1 mL, 0.5 mg?mL?1, Sigma Chemical Co.) enabled analysis of leucocyte�Cendothelium interactions in the microvascular bed. For observations of the microcirculation, we used a modified Olympus contain microscope (BX50WI, Olympus Optical Co. GmbH, Hamburg, Germany) and recorded videos on a computer for later off-line analysis of leucocyte-endothelium interactions. Twenty-five C57BL/6 wild-type and five LFA-1 gene-targeted male mice were used, two to six postcapillary venules were evaluated in each animal and leucocyte rolling was measured by counting the number of cells rolling along the endothelial lining for 20 s and is expressed as cells?min?1. Leucocyte adhesion was measured by counting the number of cells that adhered and remained stationary for more than 30 s during the observation time and is expressed as cells?mm?2.

Certain animals received an anti-P-selectin antibody (40 ��g, i.v., clone RB40.34, BD Biosciences Pharmingen) immediately before capturing microphotographs of the postcapillary venules in the pancreas in order to abolish leucocyte rolling and thereby enable visualization of the remaining leucocytes that were firmly adherent to the endothelium. Statistics Data are presented as mean values �� SEM. Statistical evaluations were performed by using non-parametrical tests (Mann�CWhitney). P < 0.05 was considered significant and n represents the number of animals. Results Role of LFA-1 in taurocholate-induced tissue damage in the pancreas First, we examined LFA-1 expression at the mRNA and protein level in the LFA-1 gene-targeted mice used herein and found that these animals completely lacked LFA-1 (Figure S1).

Retrograde infusion of sodium taurocholate into the pancreatic duct enhanced serum amylase levels by nearly 16-fold (Figure 1). Taurocholate-induced serum levels of amylase were reduced by more than 70% in LFA-1-deficient animals and in mice treated with an antibody against LFA-1 (Figure 1). Tissue damage was evaluated by quantification of acinar cell necrosis, oedema formation and haemorrhage in the pancreas. Taurocholate-induced acinar cell necrosis, oedema formation and interstitial haemorrhage were markedly attenuated in LFA-1 gene-targeted animals and in mice treated with the anti-LFA-1 antibody (Figure 2).

Moreover, morphological examination of the pancreas revealed normal microstructure in control animals, whereas taurocholate challenge caused severe Dacomitinib destruction of the pancreatic tissue structure characterized by extensive cell necrosis, oedema and massive infiltration of neutrophils (Figure 3). However, the structure of the pancreas was protected in LFA-1-deficent and in anti-LFA-1 antibody-treated mice challenged with taurocholate (Figure 3). Figure 1 Serum amylase (��Kat?L?1) in wild-type (WT) and lymphocyte function antigen-1 (LFA-1)-deficient mice. Pancreatitis was induced by infusion of sodium taurocholate into the pancreatic duct. Control mice received saline alone. Certain …