Specific amino acid (L-arginine) requirement for the microbiostatic activity of murine macrophages.
AUTOR(ES)
Granger, D L
RESUMO
The microbiostatic action of macrophages was studied in vitro employing peritoneal cytotoxic macrophages (CM) from mice acting against Cryptococcus neoformans cultured in Dulbecco's medium with 10% dialyzed fetal bovine serum. Fungistasis was measured using electronic particle counting after lysis of macrophages with detergent. Macrophage fungistasis failed in medium lacking only L-arginine. Complete fungistasis was restored by L-arginine; restoration was concentration dependent, maximal at 200 microM. Deletion of all other essential amino acids did not abrogate fungistasis provided that L-arginine was present. Of twenty guanido compounds, including D-arginine, only three (L-arginine, L-homoarginine, and L-arginine methylester) supported fungistasis. Known activators or mediators of macrophage cytotoxicity (endotoxin, interferon gamma, tumor necrosis factor) did not replace L-arginine for CM-mediated fungistasis. The guanido analogue NG-monomethyl-L-arginine was a potent competitive inhibitor of CM-mediated fungistasis giving 50% inhibition at an inhibitor/L-arginine ratio of 1:27. Although CM completely blocked fungal reproduction via an L-arginine-dependent mechanism, the majority of the dormant fungi remained viable. Thus, this mechanism is viewed as a microbiostatic process similar or identical to the tumoristatic effect of macrophages. This suggests the production of a broad spectrum biostatic metabolite(s) upon consumption of L-arginine by cytotoxic macrophages.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=329641Documentos Relacionados
- Metabolic fate of L-arginine in relation to microbiostatic capability of murine macrophages.
- Amino Acid Transport in Suspension-Cultured Plant Cells 1: III. COMMON CARRIER SYSTEM FOR THE UPTAKE OF l-ARGININE, l-ASPARTIC ACID, l-HISTIDINE, l-LEUCINE, AND l-PHENYLALANINE
- The metabolism of L-arginine and its significance for the biosynthesis of endothelium-derived relaxing factor: cultured endothelial cells recycle L-citrulline to L-arginine.
- Effect of L-arginine, dimercaptosuccinic acid (DMSA) and the association of L-arginine and DMSA on tissue lead mobilization and blood pressure level in plumbism
- The metabolism of L-arginine and its significance for the biosynthesis of endothelium-derived relaxing factor: L-glutamine inhibits the generation of L-arginine by cultured endothelial cells.