Complete Genome Sequence of Pseudomonas aeruginosa XN-1, Isolated from the Sputum of a Severe Pneumonia Patient

A novel structurally identified epitope delivered by macrophage membrane-coated PLGA nanoparticles elicits protection against Pseudomonas aeruginosa

The increasing prevalence of antibiotic resistance by Pseudomonas aeruginosa (PA) raises an urgent need for an effective vaccine. The outer membrane proteins of PA, especially those that are upregulated during infection, are ideal vaccine targets. However, the strong hydrophobicity of these proteins hinders their application for this purpose. In this study, we selected eight outer membrane proteins from PA with the most significantly upregulated expression. Their extracellular loops were analyzed and screened by using sera from patients who had recovered from PA infection. As a result, a novel immunogenic epitope (Ep_167-193) from PilY1 (PA4554) was found. Moreover, we constructed a macrophage membrane-coated PLGA (poly lactic-co-glycolic acid) nanoparticle vaccine carrying PilY1 Ep_167-193 (PNPs@M-Ep_167-193) that elicits a Th2 immune response and confers adequate protection in mice. Our data furnished the promising vaccine candidate PNPs@M-Ep_167-193 while providing additional evidence for structure-based epitope identification and vaccine design.

Vaccination induces rapid protection against bacterial pneumonia via training alveolar macrophage in mice

Vaccination strategies for rapid protection against multidrug-resistant bacterial infection are very important, especially for hospitalized patients who have high risk of exposure to these bacteria. However, few such vaccination strategies exist due to a shortage of knowledge supporting their rapid effect. Here, we demonstrated that a single intranasal immunization of inactivated whole cell of Acinetobacter baumannii elicits rapid protection against broad A. baumannii-infected pneumonia via training of innate immune response in Rag1-/- mice. Immunization-trained alveolar macrophages (AMs) showed enhanced TNF-α production upon restimulation. Adoptive transfer of immunization-trained AMs into naive mice mediated rapid protection against infection. Elevated TLR4 expression on vaccination-trained AMs contributed to rapid protection. Moreover, immunization-induced rapid protection was also seen in Pseudomonas aeruginosa and Klebsiella pneumoniae pneumonia models, but not in Staphylococcus aureus and Streptococcus pneumoniae model. Our data reveal that a single intranasal immunization induces rapid and efficient protection against certain Gram-negative bacterial pneumonia via training AMs response, which highlights the importance and the possibility of harnessing trained immunity of AMs to design rapid-effecting vaccine.

Effect of care bundles in the nursing of severe pneumonia

OBJECTIVE

To explore the effect of care bundles and analyze the influence of different angles of turning over on the sputum excretion of mechanically ventilated patients with severe pneumonia.

METHODS

120 patients with severe pneumonia in our hospital from October 2016 to October 2019 were equally randomized into four groups, each with 30, according to the date of admission. The control group was given conventional nursing and placed in a position of left 30°-half lying-right 30°; the group A was given comprehensive care bundles and placed in a position of left 30°-half lying-right 30°; the group B was given comprehensive care bundles and placed in a position of left 45°-half lying-right 45°, and the group C was given comprehensive care bundles and placed in a position of 60° left-half lying-60° right. The respiratory rates and oxygenation indexes of patients in the three groups (group A, B, C) in lateral position at 2 h and 6 h respectively before and after mechanical ventilation were compared. And we compared the nursing efficiency and satisfaction.

RESULTS

The control group showed lower nursing efficiency and satisfaction compared with the group A (P<0.05). The group B and C showed higher oxygenation index after six hours of ventilation compared with group A (P<0.05). After two hours of mechanical ventilation, the group B and C showed lower respiratory rate and higher oxygenation index compared with the group A, and the respiratory rate and oxygenation index of the group B were closest to the normal range (P<0.05).

CONCLUSION

The sputum excretion effect of mechanically ventilated patients with severe pneumonia was the best if they were placed in a position of left 45°-half lying-right 45° and given comprehensive care bundles.