Importantly, overexpression of either of the spastin isoforms led to a reduction in neurite swellings and the restoration of the number of primary neurites, neurite length and branching points in SPG4 neuronal cultures [multiplicity of infection (MOI): 0.25–0.5, P ≤ 0.05 for all analyses, Figure 6A–D]. Here, SPAST is linked to infection.