Neutrophil activity in sepsis: a systematic review

The neutrophil is an important cell in host defense against infections, acting as the first line of microorganism control. However, this cell exhibits dysregulated activity in sepsis and may contribute to the pathogenesis of the disease. This systematic review aimed to highlight the major scientific findings regarding neutrophil activity in sepsis reported in clinical and experimental research published in the last 10 years. The search was conducted in the Virtual Health Library of PAHO-WHO (BVS) and PubMed databases, and articles published between January 2007 and May 2017 in Portuguese, English, and Spanish were eligible. Article selection was carried out independently by two reviewers (CB and IB). A total of 233 articles were found, of which 87 were identified on PubMed and 146 on BVS. Eighty-two articles were duplicates. Of the remaining 151 articles, 19 met the inclusion criteria after title, abstract, and full-text analysis. Overall, research in clinical samples and animal models of sepsis showed reduced capacity of neutrophils to migrate and delayed apoptosis, but there was no consensus on the phagocytic activity of neutrophils in sepsis. Molecules, such as pentraxin 3 (PTX3), have been analyzed as potential diagnostic markers in sepsis but the diversity of soluble molecules detected in blood samples of sepsis patients did not enable further understanding of the correlation of these circulating molecules with neutrophil activity during sepsis. Optimal understanding of the function of neutrophils in sepsis remains a challenge that, if overcome, would eventually allow targeted therapeutic interventions in patients affected by this severe syndrome.

Airway Neutrophil Activation and Protease Imbalance in Airway of Children with Foreign-Body Aspiration / 实用儿科临床杂志

Objective To observe neutrophil activation and protease imbalance in airway of children after foreign-body aspiration(FBA).Methods Bronchoalveolar lavage fluid(BALF) was obtained through fiberoptic bronchoscopy.The supernatant was assayed for the concentration of neutrophil elastase(NE) using enzyme-linked immunosorbent assay(ELISA) and elastase inhibition capacity(EIC)/free elastase activity using a colorimetric assay.The cell pellet were smeared for the expression of ?1-antitrypsin(?1-AT) using cellular immunohisto-chemistry and cytologic analysis by Wright-Giemsa stain.Results Percentage of neutrophil,concentration of NE and the expression of ?1-AT in BLAF group,pair group and pneumonia group significantly increased compared with that of control group(Pa0.05).The ratio of Lib NE in FBA,par and peumcria group was 30.3%,27.3% and 22.7%.Conclusions FBA induces similar airway neutrophil activation and protease imbalance to bacterial pneumonia.The contralateral airway showes the same change as the foreign body side.