Terri Shaffer

Background: An increased incidence of adult-onset heart failure is seen in individuals born preterm or affected by fetal growth restriction. An adverse maternal environment is associated with both preterm birth and poor fetal development, and postnatal oxygen therapy is frequently required to sustain oxygenation of vulnerable tissues due to lung immaturity. Methods: Studies using our murine model of maternal inflammation (LPS) and neonatal hyperoxia exposure (O₂) observed pathological changes in cardiac structural proteins and functional analysis with sex dependent differences in pathologies at 10 months of age. Using our previous model, the current investigations tested the hypothesis that early-life perturbations in cardiac structural proteins might predict adult cardiac dysfunction in a sex dependent manner. Results: LPS-exposed females had lower αMHC mRNA and protein at P0 and P7 relative to the saline-exposed females, but these changes did not persist. Male mice exposed to LPS/O₂ had normal expression of αMHC mRNA and protein compared to saline/room air controls though P56, when they dramatically increased. Correlative changes were observed in left ventricular function with a more severe phenotype in the males indicating sex-based differences in cardiac adaptation. Conclusions: Our findings demonstrate that early changes in contractile proteins temporally correlate with deficits in cardiac contractility, with a more severe phenotype in males. Our data suggest that similar findings in humans may predict risk for disease in growth-restricted infants.

Objectives/Hypothesis: Partially decellularized tracheal scaffolds have emerged as a potential solution for long‐segment tracheal defects. These grafts have exhibited regenerative capacity and the preservation of native mechanical properties resulting from the elimination of all highly immunogenic cell types while sparing weakly immunogenic cartilage. With partial decellularization, new considerations must be made about the viability of preserved chondrocytes. In this study, we propose a multimodal approach for quantifying chondrocyte viability for airway tissue engineering.Methods: Tracheal segments (5 mm) were harvested fromC57BL/6 mice, and immediately stored in phosphate‐buffered saline at −20°C (PBS‐20) or biobanked via cryopreservation. Stored and control (fresh) tracheal grafts were implanted as syngeneic tracheal grafts (STG) for 3 months.STGwas scanned with micro‐computed tomography (μCT) in vivo.STGsubjected to different conditions (fresh,PBS‐20, or biobanked) were characterized with live/dead assay, terminal deoxynucleotidyl transferasedUTPnick end labeling (TUNEL), and von Kossa staining.Results: Live/dead assay detected higher chondrocyte viability in biobanked conditions compared to PBS‐20. TUNEL staining indicated that storage conditions did not alter the proportion of apoptotic cells. Biobanking exhibited a lower calcification area than PBS‐20 in 3‐month post‐implanted grafts. Higher radiographic density (Hounsfield units) measured by μCT correlated with more calcification within the tracheal cartilage.Conclusions: We propose a strategy to assess chondrocyte viability that integrates with vivo imaging and histologic techniques, leveraging their respective strengths and weaknesses. These techniques will support the rational design of partially decellularized tracheal scaffolds.Level of Evidence: N/ALaryngoscope, 133:512–520, 2023