The evolution of blood protein profiles of extremely preterm infants after birth

Preterm birth is the leading cause of neonatal mortality and morbidity. Even so, the etiology is multifactorial and poorly understood. Blood protein profiling during the first months of life in preterm infants can shed light on the role of early extrauterine development and provide an increased understanding of maturation after extremely preterm birth and the underlying mechanisms of prematurity-related disorders. Using proximity extension assays, we measured 538 unique proteins in 1335 longitudinal serum samples from birth to 40 weeks postmenstrual age in 182 extremely preterm infants. The results reveal evident predestined protein evolution patterns common for all included infants. The degree of immaturity seems most influential on protein expression at two weeks postnatal age. Further on, most variations in protein expression were associated with postnatal age rather than any other factor. The study contributes valuable insight into the postnatal development of extremely premature infants.