Proteomic profiling of amniotic fluid in preterm labor using two-dimensional liquid separation and mass spectrometry
- 1 January 2008
- journal article
- research article
- Published by Informa UK Limited in The Journal of Maternal-Fetal & Neonatal Medicine
- Vol. 21 (10), 697-713
- https://doi.org/10.1080/14767050802053289
Abstract
Objective. Simultaneous analysis of the protein composition of biological fluids is now possible. Such an approach can be used to identify biological markers of disease and to understand the pathophysiology of disorders that have eluded classification, diagnosis, and treatment. The purpose of this study was to analyze the differences in protein composition of the amniotic fluid of patients in preterm labor. Study design. Amniotic fluid was obtained by amniocentesis from three groups of women with preterm labor and intact membranes: (1) women without intra-amniotic infection/inflammation (IAI) who delivered at term, (2) women without IAI who delivered a preterm neonate, and (3) women with IAI. Intra-amniotic infection was defined as a positive amniotic fluid culture for microorganisms. Intra-amniotic inflammation was defined as an elevated amniotic fluid interleukin (IL)-6 (≥2.3 ng/mL). Two-dimensional (2D) chromatography was used for analysis. The first dimension separated proteins by isoelectric point, while the second, by the degree of hydrophobicity. 2D protein maps were generated using different experimental conditions (reducing agents as well as protein concentration). The maps were used to discern subsets of isoelectric point/hydrophobicity containing differentially expressed proteins. Protein identification of differentially expressed fractions was conducted with mass spectrometry. Enzyme-linked immunosorbent assays (ELISA) as well as surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS)-based on-chip antibody capture immunoassays were also used for confirmation of a specific protein that was differentially expressed. Results. (1) Amniotic fluid protein composition can be analyzed using a combination of 2D liquid chromatography and mass spectrometry for the identification of proteins differentially expressed in patients in preterm labor. (2) While total insulin-like growth factor-binding protein-1 (IGFBP-1) concentration did not change, IGFBP-1 fragments at about 13.5 kDa were present in patients with IAI. (3) Proteins that were over-expressed in group 1 included von Ebner gland protein precursor, IL-7 precursor, apolipoprotein A1, tropomyosin sk1 (TPMsk1) fragment, ribosomal protein S6 kinase alpha-3, and alpha-1-microglobulin/bikunin precursor (AMBP). (4) Proteins that were over-expressed in group 3 included fibrinopeptide B, transferrin, major histocompatibility complex (MHC) class 1 chain-related A antigen fragment, transcription elongation factor A, sex-determining region Y (SRY) box 5 protein, Down syndrome critical region 2 protein (DSCR2), and human peptide 8 (HP8). (5) One protein, retinol-binding protein, was over-expressed in women who delivered preterm, regardless of the presence of IAI. Conclusions. A combination of techniques involving 2D chromatography, mass spectrometry, and immunoassays allows identification of proteins that are differentially regulated in the amniotic fluid of patients with preterm labor. Specifically, the amount of the IGFBP-1 fragments at approximately 13.5 kDa was found to be increased in patients with IAI, while the amount of the intact form of IGFBP-1 was decreased.Keywords
This publication has 91 references indexed in Scilit:
- Evidence supporting proteolytic cleavage of insulin-like growth factor binding protein-1 (IGFBP-1) protein in amniotic fluidjpme, 2008
- Proteomic Analysis of Cervical−Vaginal Fluid: Identification of Novel Biomarkers for Detection of Intra-amniotic InfectionJournal of Proteome Research, 2006
- The end of “naïve reductionism”: rise of systems biology or renaissance of physiology?American Journal of Physiology-Cell Physiology, 2005
- Molecular and cellular characterization of the Down syndrome critical region protein 2Biochemical and Biophysical Research Communications, 2005
- Protein analysis on a proteomic scaleNature, 2003
- Down Syndrome Critical Region Gene 2: Expression during Mouse Development and in Human Cell Lines Indicates a Function Related to Cell ProliferationBiochemical and Biophysical Research Communications, 2000
- Lipopolysaccharides Induce p8 mRNA Expression in Vivo and in VitroBiochemical and Biophysical Research Communications, 1999
- Identification and Characterization of a New Gene from Human Chromosome 21 between Markers D21S343 and D21S268 Encoding a Leucine-Rich ProteinBiochemical and Biophysical Research Communications, 1998
- Augmentation and stable expression of a novel transcription factor SII in CD4-positive cells on infection with human immunodeficiency virus type-1(HIV-1)Biochemical and Biophysical Research Communications, 1988
- Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4Nature, 1970