Measurement of human surfactant protein-B turnover in vivo from tracheal aspirates using targeted proteomics.
Anal Chem
; 82(6): 2561-7, 2010 Mar 15.
Article
em En
| MEDLINE
| ID: mdl-20178338
ABSTRACT
We describe a method to measure protein synthesis and catabolism in humans without prior purification and use the method to measure the turnover of surfactant protein-B (SP-B). SP-B, a lung-specific, hydrophobic protein essential for fetal-neonatal respiratory transition, is present in only picomolar quantities in tracheal aspirate samples and difficult to isolate for dynamic turnover studies using traditional in vivo tracer techniques. Using infusion of [5,5,5-(2)H(3)] leucine and a targeted proteomics method, we measured both the quantity and kinetics of SP-B tryptic peptides in tracheal aspirate samples of symptomatic newborn infants. The fractional synthetic rate (FSR) of SP-B measured using the most abundant proteolytic fragment, a 10 amino acid peptide from the carboxy-terminus of proSP-B (SPTGEWLPR), from the circulating leucine pool was 0.035 +/- 0.005 h(-1), and the fractional catabolic rate was 0.044 +/- 0.003 h(-1). This technique permits high-throughput and sensitive measurement of turnover of low abundance proteins with minimal sample preparation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Traqueia
/
Proteína B Associada a Surfactante Pulmonar
/
Proteômica
Tipo de estudo:
Diagnostic_studies
/
Evaluation_studies
Limite:
Humans
/
Newborn
Idioma:
En
Revista:
Anal Chem
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos