FIGURE 7.

Neutrophil chemotaxis and recruitment are not affected in Ptpn22^−/− mice. (A–D) Neutrophils isolated from bone marrows of Ptpn22^−/− [knockout (ko)] and matched WT control mice were allowed to chemotax toward 10 nM MIP2 in Dunn chambers. Cell migration was monitored by time-lapse imaging, and individual cells were tracked using a cell tracking plug-in into Image J. (A) Tracks obtained in experiments carried out with three separate preparations of bone marrow–derived neutrophils analyzed were pooled for these spider plots. The source of chemoattractant is indicated (*). (B–D) The coordinates for the tracks shown in (A) were analyzed using statistics features of the Ibidi chemotaxis plug-in into Image J, as detailed in Materials and Methods. Parameters presented (means ± SEM) are directionality (B), total accumulated (C), and Euclidian distances (D); differences were not statistically significant. (E) Ptpn22^−/− (ko) and control (wt) neutrophils were allowed to migrate toward indicated concentrations of MIP2 in Transwells supporting a monolayer of TNF-α–stimulated mouse endothelial cells. Data (means ± SEM) expressed as percentage of control cells migrating toward 1 nM MIP2 from two pooled experiments carried out with separately prepared neutrophils are presented. (F) Peritonitis was induced in Ptpn22^−/− (ko) and WT control mice by injection of thioglycollate-containing broth. Peritoneal flushes were analyzed to enumerate numbers (means ± SEM) of peritoneal neutrophils. A representative experiment performed with six controls and five Ptpn22^−/− mice is shown. Differences were not statistically significant.