Pleural macrophages are the dominant cell population in the thoracic cavity with an inflammatory cytokine profile similar to peritoneal macrophages

Abstract

Numerous human macrophage (mphi) subpopulations with different behavior have been identified in adults. It is well known that peritoneal mphi are activated by abdominal surgery and subsequently contribute to a systemic inflammatory response that leads to immune suppression, increased morbidity and mortality. Information on the role of pleural mphi in adults is scarce and information on their role in children is lacking. We investigated the behavior of pleural versus peritoneal mphi in children and adolescents. As a first step, we compared the cellular composition of the pleural and peritoneal surface in children and adolescents. Pleural and peritoneal lavages were performed in 21 patients undergoing non-contaminated laparoscopic and thoracoscopic surgical procedures. We observed a significantly higher percentage of mphi in the pleural compared to the peritoneal cavity with less lymphocytes, a small amount of polymorphonuclear cells (PMNs) and other cells. To further study the mphi inflammatory response, we measured the spontaneous and LPS triggered cytokine release of isolated pleural versus peritoneal mphi (IL-1beta, IL-6, and IL-10). The pattern of cytokine release was similar in both, pleural and peritoneal mphi. Directly after lavage, they showed a strong activation, with no difference between stimulated and non-stimulated cells. After 24 h resting, mphi of both compartments reacted to LPS with a similar significant increase in the cytokine release. In conclusion, our results demonstrate that pleural mphi represent the dominant cell population in the pleural cavity of the young. They show a similar inflammatory response as peritoneal mphi and should be considered to play a major role in the local inflammatory response to thoracic surgery.

CO2 pneumoperitoneum increases systemic but not local tumor spread after intraperitoneal murine neuroblastoma spillage in mice

“…In addition, it has been shown that CO 2 alters the functions of macrophages and polymorphonuclear cells in the peritoneal and thoracic cavity [19,32,35,36,41]. We have confirmed a downregulation of the release of various cytokines, free oxygen radicals, nitric oxide, and of the mitochondrial activity of macrophages and polymorphonuclear cells during and after CO 2 exposition via alteration of the extracellular pH [23,25].…”

Stimulatory effect of desipramine on lung metastases of adenocarcinoma MADB 106 in stress highly-sensitive and stress non-reactive rats

“…Peritoneal and pleural cavities are independent anatomical and functional compartments, but peritoneal and pleural macrophages have similar functional and phenotypic properties (Dörger et al, 2001;Gjomarkaj et al, 1999;Shimotakahara et al, 2007). We examined peritoneal and pleural macrophages separately in order to discriminate potential effects of direct drug action (in the case of peritoneal cells) from indirect effects of the drug (in the case of pleural cells).…”

Cellular Defences of the Lung: Comparative Perspectives

“…Contrary to their well-serving protective activities, under certain conditions, macrophages function as a 'double-edged sword': they can initiate, exacerbate, and prolong inflammatory responses that cause immune suppression and progression of pathologies like cancer, leading to higher morbidity and mortality (e.g. Brain, 1976Brain, , 1980Brain, , 1992Brain et al, 1984;Bowden, 1987;Warner, 1996;Yanagawa et al, 1996;Fireman et al, 1999;Ishii et al, 2005;Parbhakar et al, 2005;Rubovitch et al, 2007;Shimotakahara et al, 2007;Sica and Bronte, 2007;Kaczmarek et al, 2008;Gill et al, 2008;Biswas et al, 2008;Aharonson-Raz and Singh, 2010;De Palma and Lewis, 2011).…”