Interactions of Escherichia coli and Proteus mirabilis with mouse mononuclear phagocytes.
Interactions of Escherichia coli and Proteus mirabilis with mouse mononuclear phagocytes.
复制标题
大肠杆菌和奇异变形杆菌与小鼠单核吞噬细胞的相互作用。
DOI：
10.1099/00222615-33-3-153
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发表时间：
1990
影响因子：
3
通讯作者：
Nelson,RD
中科院分区：
文献类型：
--
作者：
Wells,CL;Jechorek,RP;Nelson,RD
Five strains of enterobacteria (three ofEscherichia coliand two ofProteus mirabilis) were studied to assess and compare their phagocytic uptake and intracellular killing by mouse macrophages. Each strain was injected intraperitoneally into separate groups of mice and peritoneal exudate cells were harvested after 3 min for phagocytosis to occurin vivo. Acridine orange staining showed that there were approximately 10-fold fewer intracellularP. mirabilisthanE. coli cells. The average numbers of viable intracellular bacteria per leucocyte were 0.03 and 0.02 forP. mirabilisstrains M13 and H1, respectively, and 0.48, 0.45, and 0.28 forE. colistrains M14, A-D M5 and H40. Thus, bothP. mirabilisstrains were ingested less readily than any of the threeE. colistrains (p<0.01). The rates of in-vitro intracellular killing were similar for all five strains of bacteria. The intracellular killing constants (Kk) for the three mouse isolates were 0.017, 0.016 and 0.020 min forE. coliM14 and A-D M5, andP. mirabilisM13, respectively; the Kks for the two human isolates were 0.026 and 0.029/min forE. coliH40 andP. mirabilisH1, respectively. The Kks for all five strains were not significantly different. Assuming that the numbers of viable intracellular bacteria at the beginning of the assay represented 100% viability, 6-17% of the intracellular bacteria remained viable after 2 h, reflecting log103.9–5.6 bacteria (6–8) × 106peritoneal exudate cells. Intravenous injection of these five strains into separate groups of mice demonstrated that theP. mirabilisstrains were more virulent than theE. colistrains. Injection of eachP. mirabilisstrain was associated with ruffled fur and death, whereas mice given any of the threeE. colistrains remained visibly healthy and none died. Consistent with these observations, quantitation of viable bacteria in the liver and spleen showed that greater numbers ofP. mirabilisM13 than ofE. coliM14 or A-D M5 persisted in these organs; similarly greater numbers ofP. mirabilisH1 than ofE. coliH40 persisted in the liver and spleen. Because the rates of intracellular killing of these five strains were similar, the relative virulence of both strains ofP. mirabilisappeared to be associated with decreased phagocytic uptake rather than differences in intracellular survival.
