scholarly journals Defective Bactericidal Activity of Monocytes in Fatal Granulomatous Disease

Blood ◽  
1969 ◽  
Vol 33 (6) ◽  
pp. 813-820 ◽  
Author(s):  
GLENN E. RODEY ◽  
B. H. PARK ◽  
DOROTHY B. WINDHORST ◽  
ROBERT A. GOOD

Abstract The bactericidal activity of monocyte-rich cell suspensions obtained from the peripheral blood of patients with fatal granulomatous disease (FGD), their mothers and normal controls was studied. Defective killing of Staphylococcus aureus, Strain 502A, by monocyte-rich cell suspensions from children with FGD was found when compared with monocyte-rich suspensions from normal controls. This defect, less severe, was also observed in the mothers of affected patients. In this selected population of mothers, the monocyte defect varied in parallel with the previously described neutrophil defect.

Author(s):  
A. V. Zuraev ◽  
A. V. Lishai ◽  
Yu. V. Grigoriev ◽  
O. A. Ivashkevich

A number of 1,4- and 1,4,5-triazoles have been synthesized using a modified catalytic system for the Huisgen [3+2] cycloaddition reaction. The bactericidal activity of the synthesized compounds has been studied. The synthesized derivatives of 1H-1,2,3-triazoles have demonstrated higher antibacterial activities in relation to the pathogen Staphylococcus aureus strain which can be comparable with the clinically used antibiotic “Cefotaxime”.


Blood ◽  
1982 ◽  
Vol 60 (5) ◽  
pp. 1151-1158 ◽  
Author(s):  
GR Donowitz ◽  
GL Mandell

Abstract Adults with chronic granulomatous disease of childhood (CGD) have been described who remain relatively free of infection despite markedly abnormal neutrophil function. Monocyte function in four adults with this mild or atypical CGD syndrome was examined and compared to that of normal controls and to that of two patients with the more severe or classic CGD syndrome. Monocytes from patients with atypical CGD killed 75.7% +/- 2.6% (mean +/- SEM) of ingested organisms at 30 min, while monocytes from the patients with classic CGD killed only 50.3% +/- 4.2% of bacteria (p less than 0.001). The difference in bactericidal activity between atypical CGD monocytes and normal monocytes was relatively small (75.7% +/- 2.6% versus 88.1% +/- 3.7%, respectively) but was statistically significant (p = 0.007). Monocytes from both atypical and classic CGD patients showed markedly impaired oxidative metabolism. Differences in monocyte bactericidal activity may explain why atypical CGD patients have fewer infections than classic CGD patients. The presence of nonoxidative bactericidal mechanisms in atypical CGD monocytes is suggested by the demonstration of bactericidal activity despite severe oxidative metabolic defects.


Blood ◽  
1982 ◽  
Vol 60 (5) ◽  
pp. 1151-1158
Author(s):  
GR Donowitz ◽  
GL Mandell

Adults with chronic granulomatous disease of childhood (CGD) have been described who remain relatively free of infection despite markedly abnormal neutrophil function. Monocyte function in four adults with this mild or atypical CGD syndrome was examined and compared to that of normal controls and to that of two patients with the more severe or classic CGD syndrome. Monocytes from patients with atypical CGD killed 75.7% +/- 2.6% (mean +/- SEM) of ingested organisms at 30 min, while monocytes from the patients with classic CGD killed only 50.3% +/- 4.2% of bacteria (p less than 0.001). The difference in bactericidal activity between atypical CGD monocytes and normal monocytes was relatively small (75.7% +/- 2.6% versus 88.1% +/- 3.7%, respectively) but was statistically significant (p = 0.007). Monocytes from both atypical and classic CGD patients showed markedly impaired oxidative metabolism. Differences in monocyte bactericidal activity may explain why atypical CGD patients have fewer infections than classic CGD patients. The presence of nonoxidative bactericidal mechanisms in atypical CGD monocytes is suggested by the demonstration of bactericidal activity despite severe oxidative metabolic defects.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S561-S562
Author(s):  
Jacinda Abdul-Mutakabbir ◽  
Razieh Kebriaei ◽  
Kyle Stamper ◽  
Philip Maassen ◽  
Michael J Rybak

Abstract Background Glycopeptides and lipopeptides, more specifically vancomycin (VAN) and daptomycin (DAP) have been principally utilized in treating MRSA infections. Due to continued use, MRSA strains have developed resistance to these antibiotics including vancomycin intermediate susceptible Staphylococcus aureus (VISA) and daptomycin non-susceptible strains (DNS). Lipoglycopeptides; notably dalbavancin (DAL), have been employed due to their ease of administration and enhanced activity against highly resistant S. aureus. As previously demonstrated, the use of β-lactams, specifically cefazolin (CFZ) in combination with anti-MRSA drug therapy has been effective in eradicating S. aureus complicated by increased resistance. The objective of this study was to evaluate the activity of DAL, VAN, and DAP, alone and in combination with CFZ in a pharmacokinetic/pharmacodynamic (PK/PD) model. Methods The well-characterized DNS-VISA strain, D712, was evaluated in eight different regimens in duplicate via a one-compartment 7-day PK/PD model. The experimental regimens were as follows: D712 growth control, DAL 1500 mg given on day 1, VAN 2 g given every 12 hours, DAP 10 mg/kg once-daily, CFZ 2 g given every 8 hours and DAL, DAP, and VAN in combination with CFZ. Results The combinations of DAL+CFZ, VAN+CFZ, and DAP+CFZ demonstrated a significant log10 CFU/mL reduction (more than 5 log 10 CFU/mL and up to detection limit), compared with each drug used as monotherapy (P < 0.001). Neither DAP nor VAN demonstrated sustained bactericidal activity, (represented by a >3-log10 CFU/mL reduction from baseline) and resulted in significant regrowth, when administered alone. However, the DAP +CFZ, and VAN+CFZ combination models demonstrated bactericidal activity at 4 hours and 24 hours, respectively. While DAL alone did demonstrate bactericidal activity, the DAL+CFZ combination was more rapidly bactericidal, achieving a > 3-log reduction from baseline in 8 hours vs. 48 hours (P < 0.05). Conclusion The combination of DAL, VAN, or DAP with CFZ demonstrated significantly improved activity against this multiple drug-resistant S. aureus strain. Further research is warranted, both in vivo and in vitro, to explore the synergistic capabilities of anti-MRSA drug therapy in combination with β-lactams. Disclosures All authors: No reported disclosures.


Author(s):  
Hui Shi ◽  
Jiaqin Tang ◽  
Cuiying An ◽  
Lingkang Yang ◽  
Xianxuan Zhou

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 645
Author(s):  
Mohamed Ibrahem Elhawy ◽  
Sylvaine Huc-Brandt ◽  
Linda Pätzold ◽  
Laila Gannoun-Zaki ◽  
Ahmed Mohamed Mostafa Abdrabou ◽  
...  

Staphylococcus aureus continues to be a public health threat, especially in hospital settings. Studies aimed at deciphering the molecular and cellular mechanisms that underlie pathogenesis, host adaptation, and virulence are required to develop effective treatment strategies. Numerous host-pathogen interactions were found to be dependent on phosphatases-mediated regulation. This study focused on the analysis of the role of the low-molecular weight phosphatase PtpB, in particular, during infection. Deletion of ptpB in S. aureus strain SA564 significantly reduced the capacity of the mutant to withstand intracellular killing by THP-1 macrophages. When injected into normoglycemic C57BL/6 mice, the SA564 ΔptpB mutant displayed markedly reduced bacterial loads in liver and kidney tissues in a murine S. aureus abscess model when compared to the wild type. We also observed that PtpB phosphatase-activity was sensitive to oxidative stress. Our quantitative transcript analyses revealed that PtpB affects the transcription of various genes involved in oxidative stress adaptation and infectivity. Thus, this study disclosed first insights into the physiological role of PtpB during host interaction allowing us to link phosphatase-dependent regulation to oxidative bacterial stress adaptation during infection.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S622-S623
Author(s):  
Alisa W Serio ◽  
S Ken Tanaka ◽  
Kelly Wright ◽  
Lynne Garrity-Ryan

Abstract Background In animal models of Staphylococcus aureus infection, α-hemolysin has been shown to be a key virulence factor. Treatment of S. aureus with subinhibitory levels of protein synthesis inhibitors can decrease α-hemolysin expression. Omadacycline, a novel aminomethylcycline antibiotic in the tetracycline class of bacterial protein biosynthesis inhibitors, is approved in the United States for treatment of community-acquired bacterial pneumonia (CABP) and acute bacterial skin and skin structure infections (ABSSSI) in adults. This study was performed to determine the durability of inhibition and effect of subinhibitory concentrations of omadacycline on S. aureus hemolytic activity. Methods All experiments used the methicillin-sensitive S. aureus strain Wood 46 (ATCC 10832), a laboratory strain known to secrete high levels of α-hemolysin. Minimum inhibitory concentrations (MICs) of omadacycline and comparator antibiotics (tetracycline, cephalothin, clindamycin, vancomycin, linezolid) were determined. Growth of S. aureus with all antibiotics was determined and the percentage of hemolysis assayed. “Washout” experiments were performed with omadacycline only. Results S. aureus cultures treated with 1/2 or 1/4 the MIC of omadacycline for 4 hours showed hemolysis units/108 CFU of 47% and 59% of vehicle-treated cultures, respectively (Fig. 1A, 1B). In washout experiments, treatment with as little as 1/4 the MIC of omadacycline for 1 hour decreased the hemolysis units/108 CFU by 60% for 4 hours following removal of the drug (Table 1). Figure 1 Table 1 Conclusion Omadacycline inhibited S. aureus hemolytic activity in vitro at subinhibitory concentrations and inhibition was maintained for ≥ 4 hours after removal of extracellular drug (Fig. 2). The suppression of virulence factors throughout the approved omadacycline dosing interval, in addition to the in vitro potency of omadacycline, may contribute to the efficacy of omadacycline for ABSSSI and CABP due to virulent S. aureus. This finding may apply to other organisms and other virulence factors that require new protein synthesis to establish disease. Figure 2 Disclosures Alisa W. Serio, PhD, Paratek Pharmaceuticals, Inc. (Employee, Shareholder) S. Ken Tanaka, PhD, Paratek Pharmaceuticals, Inc. (Employee, Shareholder) Kelly Wright, PharmD, Paratek Pharmaceuticals, Inc. (Employee, Shareholder) Lynne Garrity-Ryan, PhD, Paratek Pharmaceuticals, Inc. (Employee, Shareholder)


Sign in / Sign up

Export Citation Format

Share Document