To determine an efficient expression strategy in Arabidopsis thaliana and to determine whether a dimeric oleosin fusion approach could achieve keratinocyte growth factor-2 (KGF2) expression and bioactivity. Higher recombinant protein accumulation was observed in the two dimeric oleosin constructs than in a single-oleosin-fused protein (O::KGR2) or KGF2 control. Highest expression was in O-O::KGF2-transgenic seeds. MTT assay in FGFR2 III b-BaF3 cells revealed comparable levels of bioactivity due to O-O::KGF2 and O::KGR2, whereas O::KGF2-O had no effect on FGFR2 III b-BaF3 opithelial cell growth. The transgenic proteins had a pronounced stimulatory effect on hair follicle proliferation in C57BL/6 mice. A dimeric oleosin approach can be used to express KGF2 with the non-symmetrical O-O::KGF2 construct showing the highest expression and bioactivity.