Immunoregulatory and antitumor effects of interferon-γ

IFN-y was one of the first cytokines produced by recombinant DNA technology. After the production of recombinant DNA derived mouse and human IFN-y, recombinant DNA derived rat IFN-y became available. With this species-specific cytokine it has become possible to study biological effects of IFN-y in rats. Compared to the mouse model, the rat model is more suitable to study activities of IFN-y in tumor and organ transplantation experiments, since these experiments are technically far less demand

Surgical learning curve in kidney transplantation: A systematic review and meta-analysis

Aim: To assess the impact of the learning curve of kidney transplantation on operative and postoperative complications. Methods: A literature search was systematically conducted to evaluate the significance of the learning curve on complications in kidney transplantation. Meta-analyses of the effect of the learning curve on warm ischemic time, total operating time (TOT), vascular and urological complications, postoperative bleeding, lymphocele and infection. Results: Nine studies met the inclusion criteria and 2762 patients were included in the present meta-analyses. Surgeons at the beginning of the learning curve were found to have longer TOT (mean difference 41.77 (95% CI: 4.48–79.06; P = .03) and more urological complications (risk ratio 3.93; 95% CI: 1.87–8.25; P < .01). No differences were seen in warm ischemic time, postoperative bleeding, lymphocele, and vascular complications. Conclusion: Surgeons at the beginning of their learning curve have a longer TOT and more urological complications, without an effect on postoperative bleeding, lymphocele, infection and vascular complications. For interpretation of the outcomes, the quality and sample size of the evidence should be taken into consideratio

Tumour growth stimulation after partial hepatectomy can be reduced by treatment with tumour necrosis factor α

This study investigated whether partial hepatectomy enhances the growth of experimental liver metastases of colonic carcinoma in rats and whether treatment with recombinant human tumour necrosis factor (TNF) α can reduce this increased growth. Resection of 35 or 70 per cent of the liver was performed in inbred WAG rats, with sham-operated controls (five to eight animals per group). Immediately after surgery 5·105 CC531 colonic tumour cells were injected into the portal vein. After 28 days the animals were killed and the number of liver metastases counted. A 35 per cent hepatectomy induced a significant increase in the median number of liver metastases (28 versus 3 in controls), whereas a 70 per cent resection provoked excessive growth, consistently leading to more than 100 liver metastases and a significantly increased wet liver weight in all animals. TNF-α was given intravenously to rats following 70 per cent hepatectomy or sham operation in a dose of 160 μg/kg three times per week. This had only a marginal effect on tumour development in sham-operated rats but was very effective following partial hepatectomy (median 45 liver metastases). These observations confirm previous findings that surgical metastasectomy may act as a ‘double-edged sword’ by provoking outgrowth of dormant tumour cells and suggest that adjuvant treatment with TNF-α may be of benefit in patients undergoing resection of metastases