The timed-pregnant baboon animal model can be used for determining the role of soluble vascular endothelial growth factor receptors 1 and 2 during development

Bioavailability of the tumor necrosis factor alpha/regulated on activation, normal T cell expressed and secreted (RANTES) biosystem inside the gestational sac during the pre-immune stages of embryo development

OBJECTIVES

In-vivo studies of the bioavailability of major components of the tumor necrosis factor alpha (TNFα) biosystem inside the gestational sac during embryogenesis have not been reported. We sought to determine the concentration of TNFα, soluble (s) TNFα receptors (sTNFR1, sTNFR2), and RANTES in the primate extraembryonic celomic fluid (ECF).

METHODS

A validated timed-pregnant baboon animal model (N: 10) for experimental research in pregnancy was used to collect paired maternal blood and ECF samples in ongoing pregnancies. The concentrations (pg/dL) of TNFα, sTNFR1, sTNFR2, and RANTES were then determined by ELISA immunoassays.

RESULTS

All animals delivered at term healthy newborns. The differential concentration of TNFα, sTNFR1, sTNFR2, and RANTES between the maternal plasma and the ECF could be determined with ratios for TNFα (5.4), sTNFR2 (1.85) and RANTES (3.59) that contrasted with that of sTNFR1 (0.07), which favored the gestational sac compartment. No significant correlations were noted between maternal plasma and ECF TNFR1, sTNFR2 and RANTES. There was a trend for a correlation between TNFα in maternal plasma and ECF (R=0.74; p=0.07).

CONCLUSIONS

We report the physiological concentrations of TNFα, sTNFR1, sTNFR2, and RANTES in extraembryonic celomic fluid during embryogenesis in primates.

Vascular endothelial growth factor pathway in endometriosis: genetic variants and plasma biomarkers

OBJECTIVE

To study single nucleotide polymorphisms (SNPs) involved in angiogenesis (VEGF, PLGF, VEGFR1, VEGFR2, HIF-1α) and plasma levels of the corresponding proteins (VEGF, PLGF, sVEGFR1, sVEGFR2) in women with and without endometriosis.

DESIGN

Allele frequencies of vascular endothelial growth factor (VEGF) pathway SNPs and plasma levels of the corresponding proteins were investigated in patients with endometriosis and in controls.

SETTING

University hospital.

PATIENT(S)

Samples of DNA from 1,931 Caucasian patients were included (1,109 patients with endometriosis and 822 controls). An additional study group included 973 DNA samples from volunteers, self-reported to be healthy without laparoscopic evaluation.

INTERVENTION(S)

Women who underwent a laparoscopy for subfertility and/or pain and healthy volunteers without laparoscopic evaluation.

MAIN OUTCOME MEASURE(S)

Functional SNPs of the VEGF, VEGFR1, VEGFR2, HIF-1α genes and Hap Map tagging SNPs of the PLGF gene were genotyped by using iPLEX technology on a Sequenom MassArray and TaqMan SNP Genotyping Assay. The VEGF levels were determined in ethylenediaminetetraacetic acid plasma samples by using Bio-Plex Protein Array System. PLGF, sVEGFR1, and sVEGFR2 levels were measured in ethylenediaminetetraacetic acid plasma samples by using ELISA Quantikine kits.

RESULT(S)

A significant association was found between the rs2268613 polymorphism in the PLGF gene and PLGF plasma levels. In all study subjects, women with the AA variant of the rs2268613 PLGF gene had significantly lower PLGF plasma levels (median [interquartile range] 9.36 [8.19-10.43] pg/mL) than those with the AG variant (12.1 [11.81-20.84] pg/mL; P(a)=.0085, P(b)=.04), both before and after multiple testing. Plasma levels of VEGF were elevated in endometriosis patients (especially in minimal-mild endometriosis during the menstrual cycle phase) compared with laparoscopic controls but had a moderate diagnostic performance (area under the curve, 0.73) in this discovery dataset. At a cut-off plasma level of VEGF >3.88 pg/mL, minimal-mild stages of endometriosis were diagnosed with a sensitivity of 74% and a specificity of 80% during the menstrual phase of cycle. The associations between the presence of endometriosis and SNPs in PLGF (rs2268614), HIF-1α (rs11549465), and VEGFR1 (rs9582036) genes lost statistical significance after multiple testing.

CONCLUSION(S)

Genetic variants in the PLGF rs2268613 gene may influence plasma levels of the corresponding protein. Plasma levels of VEGF were elevated in endometriosis patients compared with controls. The associations between the presence of endometriosis and SNPs in PLGF (rs2268614), HIF-1α (rs11549465), and VEGFR1 (rs9582036) genes lost statistical significance after multiple testing.

Periodontitis in pregnant baboons: systemic inflammation and adaptive immune responses and pregnancy outcomes in a baboon model

BACKGROUND/OBJECTIVES

Chronic periodontal infections have been suggested to contribute to the risk of adverse pregnancy outcomes.

MATERIAL AND METHODS

This study describes the relationship of patterns of systemic inflammatory mediators and IgG antibody to 20 oral bacteria in pregnant female baboons (Papio anubis) coupled with clinical features of ligature-induced periodontitis, as risk indicators for adverse pregnancy outcomes. Animals showing a preterm delivery and/or low birth weight newborns, as well as those pregnancies resulting in spontaneous abortion, stillbirth, or fetal demise were tabulated as adverse pregnancy outcomes.

RESULTS

A significantly greater frequency of the periodontitis group neonates had a low birth weight (18.1%; p = 0.008) and decreased gestational age (9.8%). Spontaneous abortion/stillbirth/fetal demise were increased in the periodontitis (8.7%) versus the control group (3.8%) (p = 0.054). The baseline oral clinical presentation of the experimental animals did not relate to the adverse pregnancy outcomes. Animals with the greatest extent/severity of periodontitis progression during the initial ½ of gestation (ie. to mid-pregnancy) had the greatest risk for adverse pregnancy outcomes. Baseline biological parameters indicating historical responses of the animals to periodontal challenge demonstrated individual variation in selected mediators, some of which became more differential during ligature-induced periodontitis. The relationship of clinical parameters to systemic inflammatory responses was consistent with a temporal contribution to adverse pregnancy outcomes in a subset of the animals.

CONCLUSIONS

These results support a link between periodontitis and adverse pregnancy outcomes in the baboons and provide a prospective experimental model for delineating the biologic parameters that contribute to a causal relationship between chronic oral infections and birth events.

Growth hormone-related genes from baboon (Papio hamadryas): Characterization, placental expression and evolutionary aspects

Pregnancy is a complex physiological condition, and the growth hormone (GH)-related hormones produced in the placenta, which emerged during the evolution of primates, are thought to play an important metabolic role in pregnancy that is not yet fully understood. The aim of this study was to identify the genes and transcription products of the GH family in baboon (Papio hamadryas) and to assess these in relation to the evolution of this gene family. GH-related transcripts were amplified using total RNA from placental tissue, by reverse transcription coupled to polymerase chain reaction (RT-PCR). Three different GH-related transcripts were identified in baboon placental tissue, with two encoding chorionic somatomammotropins (CSH) and one the placental variant of GH (GH-2). The CSH transcripts showed some minor allelic variation, and a splice variant of CSH-C that retains its in-frame third intron. Gene sequences for GH-1 (probably representing the GH gene expressed primarily in the pituitary gland), GH-2 and the two CSHs were identified in the baboon genomic database, together with a CSH-related pseudogene. Phylogenetic analysis of the baboon GH-related sequences, together with those of a related Old World monkey, macaque, and ape outgroup (human), showed the equivalence of the genes in baboon and macaque, and revealed evidence for several episodes of rapid adaptive evolution. Many of the substitutions seen during the evolution of these placental proteins have occurred in the receptor-binding sites, especially site 2, contrasting with the strong conservation of the hydrophobic core.