MTOR and bronchiolitis obliterans syndrome: mTOR phosphorylation on serine 2448, a specific marker of mTORC1 formation, was also significantly decreased in the heart of BO mice (Control (n = 6) vs. BO (n = 6): 100 ± 8 vs. 64 ± 16%, P = 9.8 x 10−5 by one-way ANOVA followed by the Tukey-Kramer post hoc test).