Early MΦ recruitment to PAG-induced cutaneous granulomas is MC dependent.

The absence of MCs in Kit^W/Kit^W-vmice results in impaired recruitment of MΦ to early CGs developing at sites of subcutaneous delivery of PAG. (A) Time course of MΦ recruitment to CGs after PAG injection inKit^+/+ andKit^W/Kit^W-v mice. Data were pooled from 8 or more mice per genotype and time point–tested in at least 4 independent experiments. (B) Migration of MΦ to granulomas inKit^W/Kit^W-v mice 12 hours after induction is repaired by reconstitution of the dermis with connective tissue–type MCs obtained from Kit^+/+ mice. Data were pooled from 8 or more mice per genotype in 2 independent experiments. Data in panels A and B are shown as means ± SEMs (× 10⁶ cells/granuloma). In 1A and 1B, *P < .05, **P < .005, ***P < .001. (C) Characteristic surface staining with anti–MΦ F4/80 and anti–PMN 7/4 mAb of leukocytes recovered from 24- and 72-hour-old granulomas of normal Kit^+/+ mice revealed 2 distinct populations, namely PMNs (7/4⁺) and MΦ (F4/80⁺). Numbers reflect F4/80⁺/7/4⁻ cells and 7/4⁺/F4/80⁻ cells in percent of total cells. One experiment representative of at least 8 independent analyses is shown.