When babies take their first breath, the cells of their lungs and airways must be ready for a sudden influx of oxygen and airborne pathogens not encountered during intrauterine life.
But babies born prematurely are not quite ready for the challenge, and they are more susceptible to lung damage because the cells that line their upper respiratory tract (nose, throat, trachea), and form the first line of defense to the baby’s new environment, are not yet fully developed.
A new study from researchers at Columbia University Vagelos College of Physicians and Surgeons now finds that premature birth also impairs the stem cells in the babies’ upper airways, which may contribute to further respiratory complications.
Such cells have not been studied extensively before, because obtaining the cells required invasive intubation or biopsy.
Instead, a team led by Wellington Cardoso, MD, PhD, professor of medicine and genetics & development at Columbia University Vagelos College of Physicians and Surgeons, used a soft thin tube to gently collect cells, including stem cells, from the fluid in the upper air passages of babies. The procedure is routinely used to clear a baby’s respiratory passages during the first minutes of life, but the fluid is normally discarded.
“Stem cells from premature infants may be less able to withstand the physiological demands of their environment.”
The researchers grew the stem cells in cell culture and watched how the upper respiratory epithelial cells created by the stem cells behaved at different stages, comparing cells from premature and mature babies.
Cells from premature infants, the researchers discovered, are defective in their quality control systems, and are unable to ramp up oxygen consumption and adequately protect the upper respiratory tract when under stress.
“Stem cells from premature infants may be less able to withstand the physiological demands of their environment,” Cardoso says.
The study highlights the importance of carefully weighing the benefits and risks of all necessary life-supporting measures in neonatal intensive care units.
“It may be best to prevent prolonged exposure to measures such as mechanical ventilation and oxygen therapy by minimizing the duration of intubation and supplemental oxygen,” Cardoso suggests.
Continued study of upper respiratory tract stem cells has the potential to help researchers better understand why preterm infants develop respiratory diseases and how to prevent and treat them.
The paper is titled “Prematurity alters the progenitor cell program of the upper respiratory tract of neonates,” and was published in Scientific Reports.
The authors are: Jessica E. Shui (Massachusetts General Hospital), Wei Wang (Massachusetts General Hospital), Helu Liu (Columbia), Anna Stepanova (Columbia), Grace Liao (Columbia), Jun Qian (Columbia), Xingbin Ai (Massachusetts General Hospital), Vadim Ten (Columbia), Jining Lu (National Institutes of Health), and Wellington V. Cardoso (Columbia).
The study was funded by the National Institutes of Health (grants R35-HL135834-01 and T32 AI007531-20).
The authors declare no competing interests.