[The construction of recombinant type I herpes simplex virus carrying GALV.fus gene and its antitumor effect in nude mice].

OBJECTIVE: To observe the killing effect of recombinant type I herpes simplex virus (HSV-I) with Gibbon ape leukemia virus membrane fusion glycoprotein (GALV.fus) gene on lung adenocarcinoma in vitro and in vivo.

METHODS: Recombinant HSV-I plasmids (HSV-UL38P-GALV.fus, HSV-CMVP-GALV.fus, HSV-CMVP-EGFP) was introduced into green monkey kidney cells (Vero) by liposome to amplify the virus, which were propagated in Vero cells and purified by cesium chloride density purification, titrated by TCID50 method. The three recombinant viruses were named as Synco-2, Synco-1 and Baco-1 respectively, and were transfected into lung adenocarcinoma cell line A549 cell and human lung adenocarcinoma xenografts which were established in nude mice subcutaneously to observe the expression and transfection of recombinant plasmids; mice model was divided to A (Control) group, B (Baco-1) group, C (Synco-1) group, D (Synco-2) group and E (Synco-2) group. The antitumor and cytotoxic effects of the virus in vitro or in vivo were investigated simultaneously.

RESULTS: Recombinated HSV-I virus were packed successfully, the titre of Baco-1, Synco-1 and Synco-2 were 3 x 10(10) pfu/mL, 1X 10(11) pfu/mL and 4 x 10(10) pfu/mL respectively. The virus produced clear antitumor effects in vitro, the oncolytic activity of Synco-2 and Synco-1 was superior to that of Baco-1 (P < 0.01). The striking antitumor effect was seen when the virus was given subcutaneously in established xenografts in the animals. Tumor volume in Group C and D decreased significantly compared those in Group A and B (P < 0.01). The same result was observed in tumour weight (P < 0.01), and we also find that there was statistical significance between Group C and D in tumour quality at last two weeks (P < 0.01).

CONCLUSIONS: The three recombinant HSV-I were packaged, amplificated and purified successfully. Recombinant GALV. fus gene system controlled by special promoter and mediated by available carrier has potent activity against lung cancer both in vitro or in vivo, and maybe a new promising candidate for investigative gene therapy of this malignancy.