The objective of this study is to investigate the characteristics of the recombinant variant ofhuman vascular endothelial cell growth inhibitor,VEGI_(72-251),and compare its biological activities with that ofits prototype VEGI_(24-174),The recombinant plasmid containing the variant VEGI_(72-251) gene was constructedand expressed in Escherichia coli.The effects of the expressed VEGI_(72-251) on cell proliferations were checkedin the human umbilical vein endothelial cell line and certain tumor cell lines (ECV304 and B 16).The inhibitionof VEGI_(72-251) on angiogenesis was detected in the chorioallantoic membrane of chick embryos.In comparisonwith VEGI_(24-174),the recombinant human VEGI_(72-251) seems to have no effect on the proliferation of endothelialcells and the angiogenesis of the chorioallantoic membrane in vitro.An enzyme-linked immunosorbent assay-based method was used for the measurement of interleukin-2 (IL-2) production by peripheral blood monocytes(PBMCs) treated with VEGI_(72-251).PBMCs were pretreated with VEGI_(72-251) (1.25-12.50μg/ml) for 24 h invitro,and the IL-2 concentration in PBMC medium was increased from 354 pg/ml to 1256 pg/ml.It can beconcluded that VEGI_(72-251) is able to increase the level of human IL-2 production by the activation of Tlymphocytes.Differing from VEGI_(24-174) on anti-angiogenesis,VEGI_(72-251) may serve as an anti-cancer factorthrough its activation of T lymphocytes. The objective of this study is to investigate the characteristics of the recombinant variant of human vascular endothelial cell growth inhibitor, VEGI_ (72-251), and compare its biological activities with that of prototypes VEGI_ (24-174), The recombinant plasmid containing the variant The VEGI_ (72-251) gene was constructed and expressed in Escherichia coli. These effects of the expressed VEGI_ (72-251) on cell proliferation were detected in the human umbilical vein endothelial cell line and certain tumor cell lines (ECV 304 and B 16) inhibitionof VEGI_ (72-251) on angiogenesis was detected in the chorioallantoic membrane of chick embryos.In comparison with VEGI_ (24-174), the recombinant human VEGI_ (72-251) seems to have no effect on the proliferation of endothelial cells and the angiogenesis of the chorioallantoic membrane in vitro. An enzyme-linked immunosorbent assay-based method was used for the measurement of interleukin-2 (IL-2) production by peripheral blood monocytes (PBMCs) treated with VEGI_ 72-251). PBMCs were pretreated with VEGI_ (72-251) (1.25-12.50 μg / ml) for 24 h invitro, and the IL-2 concentration in PBMC medium was increased from 354 pg / ml to 1256 pg / ml. It can beconluded that VEGI_ (72-251) is able to increase the level of human IL-2 production by the activation of Tlymphocytes. Differing from VEGI_ (24-174) on anti-angiogenesis, VEGI_ (72-251) may serve as an anti-cancer factorthrough its activation of T lymphocytes.