Fig. 4: BMSC expression of pMCUwt protects against LPS injury.

a MCU immunoblots in AT2 mitochondria derived from mice given indicated intranasal instillations. BMSCs expressing the wild-type MCU plasmid (BM-MCUwt) were intranasally instilled 4 h after nonlethal LPS instillations. Lungs were excised and AT2 isolated 24 h after LPS (1 mg/kg) instillations. Bars show densitometry. Bars: mean ± SEM. n = 3 lungs for each group. Groups were compared using one-way ANOVA with Bonferroni correction. n.s., not significant. b, c Group data are for AT2 cytosolic (cCa²⁺) and mitochondrial (mCa²⁺) calcium (b) and surfactant secretion (c, loss of LTR fluorescence) responses following hyperinflation. Sequence of intranasal instillations is indicated. All determinations were carried out 24 h after the first instillation. BM-MCUmt, BMSCs expressing a mutant MCU. Bars: mean ± SEM. n = 4 lungs each bar. Groups were compared using one-way ANOVA with Bonferroni correction. n.s., not significant. In c, p-values are for two-tailed Student’s t-test, n.s., not significant. d Bars quantify the alveolar inflammatory response to indicated instillations as quantified by neutrophil counts in the bronchioalveolar lavage (BAL) obtained 24 h after the first instillation. Bars: mean ± SEM. n = 4 lungs each bar. Groups were compared using one-way ANOVA with Bonferroni correction. n.s., not significant. e Mouse survival after instillations of lethal LPS (10 mg/kg) in Swiss Webster mice. The groups are: LPS alone (red), LPS followed 4 h later with instillation of BM-MCUwt (green) or BM-MCUmt (black). N = 10 each group, *p = 0.038 versus LPS by Log-Rank test.