Matrix metalloproteinase 2 improves the transplanted adipocyte survival in mice.

BACKGROUND: Fat tissue is a common material for autologous transplantation in plastic and reconstructive surgery. Basic fibroblast growth factor (bFGF) ameliorates the fat graft survival. A transplantation model has shown the gene expression of matrix metalloproteinases (MMPs) to increase in adipocytes. The aim of this study is to investigate the role of MMPs in the amelioration of survival by bFGF. MATERIALS AND METHODS: 3T3-L1 adipocytes were incubated with or without 10 microg mL(-1) bFGF for 8 h in the presence or absence of the MMP inhibitor GM6001, vascular endothelial growth factor (VEGF), MMP-2 or anti-bFGF antibody to study the effect of bFGF on MMP-2 mRNA expression, MMP-2 activity, fat accumulation or 2-deoxyglucose uptake. Collagen sheets containing l x l0(7) adipocytes with or without bFGF in the presence or absence of GM6001 were subcutaneously transplanted into mice, and the appearance, histology, mRNA expression and fat accumulation of the grafts were analysed 4 weeks after transplantation. RESULTS: The MMP-2 expression was drastically induced by bFGF among MMPs in 3T3-L1 adipocytes. MMP-2 accelerated fat accumulation, peroxisome proliferator-activated receptor gamma (PPAR gamma) mRNA expression, and glucose uptake to an extent similar to those induced by bFGF, respectively. The bFGF-induced increases were inhibited by the blocking of MMP-2. The transplantation of adipocytes into mice showed that bFGF ameliorates the appearance and fat accumulation, as well as mRNA expression in grafts. These effects were almost or partly inhibited by a MMP blockade. CONCLUSIONS: MMP-2 may be involved in the mechanism by which bFGF ameliorates the survival of fat grafts.

Establishment of gene-vaccinated skin grafting against Toxoplasma gondii infection in mice.

Vaccine effects of in vivo gene-vaccinated skin graft were evaluated against Toxoplasma gondii (T. gondii) infection. By using a gene gun, cDNA coding T. gondii SAG1 molecule was intracutaneously vaccinated into C57BL/6 (B6; a susceptible strain), BALB/c (a resistant strain) and (C57BL/6 x BALB/c) F1 (CBF1) mice, and the gene-vaccinated skin of these strains was transplanted to CBF1 mice. Regarding the antibody production against SAG1, CBF1-recipient mice transplanted with the SAG1 gene-vaccinated B6 skin were high responders, whereas CBF1 mice skin grafted with vaccinated skin of both BALB/c and CBF1 mice were low responders. The donor-derived LC/DC migrated to the draining lymph nodes of the recipients from the skin graft within 3 days. The vaccine effect against T. gondii challenge infection was obtained in CBF1 mice which received the skin graft of the SAG1 gene-vaccinated BALB/c mice.

Establishment of a parabiotic rat model by anastomosis of common carotid artery.

A cross circulation model was established by replacing mutual blood between two rats by anastomoses of each common carotid artery. In this model, parabiotic rats were shown to replace their mutual blood completely without any artificial materials or instruments, such as silicon tubes or pumps. The rate of blood exchange was measured by intravenous injection of Evans blue dye without the use of the radioactive materials that were so far commonly used. The partial alteration of blood circulation through microvascular surgery may reveal the mechanisms of organ tropism of bacteria, protozoa, and parasites. Microvascular surgery is available for reconstruction and analysis of organ functions as well as for clinical use in organplasty.