Perinatal plasma monocyte chemotactic protein-1 concentrations in intrauterine growth restriction

Modeling the Progression of Placental Transport from Early- to Late-Stage Pregnancy by Tuning Trophoblast Differentiation and Vascularization

The early-stage placental barrier is characterized by a lack of fetal circulation and by a thick trophoblastic barrier, whereas the later-stage placenta consists of vascularized chorionic villi encased in a thin, differentiated trophoblast layer, ideal for nutrient transport. In this work, predictive models of early- and late-stage placental transport are created using blastocyst-derived placental stem cells (PSCs) by modulating PSC differentiation and model vascularization. PSC differentiation results in a thinner, fused trophoblast layer, as well as an increase in human chorionic gonadotropin secretion, barrier permeability, and secretion of certain inflammatory cytokines, which are consistent with in vivo findings. Further, gene expression confirms this shift toward a differentiated trophoblast subtype. Vascularization results in a molecule type- and size-dependent change in dextran and insulin permeability. These results demonstrate that trophoblast differentiation and vascularization have critical effects on placental barrier permeability and that this model can be used as a predictive measure to assess fetal toxicity of xenobiotic substances at different stages of pregnancy.

Associations between maternal inflammation during pregnancy and infant birth outcomes in the Seychelles Child Development Study

PROBLEM

Markers of maternal inflammation may determine infant birth outcomes.

METHOD OF STUDY

Maternal serum samples were collected at 28 weeks gestation (n = 1418) in the Seychelles Child Development Study Nutrition Cohort 2 and analyzed for immune markers by MSD multiplex assay, including cytokines from the Th1 (IFN-γ, IL-1β, IL-2 and TNF-α) and Th2 (IL-4, IL-5, IL-10) subsets, with IL-6, MCP-1, TARC, sFlt-1 and VEGF-D. Associations of log-transformed immune markers with birthweight, length, head circumference and gestational age were assessed by multiple linear regression models, which were adjusted for maternal age, BMI, parity, child sex, gestational age and socioeconomic status.

RESULTS

Neither total Th1, Th2 nor Th1:Th2 were significantly associated with any birth outcome. However, the angiogenesis marker VEGF-D was predictive of a lower birthweight, (β = -0.058, P = 0.017) and birth length (β = -0.088, P = 0.001) after adjusting for covariates. Higher concentrations of CRP were predictive of a lower birthweight (β = -0.057, P = 0.023) and IL-2 (β = 0.073, P = 0.009) and the chemokine MCP-1 (β = 0.067, P = 0.016) were predictive of a longer gestational age.

CONCLUSIONS

In our cohort of healthy pregnant women, we found no evidence for associations between the Th1 or Th2 inflammatory markers with birth outcomes. However, VEGF-D and CRP appear to predict lower birthweight and IL-2 and MCP-1 a longer gestation. Greater understanding is required of the variation in these immune markers at different gestational stages, as well as the factors which may regulate their balance in healthy pregnancy. n = 233.

Chemokine (C-C motif) ligand 25 expressed by trophoblast cells and leukocytes bearing its receptor Ccr9: An alliance during embryo implantation?

PROBLEM

We hypothesized that trophoblast expression of Ccl25 attracts a specific leukocyte cell population to the implantation site for local regulation.

METHOD OF STUDY

Mice blastocysts, ectoplacental cones, and decidua at gestational days 3.5-7.5 were evaluated for Ccl25 and Ccr9 expressions. Peripheral availability and characterization of Ccr9+ leukocytes were determined by flow cytometry. Leukocyte chemotaxis was assessed in the presence of Ccl25 recombinant protein and embryos using antisense oligomers (ODNs) to Ccl25 and Ccr9 neutralizing antibody.

RESULTS

Ccl25 was expressed by embryonic cells, whereas Ccr9 expression was strong at the maternal compartment and in PBMC. Immunolocalization confirmed this expression. In vitro, chemotaxis assays showed that the embryonic Ccl25 signals to Ccr9+ PBMCs. Maternal Ccr9+α4β7+ monocytes switch from an anti-inflammatory phenotype (F4/80+11b+Ly6C-TGF-β+ cells, pre-implantation) to an inflammatory profile (F4/80+11b+Ly6C+TNF-α+ cells, post-implantation).

CONCLUSION

Our data support the establishment of a CCL25/CCR9-axis at the maternal-fetal interface in mice, which may be involved in immune regulatory mechanisms during embryo implantation.

Potential pathways by which maternal second-hand smoke exposure during pregnancy causes full-term low birth weight

It is well documented that maternal exposure to second-hand smoke (SHS) during pregnancy causes low birth weight (LBW), but its mechanism remains unknown. This study explored the potential pathways. We enrolled 195 pregnant women who delivered full-term LBW newborns, and 195 who delivered full-term normal birth weight newborns as the controls. After controlling for maternal age, education level, family income, pre-pregnant body mass index, newborn gender and gestational age, logistic regression analysis revealed that LBW was significantly and positively associated with maternal exposure to SHS during pregnancy, lower placental weight, TNF-α and IL-1β, and that SHS exposure was significantly associated with lower placental weight, TNF-α and IL-1β. Structural equation modelling identified two plausible pathways by which maternal exposure to SHS during pregnancy might cause LBW. First, SHS exposure induced the elevation of TNF-α, which might directly increase the risk of LBW by transmission across the placenta. Second, SHS exposure first increased maternal secretion of IL-1β and TNF-α, which then triggered the secretion of VCAM-1; both TNF-α and VCAM-1 were significantly associated with lower placental weight, thus increasing the risk of LBW. In conclusion, maternal exposure to SHS during pregnancy may lead to LBW through the potential pathways of maternal inflammation and lower placental weight.

Angiogenic and inflammatory biomarkers in midpregnancy and small-for-gestational-age outcomes in Tanzania

OBJECTIVE

We sought to investigate the relationship between a panel of angiogenic and inflammatory biomarkers measured in midpregnancy and small-for-gestational-age (SGA) outcomes in sub-Saharan Africa.

STUDY DESIGN

Concentrations of 18 angiogenic and inflammatory biomarkers were determined in 432 pregnant women in Dar es Salaam, Tanzania, who participated in a trial examining the effect of multivitamins on pregnancy outcomes. Infants falling below the 10th percentile of birthweight for gestational age relative to the applied growth standards were considered SGA. Multivariate binomial regression models with the log link function were used to determine the relative risk of SGA associated with increasing quartiles of each biomarker. Restricted cubic splines were used to test for nonlinearity of these associations.

RESULTS

A total of 60 participants (13.9%) gave birth to SGA infants. Compared to those in the first quartile, the risk of SGA was reduced among those in the fourth quartiles of vascular endothelial growth factor-A (adjusted risk ratio [RR], 0.38; 95% confidence interval [CI], 0.19-0.74), placental growth factor (adjusted RR, 0.28; 95% CI, 0.12-0.61), soluble fms-like tyrosine kinase-1 (adjusted RR, 0.48; 95% CI, 0.23-1.01), monocyte chemoattractant protein-1 (adjusted RR, 0.48; 95% CI, 0.25-0.92), and leptin (adjusted RR, 0.46; 95% CI, 0.22-0.96).

CONCLUSION

Our findings provide evidence of altered angiogenic and inflammatory mediators, at midpregnancy, in women who went on to deliver SGA infants.

Perinatal systemic inflammatory responses of growth-restricted preterm newborns

AIM

To compare the early post-natal pattern of systemic inflammation in growth-restricted infants born before the 28th week of gestation to that of appropriately grown peers.

METHODS

We measured the concentrations of 25 inflammation-related proteins in blood spots collected from 939 newborns during the first 2 post-natal weeks. We calculated the odds ratios (99% confidence intervals) that concentrations would be in the highest quartile.

RESULTS

Severely growth-restricted infants (birth weight Z-score <-2) were not at increased risk of systemic inflammation shortly after birth. On post-natal day 14, however, they were significantly more likely than their peers to have a CRP, IL-1β, IL-6, TNF-α, IL-8, MCP-4, ICAM-1, ICAM-3, E-SEL, MMP-9, VEGF-R2 and/or IGFBP-1 concentration in the highest quartile. These increased risks could not be attributed to delivery indication, bacteremia or duration of ventilation.

CONCLUSION

Growth-restricted preterm newborns appear to be at increased risk of elevated concentrations of inflammation-associated proteins by post-natal day 14.

Maternal magnesium supplementation reduces intrauterine growth restriction and suppresses inflammation in a rat model

OBJECTIVE

Intrauterine growth restriction (IUGR) is associated with increased inflammatory responses. We sought to investigate whether magnesium (Mg) attenuates inflammation and IUGR in a rat model.

STUDY DESIGN

Pregnant Wistar rats (12 weeks, gestational day 18) were randomly assigned to 1 of 4 groups: normal diet with bilateral uterine artery ligation (BL) (n = 6) or sham surgery (SH) (n = 5); and Mg chloride (MgCl2) 1% (wt/vol) in the drinking water throughout gestation + BL (MgBL) (n = 6) or SH (MgSH) (n = 5). Dams were euthanized 24 hours postsurgery (gestational day 19). Maternal plasma, fetal plasma (pooled), individual amniotic fluid (AF) samples, and placentas (PL) were collected and assessed from live fetal pups only (BL, n = 36; SH, n = 20; MgBL, n = 20; MgSH, n = 20). All samples were analyzed for cytokines/chemokines (interleukin [IL]-6, IL-1β, chemokine [C-X-C motif] ligand 1 [CXCL1], chemokine [C-C motif] ligand 2 [CCL2], and tumor necrosis factor [TNF-α] sensitivity <3 pg/mL) using a multiplex platform. Data were analyzed using Mann Whitney, analysis of variance, and Fisher exact tests.

RESULTS

The incidence of IUGR (pup weight <10th percentile of SH) in the MgBL group was significantly lower (31%) than the BL group (86.3%) (relative risk, 0.36; 95% confidence interval, 0.2-0.6; P < .0001). BL significantly increased AF levels of IL-6, IL-1β, TNF-α (P < .05), and CCL2 (P < .001) vs SH and PL levels of IL-6, IL-1β, CCL2 and CXCL1 (P < .001), and TNF-α (P < .05) vs SH. Maternal MgCl2 supplementation significantly decreased IL-1β, TNF-α, and CCL2 levels in AF and IL-1β in PL tissues of MgBL vs BL rats (P < .0001).

CONCLUSION

Maternal oral MgCl2 supplementation reduced BL-induced IUGR by 64% and suppressed cytokine/chemokine levels in the AF and PL.

Human cytomegalovirus-induces cytokine changes in the placenta with implications for adverse pregnancy outcomes

Human cytomegalovirus (CMV) infection of the developing fetus can result in adverse pregnancy outcomes including death in utero. Fetal injury results from direct viral cytopathic damage to the CMV-infected fetus, although evidence suggests CMV placental infection may indirectly cause injury to the fetus, possibly via immune dysregulation with placental dysfunction. This study investigated the effects of CMV infection on expression of the chemokine MCP-1 (CCL2) and cytokine TNF-α in placentae from naturally infected stillborn babies, and compared these changes with those found in placental villous explant histocultures acutely infected with CMV ex vivo. Tissue cytokine protein levels were assessed using quantitative immunohistochemistry. CMV-infected placentae from stillborn babies had significantly elevated MCP-1 and TNF-α levels compared with uninfected placentae (p = 0.001 and p = 0.007), which was not observed in placentae infected with other microorganisms (p = 0.62 and p = 0.71) (n = 7 per group). Modelling acute clinical infection using ex vivo placental explant histocultures showed infection with CMV laboratory strain AD169 (0.2 pfu/ml) caused significantly elevated expression of MCP-1 and TNF-α compared with uninfected explants (p = 0.0003 and p<0.0001) (n = 25 per group). Explant infection with wild-type Merlin at a tenfold lower multiplicity of infection (0.02 pfu/ml), caused a significant positive correlation between increased explant infection and upregulation of MCP-1 and TNF-α expression (p = 0.0001 and p = 0.017). Cytokine dysregulation has been associated with adverse outcomes of pregnancy, and can negatively affect placental development and function. These novel findings demonstrate CMV infection modulates the placental immune environment in vivo and in a multicellular ex vivo model, suggesting CMV-induced cytokine modulation as a potential initiator and/or exacerbator of placental and fetal injury.

Serum chemokine levels and developmental outcome in preterm infants

BACKGROUND

Cytokines and chemokines during perinatal period may involve the neurological development of newborns.

AIMS

We investigated the association of circulating chemokines during neonatal period with the outcome of premature infants.

STUDY DESIGN

The prospective study enrolled 29 very low birth weight (<1500 g) and appropriate-for-date infants having no underlying diseases. Serum concentrations of chemokines (CXCL8, CXCL9, CXCL10 and CCL2) and cytokines at birth and 4 weeks postnatal age were measured. Developmental quotients (DQ) at 3 years of age by the Kyoto Scale of Psychological Development were studied for the association with chemokine/cytokine levels and clinical variables including chorioamnionitis, Apgar scores, ventilator treatment and supplemental oxygen.

RESULTS

CXCL8 levels at birth and days of ventilator treatment were negatively, CCL2 levels at 4 weeks after birth and 5-minute Apgar scores were positively correlated with the DQ of postural-motor [P-M] area at 3 years of age, respectively (CXCL8: correlation coefficient [CC]=-0.394, p=0.037, ventilation: CC=-0.518, p=0.006, CCL2: CC=0.528, p=0.013, and Apgar score: CC=0.521, p=0.005). Infants showing both ≥50 pg/ml of CXCL8 at birth and <250 pg/ml of CCL2 4 weeks after birth had lower DQ of P-M than those who did not (p<0.001). Multivariate analyses indicated that CCL2 levels at 4 weeks of age were higher in infants who attained normal DQ of P-M (≥85) (adjusted mean, 338.4 [95% confidence interval, 225.5-507.8]) than in those who did not (<85) (159.0, [108.2-233.7]) (p=0.019).

CONCLUSION

Circulating patterns of CXCL8 (IL-8) and CCL2 (MCP-1) during the neonatal period might affect the neurological development of preterm infants.

Cytokine profiles of seventeen cytokines, growth factors and chemokines in cord blood and its relation to perinatal clinical findings

Few papers have investigated the cytokine profiles of multiple cytokines in cord blood. We obtained cord blood samples from 224 infants admitted to our neonatal intensive care unit. Cytokine profiles of 17 cytokines were investigated using cytometric bead array technology. We found a wide variety of cytokines of various levels which ranged from 0.59pg/ml (in Interleukin (IL)-4) to 222.0pg/ml (in macrophage inflammatory protein-1beta. Pro-inflammatory cytokines were highly correlated with each other and with granulocyte-colony stimulating factor and IL-8. On the contrary, IL-5, IL-13, and IL-17 did not show any significant correlation with other cytokines. Several maternal factors were strongly related to several cytokines in cord blood. IL-6, IL-8 and monocyte chemotactic protein-1 were closely related to certain neonatal diseases in preterm neonates. Some cytokines may be regulated independently of each other, while others appear to work as a network affecting physiological and pathological conditions in the fetus.