Plasma levels of osteopontin from birth to adulthood.

Abstract

Osteopontin (OPN) has been investigated as a biomarker for cancer and nonmalignant diseases during the last decades. Data about OPN as a potential biomarker in childhood diseases are still sparse, and reference values are not available in children. We aimed to establish reference values for children from birth to young adulthood and evaluate whether there are age-, gender-, and weight-specific differences. Umbilical cord blood and blood plasma samples of 117 children were collected in the Children's Hospital of Saarland University in Homburg/Saar. OPN levels were measured by ELISA, and statistical analysis was performed using SPSS software. Neonates, infants, toddlers, young children, adolescents, and adults were divided into the following six age groups: newborns (birth), infancy and toddlers (0-24 months), early childhood (3-6 years), middle childhood (7-11 years), adolescence (12-18 years), and adults (>18 years). Highest blood OPN levels were found in the group of 0-1 years of age. OPN blood levels declined significantly with age (Spearman r=-0.874; P<0.001). Our work is the first prospective and systematic study analyzing OPN cord blood and blood plasma levels in children of all ages. It is the first study yielding reference values for different age groups from birth to young adulthood. Our data give insight on how OPN in umbilical cord blood and OPN in blood plasma are physiologically influenced during childhood development and growth with high OPN levels after birth and a constant age-related decline until the age of 14, when OPN levels reach similar values to those measured in adults.