Circulating soluble fms-like tyrosine kinase-1 and placental growth factor from 10 to 40 weeks' pregnancy in normotensive women.

INTRODUCTION: Circulating soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) are potential markers for preeclampsia. The objective was to construct and analyse the reference ranges of serum levels of sFlt-1 and PlGF throughout the course of pregnancy in low-risk Thai pregnant women. METHODS: We enrolled 110 low-risk, Thai women singleton pregnancy from 10 to 40 gestational weeks. Serum concentrations of sFlt-1 and PlGF were measured with an automated assay. The reference ranges of serum levels of sFlt-1, PlGF and sFlt-1/PlGF ratio were constructed and assessed for possible correlations with gestational age, maternal factors [age, parity, tobacco use, artificial reproductive technologies (ARTS) and body mass index (BMI)], and pregnancy outcomes (gestational age at delivery, development of preeclampsia, neonatal birth weight and placental weight). RESULTS: None of the subjects developed preeclampsia. Serum sFlt-1 concentrations significantly elevated from 20 to 40 gestational weeks (P=0.003). Significant elevation and dropping of serum PlGF levels and sFlt-1/PlGF ratios were observed at 10 to 29 and 30 to 40 weeks of gestation, respectively (P<0.001). There was an inversed correlation between serum PlGF levels at 20 to 29 gestational weeks and neonatal birth weights (r=-0.48, P<0.05). There were no associations between serum levels of sFlt-1, PlGF, or sFlt-1/PlGF ratios and maternal BMI, gestational age at delivery, or placental weight (P>0.05). Effects from parity, smoking and ARTS were inconclusive. CONCLUSION: Robust change of serum PlGF levels suggests for its broader clinical application compared to sFlt-1. Prediction of preeclampsia using serum analytes may be gestational period specific.

Lymphocyte and NK cell subpopulations in HIV seronegative Thais.

Lymphocyte subpopulations, i.e. T, B and natural killer (NK) cells including NK cell subsets which express CD16 molecules (with or without co-expression of CD56 molecules) and NK cell subsets which express CD56 molecules (with or without co-expression of CD16 molecules) were enumerated by two color-flow cytometry in a total of 125 HIV seronegative Thai adults. The study demonstrated relatively low CD4 counts in the subjects, i.e. 26.3% of them had a CD4 count of less than 500 cells/microl. In contrast, their NK cell counts were relatively high. Statistical analyses of the percentage values showed that females had significantly higher CD3 (total T cells), but lower NK cell counts as compared to males (p < 0.05). Regarding age variation, an increase of 1.1% of CD4 cells per decade was seen. It was roughly estimated that about 86% of NK cells harbored both CD16 and CD56 molecules. Collective data from several studies including the present one suggest that high NK cell counts may be a compensation for low CD4 cell counts in Mongoloid people. Thus, the role of NK cells in the defense cascade against viral infections, especially human immunodeficiency virus infections deserves further investigation.