s. pneumoniae amri-sp1  (Albany Molecular Research)

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Streptococcus pneumoniae dose response. A: mice inoculated intranasally with between 2 × 107 and 5 × 108 colony-forming units (CFU) of S. pneumoniae developed hypothermia. Data are mean ± SD; n = 5 per dosing group. *P = 0.0025 compared with 2 × 107 by repeated measures ANOVA. B: S. pneumoniae caused between 0% and 100% mortality across this inoculation range; P = 0.0004 for log rank test for trend. C: histology (hematoxylin-eosin) at 7 days in survivors of 1 × 108 CFU reveals severe lobar pneumonia with airway occlusion by inflammatory exudate (arrow). D: at lower doses, airways were consistently patent (arrow), and a more modest inflammatory infiltrate was observed. E: S. pneumoniae causes hypothermia at doses greater than 3 × 107 CFU. *P = 0.0007, ^P < 0.0001 compared with 1 × 107 over the first 3 days postinfection by Dunnett’s multiple comparisons test. F: leukopenia was most pronounced at early time points and doses greater than 5 × 107 CFU. P = 0.16 for ANOVA. G: arterial oxygen saturation (SpO2) tended to decline in a dose-dependent manner for the first 72 h postinfection. *P = 0.04, ^P < 0.006 compared with 1 × 107 over the first 3 days postinfection by Dunnett’s multiple comparisons test. H: pulmonary edema as measured by excess extravascular lung water (in the interstitial and alveolar spaces) mirrored the changes in oxygenation. Overall ANOVA P = 0.0002; *P = 0.03 compared with 2 × 108, P = 0.01 compared with 5 × 107, P = 0.002 compared with 3 × 107, P < 0.0001 compared with 1 × 107 by Tukey’s multiple comparisons test. WBC, white blood cell.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques:

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Summary of animal models of pneumonia employing antibiotics

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques: In Situ, Permeability, Bacteria, Imaging, Activity Assay, Activation Assay, Coagulation, Clinical Proteomics, Produced, Cell Counting, Mouse Assay, Inhibition

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Influence of timing of first dose of antibiotics on the model. A: schematic depicting experimental procedures. Mice were inoculated with 1 × 108 colony-forming units (CFU) Streptococcus pneumoniae followed by 3 doses of ceftriaxone beginning at 6, 12, 24, or 36 h postinfection. B: there was a trend toward decreased survival as antibiotics (Abx) were delayed (n = 5–7 mice/group). P = 0.07 by log rank test. C: mice treated with antibiotics beginning at 6 h were significantly less hypothermic than untreated mice. Surprisingly, initiation of antibiotics 36 h postinfection caused more severe hypothermia than was observed without antibiotics. *P = 0.0005, ^P = 0.005 compared with no antibiotics by Dunnett’s multiple comparisons test. D: arterial hypoxemia was most severe in mice treated beginning 36 h postinfection. *P = 0.009 compared with no Abx by Dunnett’s multiple comparisons test. Significant mortality in the 36-h group reduced statistical power at 72 h. SpO2, arterial oxygen saturation. E: bronchoalveolar lavage (BAL) protein mirrored oxygenation with a 36-h delay in antibiotics causing higher BAL protein 72 h postinfection than in untreated mice. *P = 0.0009, ^P = 0.007, &P = 0.016 compared with no Abx by Dunnett’s multiple comparisons test.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques:

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Fine-tuning the antibiotic regimen to optimize 7-day survival. A: schematic depicting experimental procedures. Mice were inoculated with 1 × 108 colony-forming units (CFU) Streptococcus pneumoniae and then received 5 doses of ceftriaxone beginning 18, 24, or 30 h later. B: mice administered the first dose of antibiotics 18 h postinfection had 50% survival at 7 days. n = 10 mice per group. P = 0.23 for log rank test for trend. C: arterial oxygen saturation (SpO2) was similar across the 3 cohorts. Data are mean ± SD; P = 0.53 by ANOVA. D: body temperature trended lower with progressive delays in initiation of antibiotics. P = 0.11 by Kruskal–Wallis test.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques:

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Reducing the bacterial inoculum to improve 96-h survival while maintaining a moderately severe lung injury. A: schematic depicting experimental procedures. Mice were inoculated with either 1 × 108 or 7.5 × 107 colony-forming units (CFU) Streptococcus pneumoniae and then treated with 5 doses of ceftriaxone beginning 18 h postinfection. B: survival was ~80% at 96 h in the lower-dose group (*by log rank, n = 29–40 per group). C: mice were hypothermic between 24 and 96 h postinfection. *P < 0.0001, ^P = 0.0001, &P = 0.01 by Dunnett’s multiple comparisons test. D: peripheral leukopenia resolves between 48 and 96 h postinfection. *P < 0.0001 by unpaired t test. E: excess lung water (ELW), a measure of edema in the interstitial and alveolar spaces, remained elevated above baseline at 48 and 96 h postinfection. *P = 0.0024, ^P = 0.0099 by Dunn’s multiple comparisons test. F: wet-dry ratio was similarly increased at 48 and 96 h postinfection. *P < 0.0001 by Dunnett’s multiple comparisons test. G: mean arterial oxygen saturation (SpO2) remained in the high 80s during the entire 96 h postinfection, though the standard deviation was high. P = 0.33 by Kruskal–Wallis. H: bronchoalveolar lavage (BAL) protein peaked at 48 h postinfection and remained significantly above baseline at 96 h. *P < 0.0001 compared with no infection (No Infxn) and 96 h, ^P = 0.0194 compared with No Infxn by Tukey’s multiple comparisons test. I: BAL cellularity declined significantly between 48 and 96 h postinfection; *P = 0.0303 by Mann–Whitney. J: composition of BAL cellularity was mostly neutrophils and monocyte/macrophages at both time points, though there was a trend for an increase in lymphocytes between 48 and 96 h postinfection, from 0.5% to 3.7%, P = 0.12 by Mann–Whitney. WBC, white blood cell.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques: Standard Deviation, Infection, MANN-WHITNEY

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Histological evidence of lung injury. A–H: representative photomicrographs from the lungs of mice inoculated with 7.5 × 107 colony-forming units (CFU) Streptococcus pneumoniae followed by ceftriaxone beginning 18 h later. Alveolar septal thickness (asterisks) is greatest at 48 h without antibiotics (Abx), but it remains abnormal at 48 and 96 h in antibiotic-treated mice. Inflammation is primarily neutrophilic at 48 h with or without antibiotics (arrows); by 96 h postinfection, increasing numbers of monocytic and lymphocytic cells are identified (arrowheads). No Infxn, no infection.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques: Infection

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Persistent hypothermia and systemic inflammation despite bacterial clearance. A: schematic depicting experimental procedures. Mice were inoculated with 7.5 × 107 colony-forming units (CFU) Streptococcus pneumoniae and then treated with 5 doses of ceftriaxone beginning 18 h postinfection. Mice were euthanized at 96 or 168 h (4 or 7 days) postinfection. B: persistent hypothermia depicted as mean departure from preinfection temperature (± SD), n = 8–24 mice per time point. P = 0.24 by ANOVA. C: bacteremia resolved within 48 h in antibiotic-treated mice. Blood cultures remained negative 7 days postinfection, more than 4 days after the completion of antibiotics. *P = 0.0015 compared with 48 h, P = 0.0004 compared with 96 h, P = 0.0002 compared with 168 h, by Dunn’s multiple comparisons test. D: airspace pneumococci were cleared by 48 h postinfection and remained sterile at 96 h. About half of the mice had low levels of detectable bacteria 7 days postinfection, though these did not appear to be pneumococci based on the absence of hemolysis. *P = 0.003 compared with 48 h, P < 0.0001 compared with 96 h, P = 0.003 compared with 168 h, by Dunn’s multiple comparisons test. E: plasma IL-6 was significantly elevated 48 h postinfection (*P = 0.04 compared with no infection, P = 0.04 compared with 96 h, by Tukey’s multiple comparisons test). F: plasma TNF-α was significantly increased 48 h postinfection (*P = 0.025 compared with no infection, by Tukey’s multiple comparisons test). G: plasma IL-1β was elevated at 48 h (*P = 0.001 compared with no infection, P = 0.0003 compared with 96 h, by Tukey’s multiple comparisons test). Abx, antibiotics; BAL, bronchoalveolar lavage; Infxn, infection.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques: Sterility, Bacteria, Clinical Proteomics, Infection

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Evidence of renal and hepatic dysfunction. A: Schematic depicting experimental procedures. Mice were inoculated with 7.5 × 107 colony-forming units (CFU) Streptococcus pneumoniae and then treated with 5 doses of ceftriaxone beginning 18 h postinfection followed by euthanization at 48 or 96 h. B: level of blood urea nitrogen (BUN) was increased above baseline at 48 h postinfection, declining back to baseline by 96 h; *P = 0.05 compared with no infection (No Infxn), P = 0.009 compared with 96 h by Dunn’s multiple comparisons test. C: alanine aminotransferase (ALT) was significantly increased above baseline at 48 and 96 h postinfection. *P = 0.0004 compared with 48 h, P = 0.001 compared with 96 h by Tukey’s multiple comparisons test. D and F: hematoxylin-eosin (H&E)-stained sections of renal cortex reveals grossly normal glomeruli and tubules 48 h postinfection. E and G: H&E stained sections of liver parenchyma 48 h postinfection show no evidence of significant centrilobular necrosis or other histologic abnormalities.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques: Infection, Staining

Journal: American Journal of Physiology - Lung Cellular and Molecular Physiology

Article Title: Clinically relevant model of pneumococcal pneumonia, ARDS, and nonpulmonary organ dysfunction in mice

doi: 10.1152/ajplung.00132.2019

Figure Lengend Snippet: Fluid resuscitation increases lung edema and worsens lung compliance. A: schematic depicting experimental procedures. Mice were inoculated with 7.5 × 107 colony-forming units (CFU) Streptococcus pneumoniae and then treated with 5 doses of ceftriaxone beginning 18 h postinfection and then every 12 h × 5, with euthanization at 48 or 96 h. Half of the mice also received 700 μL ip of normal saline with each dose of antibiotics. B: saline treatment reversed hemoconcentration at 48 and 96 h, *P = 0.0046 vs. uninfected, P = 0.03 vs. saline at 48 h, by Tukey’s multiple comparisons test; ^P = 0.0003 vs. uninfected, P = 0.037 vs. saline at 96 h. C and D: saline administration did not significantly affect weight loss or hypothermia. Not significant by repeated measures ANOVA. E: mice treated with saline had normalized blood urea nitrogen (BUN), consistent with correction of renal hypoperfusion; *P = 0.026 by Mann–Whitney. F: saline treatment compared with no saline increased lung edema at 96 h as measured by wet-dry ratio. *P = 0 0.05 by Mann–Whitney. G: lung dynamic compliance at 96 h was significantly reduced by saline administration, *P = 0.047 by unpaired t test. H: lung compliance and wet-dry ratio were inversely correlated, Spearman r = −0.62, P = 0.02. I: there was a trend for lower arterial oxygenation between 24 and 96 h in fluid-resuscitated mice. SpO2, arterial oxygen saturation. P = 0.12 for group effect in repeated measures ANOVA. Abx, antibiotics; Infxn, infection.

Article Snippet: ( 44 ) * , 2014 , S. pneumoniae (AMRI-SP1, ATCC 49619) , BALB/c mice , Levofloxacin, ceftriaxone 150 or 50 mg/kg iv, alone or in combination , At 18 h, then q6 h × 3 doses , Abx synergy , Better bacterial killing and less lung inflammation, decreased myeloperoxidase with combination of levofloxacin and ceftriaxone; ceftriaxone monotherapy with higher lung TNF-α than no Abx.

Techniques: Saline, MANN-WHITNEY, Infection