Research Paper Volume 12, Issue 18 pp 18396—18414

Figure 5. Exogenous IL-21 promotes inflammatory infiltration in the allograft. C57BL/6 mice received renal allografts from Balb/c mice. Kidney recipients were injected recombinant murine IL-21 (10 μg in 100 μL PBS; n = 9) or 100 μL PBS (n = 7) in the tail vein on days 0, 2, 4, and 6 after transplantation (A). Blank control (n = 3) of mice without transplantation received tail vein injection of PBS simultaneously. All animals were sacrificed 7 days post-transplantation. Histologic evaluation of kidney allografts from Control, KT, and IL-21+KT recipients on day 7 post-transplantation stained with (B) H&E, PAS, and Masson’s stains (scale bar: 100μm). Levels of (C) IFN-γ and TNF, (D) IL-21, IL-2, and IL-4, (E) IL-10, IL-6, and IL-17 in the transplanted kidney of KT subgroups and primary kidney of Control are shown. Values represent mean (±SEM). *P < 0.05, **P < 0.01, and ***P < 0.001. H&E, hematoxylin and eosin; IL, interleukin; PAS, periodic acid–Schiff; PBS, phosphate-buffered saline; KT, kidney transplant; SEM, standard error of the mean.