"VSports最新版本" Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The VSports app下载. gov means it’s official. Federal government websites often end in . gov or . mil. Before sharing sensitive information, make sure you’re on a federal government site. .

Https

The site is secure V体育官网. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely. .

. 2008 Feb;52(2):427-34.
doi: 10.1128/AAC.00375-07. Epub 2007 Dec 10.

Replication of Colonic Crohn's Disease Mucosal Escherichia coli Isolates within Macrophages and Their Susceptibility to Antibiotics

Sreedhar Subramanian  1 , Carol L Roberts, C Anthony Hart, Helen M Martin, Steve W Edwards, Jonathan M Rhodes, Barry J Campbell
Affiliations

Replication of Colonic Crohn's Disease Mucosal Escherichia coli Isolates within Macrophages and Their Susceptibility to Antibiotics

Sreedhar Subramanian et al. Antimicrob Agents Chemother. 2008 Feb.

Abstract

There is increasing evidence that Escherichia coli organisms are important in Crohn's disease (CD) pathogenesis. In CD tissue they are found within macrophages, and the adherent-invasive CD ileal E. coli isolate LF82 can replicate inside macrophage phagolysosomes. This study investigates replication and antibiotic susceptibility of CD colonic E. coli isolates inside macrophages. Replication of CD colonic E. coli within J774-A1 murine macrophages and human monocyte-derived macrophages (HMDM) was assessed by culture and lysis after gentamicin killing of noninternalized bacteria and verified by electron microscopy (EM). All seven CD colonic isolates tested replicated within J774-A1 macrophages by 3 h (6. 36-fold +/- 0. 7-fold increase; n = 7 isolates) to a similar extent to CD ileal E. coli LF82 (6. 8-fold +/- 0 VSports手机版. 8-fold) but significantly more than control patient isolates (5. 2-fold +/- 0. 25-fold; n = 6; P = 0. 006) and E. coli K-12 (1. 0-fold +/- 0. 1-fold; P < 0. 0001). Replication of CD E. coli HM605 within HMDM (3. 9-fold +/- 0. 7-fold) exceeded that for K-12 (1. 4-fold +/- 0. 2-fold; P = 0. 03). EM showed replicating E. coli within macrophage vacuoles. Killing of HM605 within J774-A1 macrophages following a 3-h incubation with antibiotics at published peak serum concentrations (C(max)) was as follows: for ciprofloxacin, 99. 5% +/- 0. 2%; rifampin, 85. 1% +/- 6. 6%; tetracycline, 62. 8% +/- 6. 1%; clarithromycin, 62. 1% +/- 5. 6% (all P < 0. 0001); sulfamethoxazole, 61. 3% +/- 7. 0% (P = 0. 0007); trimethoprim, 56. 3% +/- 3. 4% (P < 0. 0001); and azithromycin, 41. 0% +/- 10. 5% (P = 0. 03). Ampicillin was not effective against intracellular E. coli. Triple antibiotic combinations were assessed at 10% C(max), with ciprofloxacin, tetracycline, and trimethoprim causing 97% +/- 0. 0% killing versus 86% +/- 2. 0% for ciprofloxacin alone. Colonic mucosa-associated E. coli, particularly CD isolates, replicate within macrophages. Clinical trials are indicated to assess the efficacy of a combination antibiotic therapy targeting intramacrophage E. coli. .

PubMed Disclaimer

VSports最新版本 - Figures

FIG. 1.
FIG. 1.
CD mucosa-associated E. coli isolates replicate effectively inside J774-A1 macrophages and HMDMs. (A) Replication of E. coli strains isolated from CD (n = 8) and control patients (n = 6) within J774-A1 murine macrophages (mean ± standard error of the mean) compared to the nonpathogenic reference strain E. coli K-12. Replication is shown as the relative change after 3 h of growth within macrophages. Significant differences from E. coli K-12 replication rates are as follows: *, P < 0.05; **, P < 0.01; and ***, P < 0.001 (ANOVA). (B) Increased replication of CD colonic mucosa-associated E. coli strain HM605 is also shown within HMDMs (mean ± standard error of the mean) compared to the reference strain E. coli K-12. Differences from E. coli K-12 replication rates were significant (*, P < 0.05; Mann-Whitney U test). IBS, irritable bowel syndrome.
FIG. 2.
FIG. 2.
CD E. coli strain HM605 replicates in vacuoles of J774-A1 macrophages. Images are EM of J774-A1 macrophages infected with CD E. coli strain HM605 as described in Materials and Methods. Extracellular bacteria were eliminated with gentamicin. Filled arrows indicate HM605 within vacuoles. HM605 survives and replicates within vacuolar structures without affecting cellular morphology. Hollow arrows indicate replicating HM605. Bar, 2 μm.
FIG. 3.
FIG. 3.
Azithromycin, ciprofloxacin, clarithromycin, rifampin, tetracycline, and trimethoprim kill CD E. coli HM605 within macrophages. Values are the percentages (mean ± standard error of the mean, n = 3) of CD E. coli strain HM605 bacteria killed by the indicated antibiotics. Similar concentrations of antibiotics also effectively killed HM605 in medium alone. Ampicillin did not affect viability of intracellular HM605 within macrophages. However, similar concentrations of ampicillin did cause killing of HM605 in medium alone. Significant differences from survival of HM605 within J774-A1 macrophages are indicated as follows: *, P < 0.05; **, P < 0.01; and ***, P < 0.001. (***), P < 0.001 for survival of HM605 in medium alone.
FIG. 4.
FIG. 4.
Ciprofloxacin affects viability of CD E. coli strain HM605 in J774-A1 macrophages: EM of J774-A1 macrophages infected with CD E. coli HM605 in the presence of 0.1 μg/ml ciprofloxacin. Extracellular bacteria were eliminated with gentamicin. Arrows indicate the presence of bacterial debris within vacuoles. Bar, 5 μm.
FIG. 5.
FIG. 5.
The combination of either ciprofloxacin, trimethoprim, and tetracycline (CTT) or ciprofloxacin, trimethoprim, and rifampin (CTR) was able to achieve better killing than ciprofloxacin alone at 10% of Cmax. **, P < 0.01 in comparison to killing with ciprofloxacin alone. There was no significant difference in killing of HM605 within macrophages between single and combination antibiotics at Cmax.
See this image and copyright information in PMC

References

    1. Aderem, A. 2003. Phagocytosis and the inflammatory response. J. Infect. Dis. 187(Suppl. 2):S340-S345. - PubMed
    1. Agalar, C., S. Usubutun, and R. Turkyilmaz. 1999. Ciprofloxacin and rifampicin versus doxycycline and rifampicin in the treatment of brucellosis. Eur. J. Clin. Microbiol. Infect. Dis. 18:535-538. - PubMed
    1. Allen, L. A. 2003. Mechanisms of pathogenesis: evasion of killing by polymorphonuclear leukocytes. Microbes Infect. 5:1329-1335. - PubMed
    1. Alpuche-Aranda, C. M., E. L. Racoosin, J. A. Swanson, and S. I. Miller. 1994. Salmonella stimulate macrophage macropinocytosis and persist within spacious phagosomes. J. Exp. Med. 179:601-608. - PMC - PubMed
    1. Amsden, G. W. 2001. Advanced-generation macrolides: tissue-directed antibiotics. Int. J. Antimicrob. Agents 18(Suppl. 1):S11-S15. - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources