Fetal and neonatal samples of a precursor surfactant protein B inversely related to gestational age

Abstract

BackgroundAlveolar–capillary membrane leaks can increase the amount of surfactant protein B (SP-B) in the bloodstream. The purpose of this study was to measure the concentration of C-proSP-B, a SP-B precursor that includes C-terminal domains, in various body fluids of newborn infants and determine its dependence on gestational age.MethodsC-pro-SPB was measured in amniotic fluid and umbilical cord blood at birth, and in peripheral blood and urine on postnatal day 3 in 137 newborn infants with a median birth weight of 2015 g (range, 550–4475 g) and gestational age of 34 weeks (range, 23–42 weeks).ResultsC-proSP-B levels differed more than 100-fold among samples. The levels (median; interquartile range) were highest in peripheral blood (655.6 ng/mL; 419.0-1467.0 ng/mL) and lowest in urine (3.08 ng/mL; 2.96-3.35 ng/mL). C-proSP-B levels in amniotic fluid (314.9 ng/mL; 192.7–603.6 ng/mL) were approximately half of those in peripheral blood. In cord blood C-proSP-B was slightly lower (589.1 ng/mL; 181.2-1129.0 ng/mL) compared with peripheral blood. C-proSP-B levels significantly increased in all the fluids sampled except urine with decreasing gestational age (p < 0.001).ConclusionsThis novel assay allows for the quantitative measurement of C-proSP-B in blood and amniotic fluid. The dependence of C-proSP-B on gestational age may hamper its use for the detection of alveolar leaks in preterm newborns.

Approaches to Evaluate Lung Inflammation in Translational Research

“…Evaluation of peripheral blood during the course of a study or at autopsy can be useful to monitor systemic inflammatory changes 15 and to corroborate with lung-specific inflammation data. Peripheral blood samples can be used for a complete blood count and to track inflammatory biomarkers such as acute phase proteins, 30 cytokines, 13 and markers of lung injury 31 and as emerging technologies. For instance, use of “liquid biopsies” (analysis of tumor cell by-products from peripheral blood) is an emerging molecular approach in cancer research, 49,101 and this technology is being studied to identify tissue-specific (eg, lung) inflammatory diseases.…”

Experimental study of peripheral-blood pro-surfactant protein B for screening non-small cell lung cancer

“…Our previous studies have shown that Pro-SFTPB often presents in the peripheral blood of immaturely developed children and is associated with many chronic lung diseases, such as respiratory distress syndrome (RDS) [13][14][15][16] , which may cause chronic lung dysfunction in chronic obstructive pulmonary disease (COPD) patients 17 . Mean-while, the abnormal regulation of surfactant protein B in non-small cell lung cancer (NSCLC) may cause its overexpression of Pro-SFTPB.…”