices of various sizes are
consistent with the theoretical expectation of a weakly interacting helical
edge state. Moreover, we found that the magnetoresistance of the helical edge
states is related to the edge interaction effect and the disorder strength.
