In line with this, Onoe et al. demonstrated that HPE-type HSP of CD4+ T cells correlated with the percentage of CD14+ monocytes in the periphery when autologous T cells reconstituted in BLT mice were adoptively transferred into T cell-deficient humanized NOD/SCID mice and suggested that CD4+ T cells need to interact with self MHC-II molecules expressed by autologous myeloid-derived antigen-presenting cells (APCs) to drive their expansion [26]. This evidence concerns the gene CD4 and hereditary spastic paraplegia.