摘要
Microanatomy of the vast majority of human organs at birth is characterized by marked differences as compared toadult organs, regarding their architecture and the cell types detectable at histology. In preterm neonates, thesedifferences are even more evident, due to the lower level of organ maturation and to ongoing cell differentiation.One of the most remarkable finding in preterm tissues is the presence of huge amounts of stem/progenitor cells inmultiple organs, including kidney, brain, heart, adrenals, and lungs. In other organs, such as liver, the completelydifferent burden of cell types in preterm infants is mainly related to the different function of the liver duringgestation, mainly focused on hematopoiesis, a function that is taken by bone marrow after birth. Our preliminarystudies showed that the antigens expressed by stem/progenitors differ significantly from one organ to the next.Moreover, within each developing human tissue, reactivity for different stem cell markers also changes duringgestation, according with the multiple differentiation steps encountered by each progenitor during development. Abetter knowledge of stem/progenitor cells of preterms will allow neonatologists to boost preterm organmaturation, favoring the differentiation of the multiple cells types that characterize each organ in at term neonates.
