The role of recipient mast cells in acute and chronic cardiac allograft rejection in C57BL/6-Kit^W-sh/W-sh mice

(A) Survival of cardiac allografts in wild-type (Kit^+/+) mice (filled circles; n = 8) or genetically mast cell-deficient (Kit^W-sh/W-sh) mice (open circles; n = 8) during acute rejection. (B) Survival of cardiac allografts from donor Kit^+/+ mice (filled circles; n = 6) or mast cell-deficient Kit^W-sh/W-sh mice (open circles; n = 6) transplanted into FVB recipient mice during acute rejection. (C) Histology of cardiac allografts transplanted into Kit^+/+ or mast cell-deficient Kit^W-sh/W-sh mice at 5 days after transplantation. The bar = 100 μm; hematoxylin and eosin stain; original magnification × 100. (D) Parenchymal rejection (PR) scores at 5 days after transplantation. Data are the mean and standard error of the mean for 8 mice per group. NS, not significant (p > 0.05).

(A) Immunohistochemical staining of CD4⁺, CD8⁺, and CD11b⁺ cells in allografts at 5 days after transplantation during acute rejection. The bar = 100 μm; original magnification ×400. (B) Quantitative analysis of CD4⁺, CD8⁺, and CD11b⁺ cells. Data are the mean and standard error of the mean of values derived from an analysis of 20 fields.

Expression of adhesion molecules, cytokines, and the chemokine monocyte chemotactic protein-1 (MCP-1) is shown during acute rejection in allografts transplanted into Kit^+/+ mice (filled bars; n = 6) or Kit^W-sh/W-sh mice (open bars; n = 6). *p < 0.05 vs values for Kit^+/+ mice. Data show the mean and standard error of the mean in each group. ICAM, intracellular cell adhesion molecule; IFN-γ, interferon-γ; IL, interleukin; VCAM, vascular cell adhesion molecule.

(A) Baseline mast cell numbers in non-transplanted donor hearts. (B) Mast cell numbers/mm² detected in Bm12 allografts transplanted into Bm12 mice (isograft controls). (C) Bm12 allografts transplanted into C57BL/6-Kit^W-sh/W-sh mice. (D) Mast cell numbers/mm² in allografts from C57BL/6-Kit^+/+ recipients 52 days after transplantation. The error bar shows the standard error of the mean.

(A) The graft beating scores of allografts in Kit^+/+ mice (filled squares; n = 8) and Kit^W-sh/W-sh mice (open circles; n = 8) after cardiac transplantation in the chronic rejection model, consisting of an major histocompatibility complex class II mismatch. (B) Elastic Van Gieson-stained representative sections of cardiac allografts undergoing chronic rejection 52 days after transplantation into Kit^+/+ or Kit^W-sh/W-sh mice. Original magnification ×400. (C) Data from morphometric assessment of luminal occlusion, intima/media (I/M) ratio, and diseased vessels in sections like those shown in Panel A. Data are the mean and standard error of the mean for 8 mice per group.

(A) Representative sections of cardiac allografts undergoing chronic rejection 52 days after transplantation into Kit^+/+ or Kit^W-sh/W-sh mice. The bar = 100 μm; hematoxylin and eosin stain; original magnification ×100. (B) Parenchymal rejection (PR) and fibrotic scores in sections like those shown in Panel A. Data are the mean and standard error of the mean (SEM) from 8 mice per group. (C) Quantitative analysis of CD4⁺, CD8⁺, and CD11b⁺ cells. Data are the mean and SEM of values derived from an analysis of 20 fields with 6 mice per group.