Assessment of inflammatory response and sequestration of blood iron transferrin complexes in a rat model of lung injury resulting from exposure to low-frequency shock waves

Abstract

The observed dynamics in polymorphonuclear leukocyte alterations in peripheral blood after OPW exposure were similar to those found recently in clinical observations of nonpenetrating injury and in animal models of infectious insults. Therefore, our data suggest that the main pattern of proinflammatory alterations in the rat model of lung injury induced by exposure to long-duration shock wave is similar to patterns that are characteristic of major trauma. The data further suggest that the expression of polymorphonuclear leukocyte CD11b and the response of iron-transferrin complex can be considered as potential surrogate markers in blood for systemic alterations following OPW-induced injury and, therefore, warrant further investigation in a human pilot study.

CD43Lo classical monocytes participate in the cellular immune response to isolated primary blast lung injury

“…We saw significant increases in neutrophils in the blood across all time points, which may in part be driven by circulating chemokines and complement products previously reported to be elevated in PBLI 12,19,36,37 . Additionally, we observed a rapid increase in neutrophils in the lung at 1 and 3hr, returning to baseline by 6hr.…”

“…PBLI causes damage to lung tissue that promotes cellular infiltration, through the destructive effects of stress and shear waves at air-fluid tissue boundaries. In PBLI, studies have shown neutrophil infiltration histologically or by assaying activation markers such as MPO in BALF or lung homogenates [9][10][11][12]14,18,19,34 . Our histological data showed marked cellular infiltration and free erythrocytes due to alveolar haemorrhage consistent with previous human and rodent reports 11,35 .…”

“…PBLI is known to elicit mobilisation of neutrophils from the bone marrow into the blood 9,11,12 and promote their activation 19,37 . We saw significant increases in neutrophils in the blood across all time points, which may in part be driven by circulating chemokines and complement products previously reported to be elevated in PBLI 12,19,36,37 .…”

“…Studies investigating the subsequent immune response have been reported most commonly in rats [5][6][7][8][9][10] , mice [11][12][13][14][15] and swine 16,17 . These studies have offered overwhelming evidence of the neutrophil response to PBLI in animal models, with increases in circulating and broncho-alveolar lavage fluid (BALF) neutrophils, increases in Myeloperoxidase (MPO) activity in the lung, and neutrophil staining by histology [9][10][11][12]14,18,19 . However, the immune response to tissue damage differs depending on the type of organ injured and their local physiology; it remains unclear what specific contribution blast injuries to different parts of the body make to the inflammatory response that ensues.…”

Rat Injury Model under Controlled Field-Relevant Primary Blast Conditions: Acute Response to a Wide Range of Peak Overpressures

“…It is possible that both these factors acting together or alone can generate highfrequency stress waves and lower-frequency shear waves, and both types are potentially injurious to the tissue. 13,41 Experimental evidence collected in the past suggests that blastrelated injury is governed by three key input parameters associated with the shockwave: (1) peak overpressure, (2) the overpressure (positive phase) duration, and (3) positive phase impulse (the integral of overpressure in the time domain). To evaluate the effect of blast exposure, various animal models were exposed to different forms of blast ranging from direct exposure to live explosives and controlled blast waves.…”