Abstract
The surfactant complex, thanks to its multiple actions including decrease of surface-tension and antimicrobial activity, plays a fundamental role in newborn survival, lowering the risk of respiratory distress syndrome. The aim of this work was to determine if the synthesis of two surfactant proteins (SP), SPA and pro-SPB, shows some inter-individual variability during lung development in the intrauterine life. Immunoreactivity for SPA and pro-SPB was investigated in the lungs of 40 subjects, including 15 fetuses, ranging from 14 to 22 weeks of gestation, and 25 neonates, from 24 to 41 weeks. Lung samples were formalin fixed, paraffin-embedded and routinely processed. SPA and pro-SPB were detected utilizing commercial antibodies. A semi-quantitative grading system (1 to 4) was applied, based on the number of reactive cells and the intensity of immunostaining. Surfactant protein immunostaining was found in three compartments: bronchi, bronchioles and alveoli, starting from 14 weeks of gestation in the bronchial epithelium and from the 21st week in the alveolar spaces. Differences were found regarding SPA and pro-SPB expression in the vast majority of subjects: in some lungs, SPA was more expressed whereas in others pro-SPB showed an higher degree of immunoreactivity. The expression of both surfactant proteins was not strictly correlated with gestational age. Whereas the highest levels of reactivity were detected in at term neonates, on the other hand one case with grade 3 was detected at 22 weeks and one negative case for both proteins was observed at 31 weeks. Our data clearly show a marked inter-individual variability regarding the production of SPA and pro-SPB and suggest the existence of other epigenetic factors, acting during gestation, that might influence surfactant production and, consequently, the survival potential of neonates at birth.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.