R-848 leads to increased rolling of PBMCs on endothelia. CFSE-stained spleen cells were adoptively transferred to mice. Then the animals were subjected to intravital imaging of green cells within a blood vessel above the inguinal lymph node. After observation of the normal flow of cells, animals received injections of PBS followed by R-848 intraperitoneally. Then the observation was continued within the same vessel until 1 or 2 hours after each injection. Shown is the percentage of cells exhibiting reduced speed or rolling in the blood vessels between 40 to 60 minutes after injection of PBS or 88 ± 26 minutes after injection of R-848. Data represent the mean ± SD for 6 experiments performed with R-848 (5 experiments for PBS).