Galectin-7 in Cardiac Allografts in Mice: Increased Expression Compared With Isografts and Localization in Infiltrating Lymphocytes and Vascular Endothelial Cells

We sought to identify elevated expression of galectin-7, a T-cell binding protein, in renal allograft recipients undergoing acute rejection episodes. Allografts and isografts were examined immunohistologically and using quantitative Western blot analysis for galectin-7 protein. The expression of galectin-7 in T lymphocytes from draining lymph nodes in the recipient mice was examined using flow cytometry. We observed galectin-7 to gradually increase with time in the allografts to be significantly higher than that in isografts at days 3, 5, and 7 postoperative: 0.85 +/- 0.03 versus 0.69 +/- 0.05; 1.15 +/- 0.11 versus 0.81 +/- 0.02; and 2.02 +/- 0.12 versus 0.81 +/- 0.05 (P < .05). The majority of galectin-7 was located in the infiltrating lymphocytes and vascular endothelial cells. Furthermore, the percentage of CD4+galectin-7+ and CD8+galectin-7+ T cells from draining lymph nodes in the allograft group was higher than that in the isograft group: 28.0 +/- 1.0% versus 1.2 +/- 0.2%; and 12.4 +/- 0.8% versus 0.4 +/- 0.1% (P < .01). In conclusion, galectin-7 relates to acute allograft rejection and T-cell responses possibly as an accelerant.