摘要：To study the anti-infectious effect of a vascular allograft, the antimicrobial activity of tryptophan metabolites mediated by indoleamine 2,3-dioxygenase was determined. The growth of methicillin-resistant Staphylococcus aureus (MRSA) over 10 h in extracts from post-transplantation vascular allograft was significantly slower than that of extracts from non-transplantation vascular allograft regardless of the presence of tryptophan ( p <0.05). When the antimicrobial activity of the tryptophan metabolites in the L -tryptophan– L -kynurenine pathway was examined, 3-hydroxy- DL -kynurenine and α-picolinic acid had strong antibacterial activity against MRSA, S. epidermidis , Escherichia coli , and multidrug-resistant Pseudomonas aeruginosa , although antimicrobial activities of anthranilic acid, 3-hydroxyanthranilic acid, and quinolinic acid against them were low. The results showed that, of the tested tryptophan metabolites, 3-hydroxy- DL -kynurenine and α-picolinic acid contributed to the anti-infectious effects of the allograft by inhibiting of the growth of microorganisms.
