Biomarkers in human amniotic fluid: a various proteomics approach

Pregnancy is a special time during a woman’s reproductive life as a result of the unique physiology and the presence of a developing fetus. Despite an impressive amount of effort and extensive research over the past century, our knowledge of the development, physiology and pathophysiology of the fetus and its environment remains limited. Thus, study of amniotic fluid (AF) provides unique as well as vital information about the understanding of the biochemistry and physiology of AF and to foresee ways in which the fluid might be used in other diagnostic problems. AF is a complex and dynamic biological fluid that surrounds the fetus in the amniotic cavity which protects the fetus from mechanical as well as thermal shock and also contains nutrients and growth factors that facilitate fetal growth. AF is known to contain large amounts of proteins whose expression profile reflects the genotypic constitution of the fetus and regulates feto-maternal physiological interaction. An intricate balance of proteins is required throughout pregnancy and in cases of pregnancy complications or fetal genetic abnormalities, the balance may be disturbed. So, identification of these changes therefore, may be used for the detection of a particular type of pathology. Proteomics have additional relevance in understanding pathophysiology and the development of molecularly targeted therapeutics. Comparison of normal human AF proteome with that coming from pregnancies carrying fetuses with chromosomal abnormalities facilitated the detection of panels of potential biomarkers for prenatal detection of fetal aneuploidies. The discovery of novel protein biomarkers in either drug development or the study of disease in AF is often hindered by certain particular proteins present at relatively high concentrations. The ability to deplete these proteins specifically, reproducibly and high selectivity is increasingly important in proteomic studies and success in this procedure is leading to an ever-increasing list of low abundant proteins being identified in AF. AF proved to be a promising target for biomarker discovery of pre-mature rupture of amnion, intra-amniotic infection, diseases like DS (Down syndrome) and to distinguish pre-eclampsia from chronic hypertension and normotensic controls.