Injury to LC during an acute GVHR. Experimental acute GVHD was induced by transfer of 60 × 10⁶ parental B6.CD45.1 splenocytes to unirradiated B6D2F₁ mice (▪), whereas B6D2F₁ mice that received syngeneic transplants (□) served as controls. (A) Determinations of serum testosterone by radioimmunoassay were done at the Institute for Reproductive Medicine (University of Muenster, Muenster, Germany). The graph represents pooled data from 8 (non-GVHD) and 7 (GVHD) mice, respectively, that were analyzed between 2 and 3 weeks after transplantation in 1 independent experiment. Three experiments were performed, with similar results. Medians are represented by horizontal bars within the quartile boxes, the ranges are given by vertical bars. Mann-Whitney U test, P = .05 syngeneic versus allogeneic transplantation. (B-E) Paraffin sections (6 μm) of testicular tissue were analyzed for LC-specific Cy p450scc expression (in red color) at 3 weeks after transplantation in mice without (B,D) and with GVHD (C,E). The nuclear counterstain (hematoxylin) is displayed in panels B and C for both groups in blue color. The horizontal bars represent 100 μm.A20×/0.5 HC-PL Fluotar objective lens was used (Leica). Photographs were taken with a KY-F55B-type JVC camera. (F) Sections from mice without and with GVHD were stained with antibody to Cy p450scc and were subjected to computer-aided quantitative morphometric analysis of the LC compartment. The LC volume density (%) was calculated from 5 random high-powered microscope fields per tissue section, with 5 sections per testis (serial sections separated by 30 μm; total of 25 fields per mouse). The figure depicts representative data (mean ± SD) from 1 (of 3) independent experiments, with 5 mice analyzed for each group. B6D2F₁ mice infused with syngeneic (□) or allogeneic (▪) donor T cells. Unpaired t test, P < .005 syngeneic versus allogeneic transplantation. Untransplanted, naive B6D2F₁ mice served as additional controls (▨).