title: Advantages of laparoscopic compared to conventional surgery are not related to an innate immune response of peritoneal immune activation: an animal study in rats.
abstract: OBJECTIVE
  Laparoscopic surgery (LS) has proved superior compared to conventional surgery (CS) regarding morbidity, length of hospital stay, rate of wound infection and time until recovery. An improved preservation of the postoperative immune function is assumed to contribute to these benefits though the role of the local peritoneal immune response is still poorly understood. Our study investigates the peritoneal immune response subsequent to abdominal surgery and compares it between laparoscopic and conventional surgery to find an immunological explanation for the clinically proven benefits of LS.
  
  
  METHODS
  Wistar rats (N = 140) underwent laparoscopic cecum resection (LCR; N = 28), conventional cecum resection (CCR; N = 28), laparoscopic sham operation (LSO; N = 28), conventional sham operation (CSO; N = 28), or no surgical treatment (CTRL; N = 28). Postoperatively, peritoneal lavages were performed, leukocytes isolated and analyzed regarding immune function and phagocytosis activity.
  
  
  RESULTS
  Immune function was inhibited postoperatively in animals undergoing LCR or CCR compared to CTRL reflected by a lower TNF-α (CTRL 3956.65 pg/ml, LCR 2018.48 pg/ml (p = 0.023), CCR 2793.78 pg/ml (n.s.)) and IL-6 secretion (CTRL 625.84 pg/ml, LCR 142.84 pg/ml (p = 0.009), CCR 169.53 pg/ml (p = 0.01)). Phagocytosis was not affected in rats undergoing any kind of surgery compared to CTRL. Neither cytokine secretion nor phagocytosis activity differed significantly between laparoscopic and conventional surgery.
  
  
  CONCLUSIONS
  According to our findings the benefits associated with LS compared to CS cannot be explained by differences in the postoperative peritoneal innate immune response. Further studies are needed to elucidate the causes for a more favorable postoperative outcome in patients after LS compared to CS.
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany. Philipp.Lingohr@ukb.uni-bonn.de.
authors.forename: Philipp
authors.initials: P
authors.lastname: Lingohr
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Jonas
authors.initials: J
authors.lastname: Dohmen
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Hanno
authors.initials: H
authors.lastname: Matthaei
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Timo
authors.initials: T
authors.lastname: Schwandt
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Kathy
authors.initials: K
authors.lastname: Stein
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Gun-Soo
authors.initials: GS
authors.lastname: Hong
authors.affiliation: Institute of Laboratory Animal Science, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Steitz
authors.affiliation: Institute of Pathology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Longerich
authors.affiliation: Department of Radiotherapy and Radiation Oncology, University of Düsseldorf, Moorenstraße 5, 40225, Düsseldorf, Germany.
authors.forename: Edwin
authors.initials: E
authors.lastname: Bölke
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Wehner
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Straße 25, 53127, Bonn, Germany.
authors.forename: Jörg C
authors.initials: JC
authors.lastname: Kalff
mesh_terms: D000818:Animals; D002432:Cecum / Q000601:surgery*; D016207:Cytokines; D005260:Female; D007113:Immunity, Innate / Q000502:physiology*; D010535:Laparoscopy; D008297:Male; D010533:Peritoneal Lavage; D010537:Peritoneum / Q000276:immunology*; D010587:Phagocytosis; D051381:Rats; D017208:Rats, Wistar
chemical_list: D016207:Cytokines
keywords: Cecum resection; Laparoscopy; Macrophages; Monocytes; Peritoneal immune response; Rats