Figure 12

Figure 12

Partial apex resection surgery at 0 days and heart explanted at 5D PO (A–C)—(A) Gross necropsy heart obtained five days post-operation (5D PO) from piglet #004. Note partially filled surgical defect (blue arrow) (Scale bar = 1 cm). (B) Hematoxylin and Eosin (H & E) histology (piglet #004) reveals a densely packed population of streaming cells in register with peripheral myocardium and with similar slightly larger elongate often plump nuclei (Scale bar = 20 μm). (C) H & E histology (piglet #004) of the marginal zone of proliferative cells has a mitotic figure of a cell identifiable as a cardiomyocyte based on straplike morphology, eosinophilic cytoplasm, and cross striations (black arrows) (Scale bar = 20 μm). Partial apex resection surgery at 0 days and heart explanted at 5D PO (D–F)—(D) Gross necropsy heart obtained five days post-operation (5D PO) from piglet #015. Note partially filled surgical defect (blue arrow) (Scale bar = 1 cm). (E) H & E histology (piglet #015) reveals a population of similar streaming elongate cells with elongate nuclei. (F) Masson’s trichrome stain (piglet #015) reveals a moderate intervening collagenous matrix.