Ears, tails, spleens, and skin-draining lymph nodes were harvested at the indicated times. Spleens were disrupted, and the red blood cells were lysed with RBC lysis buffer. Ear and tail skin were incubated in skin digest medium [RPMI containing 0.5% deoxyribonuclease (DNase) I (Sigma-Aldrich, St Louis, MO) and liberase TL enzyme blend (0.5 mg/ml) (Roche, Indianapolis, IN)] and processed with a medimachine (BD Biosciences, San Jose, CA) as described previously (Harris et al, 2012 (link)). For separation of the dermis and epidermis, tail skin samples were incubated with dispase (2.4 U/ml) (Roche, Indianapolis, IN) for 1 hour at 37°C. Epidermis was removed and mechanically disrupted with 70-μm cell strainers, and dermis samples were incubated with collagenase IV (1 mg/ml) with DNase I (0.5 mg/ml) (Sigma-Aldrich, St Louis, MO) for 1 hour at 37°C on a shaker. Cells were filtered through a 70-μm mesh before analysis. The following antibodies were obtained from BioLegend (San Diego, CA): mouse (CD8β, CD45.2, CD90.1, and Fc block). The data were collected and analyzed with a BD LSR II flow cytometer (BD Biosciences, San Jose, CA) and FlowJo (Tree Star Inc., Ashland, OR).