Figure 4.

Splenic CD4⁺ T cells mediate the protective effect of US. (A) US does not prevent IRI in mice deficient of functional T and B lymphocytes (Rag1^−/−). n=4–11. (B) Reconstitution of Rag1^−/− mice with 0.5–2×10⁶ wild-type CD4⁺ T cells (intravenously) 10 days before US restores the protective effect of US in mice challenged with IRI. n=5–7. (C) Splenectomy (7 days before T cell administration) removes the restoration of US protection in Rag1^−/− mice receiving CD4⁺ T cells. (D) Representative H&E image of mice from C. n=4–5. *P=0.003, **P<0.001, ***P=0.002. Scale bars, 100 μm in low-power image, 50 μm in the inset. Data presented as mean ± SEM. SPLX, splenectomized.