Characterization of TGF-β production from the cellular infiltrate in sclerodermatous skin. (A) Balb/c recipient mice underwent transplantation with 12.5 × 10⁷ splenocytes from G-CSF-treated B10.D2 donors, as described in “Materials and methods.” Frozen sections of skin were obtained 6 weeks after SCT and were stained by immunohistochemistry with CD3 and CD11b antibodies, as outlined in “Materials and methods.” (B) Splenocytes from G-CSF-treated B10.D2 donors were transplanted into Balb/c recipients (n = 6), as described in panel A. Six weeks after SCT, animals were humanely killed and dorsal skin was prepared for FACS analysis, as described in “Materials and methods.” Percentages of CD3⁺ and CD11b⁺ cells were assessed in the CD45.2⁺ population. Data are expressed as mean ± SE (^*P < .05). (C) CD3⁺ and CD11b⁺ cells obtained by skin digestion were FACS sorted and assayed for TGF-β by real-time PCR, as described in “Materials and methods.” Data are expressed as mean ± SE from triplicate samples (^*P < .05).