The peritoneal wall was then massaged gently and the fluid withdrawn. This was repeated twice with 80–90% recovery of the lavage fluid. The lavage fluid was pooled and centrifuged
at 300 g for 10 min at 25°C to recover leucocytes. find more The lavage solution was washed twice by resuspending in 10 ml sterile PBS (Gibco) and centrifuging at 300 g for 10 min. Leucocytes were counted using a haemocytometer. Approximately 5 × 106 cells per mouse were harvested. Peritoneal exudate cells from three wild-type FVB/N mice were isolated and pooled as described above and resuspended at 1 × 106 cells/ml. To this cell suspension, 50 µl of each monoclonal antibody (mAb) dye mix was added with incubation in the dark at 4°C for 30 min. The mAbs used for flow cytometry included: anti-CD11c [immunoglobulin (Ig)G1], phycoerythrin cyanine dye 7 (PE-Cy7), HL3, anti-Ly6G (IgG2b),
PE RB6-8C5, anti-CD4 (IgG2a), PE RM4-5, anti-CD49b (IgM) fluorescein isothiocyanate (FITC) DX5 (all from BD Pharmingen, Oxford, UK), anti-F4/80 (IgG2b) Tri-Color BM8 (Caltag, Buckingham, UK), anti-CD8 (IgG1) PE, anti-CD3 (IgG2B) FITC, anti-CXCR2 (IgG2a) allophycocyanin (APC) (R&D Systems, Abingdon, UK) and anti-B220 (IgG2a) Alexafluor (AF) 700 RA3-6B2 (Serotec, Kidlington, UK). For analysis of activation marker expression the mAbs used were anti-CD11b (IgG2b), FITC MI/70 and anti-CD69 (IgG1) PE-Cy7 H1·2F3 (BD Pharmingen). Following staining, the cells were washed twice with blocking buffer [PBS + 1% bovine serum albumin (BSA; Sigma-Aldrich) + 1% rat serum (Sigma-Aldrich) selleck chemicals llc + 1% hamster serum (Sigma-Aldrich) + 1% mouse serum (Dako Diagnostics,
Phloretin Dublin, Ireland) + 0·1% sodium azide (Sigma-Aldrich)] and fixed in 3% formalin for analysis. Relative fluorescence intensities were measured using a LSRII cytometer and BD Diva software (Becton Dickinson, Oxford, UK). For each sample, 20 000 events were recorded. The percentage of cells labelled with each mAb was calculated in comparison with cells stained with isotype control antibody. Background staining was controlled by labelled isotype controls (BD Biosciences, Caltag and Serotec) and fluorescence minus one (FMO). The results represent the percentage of positively stained cells in the total cell population exceeding the background staining signal. To analyse the functional migration activity of the peritoneal exudate cells towards recombinant KC in the presence or absence of an anti-KC antibody, a 96-well Neuroprobe ChemoTx Chemotaxis plate (Receptor Technologies, Adderbury, UK) with 5 µm pore polycarbonate filters was used, as described previously [21]. Peritoneal exudates from wild-type FVB/N mice were obtained by peritoneal lavage 12 h post-4% thioglycollate injection, and resuspended at a concentration of 8 × 106 cells/ml in serum-free RPMI-1640 media.