Differential secretion of chemokines from peripheral blood in pregnant compared with non-pregnant women

Genital Dysbiosis and Different Systemic Immune Responses Based on the Trimester of Pregnancy in SARS-CoV-2 Infection

Respiratory infections are common in pregnancy with conflicting evidence supporting their association with neonatal congenital anomalies, especially during the first trimester. We profiled cytokine and chemokine systemic responses in 242 pregnant women and their newborns after SARS-CoV-2 infection, acquired in different trimesters. Also, we tested transplacental IgG passage and maternal vaginal-rectal microbiomes. IgG transplacental passage was evident, especially with infection acquired in the first trimester. G-CSF concentration-involved in immune cell recruitment-decreased in infected women compared to uninfected ones: a beneficial event for the reduction of inflammation but detrimental to ability to fight infections at birth. The later the infection was acquired, the higher the systemic concentration of IL-8, IP-10, and MCP-1, associated with COVID-19 disease severity. All infected women showed dysbiosis of vaginal and rectal microbiomes, compared to uninfected ones. Two newborns tested positive for SARS-CoV-2 within the first 48 h of life. Notably, their mothers had acute infection at delivery. Although respiratory infections in pregnancy are reported to affect babies' health, with SARS-CoV-2 acquired early during gestation this risk seems low because of the maternal immune response. The observed vaginal and rectal dysbiosis could be relevant for neonatal microbiome establishment, although in our series immediate neonatal outcomes were reassuring.

Macrophages modulate the growth and differentiation of rhesus monkey embryonic trophoblasts

PROBLEM

Immune cells within the endometrium at implantation are thought to play an important role in implantation, although their exact role is not well understood.

METHOD OF STUDY

A co-culture system of rhesus monkey embryos and maternal immune cells was established. Blastocysts obtained by in vitro fertilization were co-cultured with peripheral blood cells or decidual macrophages. Culture media were collected to assess secretions. Embryo growth was monitored, and trophoblasts were evaluated for proliferation, apoptosis, and differentiation.

RESULTS

Embryonic trophoblast outgrowths were visible within 6 days of culture, and the area of embryo outgrowth was reduced when blastocysts were cultured with peripheral-derived or decidual macrophages. Trophoblast proliferation was not significantly affected with macrophage co-culture while chorionic gonadotropin secretion was increased. Trophoblast expression of CDH 11 and GJA1 was increased, suggesting that macrophages accelerate differentiation of peri-implantation trophoblasts.

CONCLUSIONS

These results indicate an important role of macrophages in placentation and pregnancy success.

Effects of Acupuncture on CCL2 and CXCL8 Expression and the Subset of uNK Cells in Rats with Embryo Implantation Failure

The present study was designed to investigate the efficacy and mechanism of acupuncture treatment on embryo implantation failure in rats. The pregnant rats were randomized into normal group (N), implantation failure group (M), acupuncture treatment group (A), and progestin treatment group (W). The embryo implantation failure model was established by mifepristone. Efficacy of acupuncture treatment was evaluated by the number of implanted embryos. The expression of CCL2 and CXCL8 and the subset of uterine natural killer cells in the endometrium were detected. We demonstrated that the number of implanted embryos was dramatically reduced after mifepristone (M group) treatment, while the acupuncture (A group) and progestin (W group) treatments significantly rescued impaired embryo implantation. The protein and mRNA expressions of CCL2 and CXCL8 were significantly reduced by mifepristone treatment, but the attenuated expression of CCL2 and CXCL8 was markedly reversed by acupuncture or progestin treatment. More importantly, acupuncture and progestin could markedly increase the subset of uNK cells in rats with embryo implantation failure. These evidences suggest that acupuncture is able to modulate the endometrial immune microenvironment and thus improve embryo implantation in pregnant rats, which provides solid experimental evidence for the curative effect of acupuncture treatment on infertility.

Gene expression in chorionic villous samples at 11 weeks of gestation in women who develop pre-eclampsia later in pregnancy: implications for screening

OBJECTIVES

To determine the gene expression profile in chorionic villous samples (CVSs) of women destined to develop pre-eclampsia (PE).

METHOD

Case-control study encompassing five women destined to develop PE [cases matched for gestational age with 30 controls]. We quantified mRNA expression on tissue samples from CVS of normal and PE patients. We then assessed mRNA expressions of cathepsin (CTSD), angiopoietin 2 (ANGPT2), interleukin 8, chemokine (C-X-C motif) ligand 10, neurokinin B (NKB), matrix metallopeptidase 9, major histocompatibility complex, class I, C (HLA-C)and human leukocyte antigen-G (HLA-G). Data were analyzed by nonparametric rank analysis.

RESULTS

For all the mRNA species considered in this study, except CTSD and ANGPT2, all the mean observed ranks in the PE group were significantly altered compared with the rank expectation among controls. mRNA for NKB and HLA-C were the markers with the highest degree of aberration in PE, compared with those in controls.

CONCLUSION

Our study has directly showed that gene expressions relating to trophoblastic cell invasion or utero-placental hemodynamic adaptation are altered in the first trimester trophoblasts that go on to develop PE later. These results posit the use of residual CVS as a possible screening method for PE.

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

Monocyte-chemotactic-protein-1 (MCP-1) plays vital roles in immune response, angiogenesis, and pregnancy outcome. We investigated plasma MCP-1 concentrations in 40 mothers and their 20 intrauterine-growth-restricted (IUGR) and 20 appropriate-for-gestational-age (AGA) fetuses and neonates on postnatal days 1 (N1) and 4 (N4). Maternal and fetal MCP-1 concentrations were decreased (P<001 and P = .018, resp.), whereas N1 MCP-1 concentrations were elevated in IUGR group (P = .012). In both groups, fetal MCP-1 concentrations were lower compared to N1 and N4 ones (P = .045, P = .012, resp., for AGA, P< .001 in each case for IUGR). Reduced maternal and fetal MCP-1 concentrations in IUGR may reflect failure of trophoblast invasion, suggesting that down-regulation of MCP-1 may be involved in the pathogenesis of IUGR. Increased MCP-1 concentrations in IUGR neonates and higher postnatal ones in all infants may be attributed to gradual initiation of ex utero angiogenesis, which is possibly enhanced in IUGR.

Leptin, IL-10 and Inflammatory Markers (TNF-?, IL-6 and IL-8) in Pre-Eclamptic, Normotensive Pregnant and Healthy Non-Pregnant Women

PROBLEM

Despite progress in immunobiology, pre-eclampsia (PE) remains one of the most common reasons for women to die during pregnancy. The widespread pathophysiological mechanisms are endothelial dysfunction, oxidative stress and inflammation. The aim of this study was to assess the alteration in the levels of leptin, interleukin (IL)-10 and inflammatory cytokines [tumour necrosis factor (TNF)-alpha, IL-6 & IL-8] in pre-eclamptic (severe and mild), healthy pregnant and non-pregnant women and correlate these parameters with disease severity.

METHOD OF STUDY

The levels of leptin, IL-10 and inflammatory cytokines were measured by high sensitivity enzyme-linked immunoabsorbant assay. The study subjects were 54 pre-eclamptic women (ten severe and 45 milder), compared by age matched 50 healthy pregnant and 27 non-pregnant women. Kruskal-Wallis non-parametric analyses of variance followed by Mann-Whitney U-test were used for statistical analysis.

RESULTS

The levels of leptin, TNF-alpha, IL-6 & IL-8 in pre-eclamptic subjects were increased significantly when compared with the healthy control pregnant and non-pregnant (P < 0.000). The concentration of IL-10 has shown different pattern as its level decreased significantly (0.001) in pre-eclamptic women (overall) in comparison with control subjects (pregnant & non-pregnant). A combination of 80% or higher sensitivity and specificity was seen in the parameters analysed, except IL-8 and IL-10.

CONCLUSION

Our findings suggest a relationship among TNF-alpha, IL-6, IL-8, IL-10 and leptin and indicate that altered levels of above markers in PE might be used as markers of pro-inflammation/anti-inflammation and endothelial dysfunction in pre-eclamptic pregnancies. These results also advocate the abnormal leptin and cytokine responses in mother, which might be involved in the pathogenesis of PE.

Elevated Plasma Levels of Interleukin 1β, Tumour Necrosis Factor α and Monocyte Chemotactic Protein 1 Are Associated with Pregnancy Toxaemia in Ewes

Pregnancy toxaemia is a metabolic disorder that results from an inadequate energy supply to the growing maternal-fetal unit. The mechanism underlying the pathogenesis of the syndrome has not been fully clarified; however, a key role for cytokines and chemokines including interleukin 1 beta (IL-1 beta), tumour necrosis factor alpha (TNF-alpha) and monocyte chemotactic protein 1 (MCP-1) has been indicated in women and experimental animals. However, information on the maternal plasma levels of IL-1 beta, TNF-alpha and MCP-1 in ewes with pregnancy toxaemia is limited. Thus, the present study was designed to determine plasma IL-1 beta, TNF-alpha and MCP-1 concentrations in ewes with severe (n=6) and mild (n=4) naturally occurring pregnancy toxaemia and in uncomplicated pregnant ewes (n=10) using enzyme-linked immunosorbent assay (ELISA). All ewes with pregnancy toxaemia had significantly lower body temperature and respiratory rate than uncomplicated pregnant ewes (p<0.05). With the highest concentrations in severe cases, heart rate, proteinuria and serum uric acid levels as well as plasma IL-1 beta, TNF-alpha and MCP-1 were significantly different among all three groups (p<0.05). The plasma concentrations of IL-1 beta in control ewes and ewes with mild and severe toxaemia were 15.81 +/- 3.90 pg/ml, 23.83 +/- 2.42 pg/ml and 34.55 +/- 8.03 pg/ml, respectively. The plasma concentrations of TNF-alpha in control ewes and ewes with mild and severe toxaemia were 7.71 +/- 1.61 pg/ml, 16.13 +/- 3.63 pg/ml, and 22.85 +/- 3.64 pg/ml, respectively. The plasma concentrations of MCP-1 in control ewes and ewes with mild and severe toxaemia were 101.70 +/- 9.86 pg/ml, 134.75 +/- 6.24 pg/ml, and 157.67 +/- 9.69 pg/ml, respectively. Moreover, plasma IL-1 beta, TNF-alpha and MCP-1 levels were positively correlated with clinical and well-establish biochemical parameters of pregnancy toxaemia, serum uric acid and proteinuria (p<0.01). Concomitant increase of plasma IL-1 beta, TNF-alpha and MCP-1 concentrations along with serum uric acid, proteinuria, and worsening of the clinical signs indicates that such cytokines are involved in the aetiopathogenesis and in perpetuation of the local and systemic inflammatory reactions in pregnancy toxaemia in ewes. Hence, plasma IL-1 beta, TNF-alpha and MCP-1 may potentially serve as markers to monitor prognosis of pregnancy toxaemia in ewes.

Immune cells contribute to systemic cross-talk between the embryo and mother during early pregnancy in cooperation with the endocrine system

In early pregnancy, human chorionic gonadotropin (HCG) stimulates the corpus luteum to produce progesterone that in turn maintains human embryo implantation in the uterus. This inevitable communication through blood circulation can be called 'systemic cross-talk between the embryo and mother'. Despite considerable evidence suggesting that the human corpus luteum cannot be maintained by HCG alone, no other responsible soluble factors have been proposed. We found that peripheral blood mononuclear cells (PBMC) derived from pregnant women promoted progesterone production by human luteal cells and propose that both hormones and immune cells participate in this systemic cross-talk. This systemic cross-talk by immune cells is believed to operate in embryo implantation. Splenocytes derived from pregnant mice promoted endometrial differentiation and embryo implantation in vivo. Human PBMC derived from women early in pregnancy promoted invasion of murine embryos in vitro. In addition, recombinant HCG increased the effects of human PBMC on murine embryo invasion. Human chorionic gonadotropin also increased chemokine production by human PBMC through a lectin-glycan interaction, which is a primitive pathway in the immune system. Furthermore, chemokines were shown to induce human trophoblast invasion. These findings suggest that the immune system positively contributes to systemic cross-talk between the embryo and mother in cooperation with the endocrine system. (Reprod Med Biol 2006; 5: 19-29).

Th1/Th2 cytokines balance--yin and yang of reproductive immunology

For years conception of Th2 overbalance during pregnancy has been a paradigm for immunology of reproduction, while Th1 activity has been presented as unwanted component. Studies concerning Th1/Th2 balance in physiological and complicated pregnancy have been reviewed. Th1 activity during early peri-implantation period, premature and term labour not only accompanies but even predominates over Th2 activity. Th1 activity plays important role in promotion of Th2 response, regulation of placentation process, defense against infections and initiation of delivery. Together with Th2 activity it is necessary component of immunological reactions during pregnancy, both activities being inseparable like yin and yang. So paradigm of "Th1-Th2 cooperation" is much closer to reality than "Th2 phenomenon".

Maternal serum interleukin-1 beta, -6 and -8 levels and potential determinants in pregnancy and peripartum

AIMS

To measure maternal serum interleukins (IL) in pregnancy, delivery and early puerperium, and to identify their potential determinants.

METHODS

Prospective longitudinal measures of serum IL-1 beta, IL-6 and IL-8 in 38 healthy pregnant women at antenatal visits, through labor and delivery, with clinical correlates (infection, vaginal hemorrhage and anemia) recorded by questionnaire.

RESULTS

Pregnancy IL levels remained consistently low. IL-1 beta increased shortly before delivery, then returned to pregnant levels, except where blood loss exceeded 500 ml. IL-6 and IL-8 rose at labor onset and exceeded pregnancy levels through postpartum day three. Postpartum IL-6 was higher after non-elective cesarean section than after spontaneous delivery (P < 0.0001), and where blood loss exceeded 500 ml. IL-6 and IL-8 were higher with systemic infection during delivery (P < 0.0001) and on postpartum day one (P < 0.05); IL-8 was higher in anemia (delivery: P < 0.005; postpartum day 1: P < 0.05). Differences due to delivery mode and systemic infection remained significant after correction for other conditions.

CONCLUSIONS

Labor-dependent inflammation increases all IL levels at delivery. Further studies with larger sample sizes are required to establish reference values differentiating physiology from pathology as an aid to peripartum management.

Expression of IL-4, IL-8 and IL-18 messenger RNAs in maternal peripheral blood and relationships with the HbF-gamma chain mRNA in it

PROBLEM

This study was designed to examine immunological changes in maternal peripheral blood and the relationship of these changes with the amount of fetal cells in the blood.

METHOD OF STUDY

The expression of interleukin-4 (IL-4), IL-8, IL-18 and fetal hemoglobin gamma chain (HbF-gamma chain) messenger RNAs (mRNAs) in maternal peripheral blood was measured by a quantitative reverse transcription-polymerase chain reaction method.

RESULTS

In maternal peripheral blood, the expression of IL-4 mRNA was up-regulated from the second gestational month (GM) to delivery. The expression of IL-8 and IL-18 mRNAs was down-regulated from the third or fourth GM until the eighth or ninth GM, respectively, and both increased before the onset of labor, though IL-4 mRNA decreased. The expression of IL-8 and IL-18, but not IL-4, mRNAs was correlated with that of HbF-gamma chain mRNA.

CONCLUSIONS

Immunological interactions between maternal peripheral immune cells and fetal cells appear to be related to the onset of labor.

Trophoblasts acquire a chemokine receptor, CCR1, as they differentiate towards invasive phenotype

At the human feto-maternal interface, trophoblasts differentiate towards extravillous trophoblasts (EVTs) and form the cell column. EVTs acquire invasive activity in the distal part of the cell column and begin to migrate into the maternal tissue. We previously reported that dipeptidyl peptidase IV (DPPIV) is expressed on EVTs in the proximal part of cell column and is involved in the inhibition of their migration. Because DPPIV has been shown to degrade several chemokines, we examined possible roles of chemokines in EVT migration. Immunohistochemistry demonstrated that C-C chemokine receptor 1 (CCR1) was hardly detected on cytotrophoblasts and syncytiotrophoblast but was expressed on EVTs in the cell column. In vitro, CCR1 protein was also present on the surface of EVTs that grew out from chorionic villous explants cultured under 20% O2. Chemokines that can bind to CCR1 (CCR1 ligands), such as regulated on activation, normal T cell expressed and secreted (RANTES) and macrophage inflammatory protein-1alpha (MIP-1alpha), were confirmed in the decidual tissues by RT-PCR and immunohistochemistry. These CCR1 ligands promoted the migration of the EVTs that were isolated from the explant cultures in vitro. These results indicate that CCR1 is expressed on trophoblasts as they differentiate to EVTs and that CCR1 ligands produced from the decidual tissue induce EVT migration. By contrast, CCR1 was scarcely expressed on EVTs that grew out from villous explants cultured in 1% O2, indicating that a relatively high oxygenic environment is needed to induce CCR1 expression. Moreover, CCR1 expression on the isolated EVTs was significantly reduced in the presence of decidua-conditioned medium. Such regulation of CCR1 by surrounding oxygenic and decidual environments supports a close correlation between EVT invasion and their expression of CCR1. This study demonstrates that trophoblasts acquire CCR1 as they differentiate to an invasive phenotype at the villus-anchoring sites and indicates a novel role for the chemokine-CCR1 system in the initial step of trophoblastic invasion towards the maternal tissue.

Sex differences in infection and sepsis

Sex and gender-based differences in responses to infection and sepsis are evident. Estrogens increase immune function, sometimes to the point of inducing autoimmune disease. Testosterone suppresses immune function, sometimes leading to a worsened outcome following traumatic injury. Therapies using sex hormones to improve outcomes after sepsis and hemorrhagic shock and to reduce exacerbations of autoimmune diseases are being studied. Differences in sex hormone levels may not tell the whole story. Studies of immune function in girls and boys before puberty may be helpful. Differences found early might indicate that factors other than estrogen and androgen levels are contributing. Variations in societal role acculturation and exposures that are gender based also may be involved. Clinicians must consider sex and gender when attempting to determine the risk of infection, sepsis, and immune dysfunction in populations. Clinical applications of sex and gender differences are just beginning to occur with the genesis of sex hormone-based treatments. The large-scale efficacy of such treatments has yet to be reported. Innovative strategies based on sex or gender differences in immune responses may soon be available and may lead to essential data for clinical decision making. The impact of sex and gender differences on long-term health outcomes remains to be seen.

The action of prostaglandin E2 on the human cervix: stimulation of interleukin 8 and inhibition of secretory leukocyte protease inhibitor

OBJECTIVE

The objective of this study was to investigate regulation of inflammatory mediators implicated in cervical ripening and to explore the mechanisms by which the clinically effective agent prostaglandin E2 may mediate cervical ripening.

STUDY DESIGN

Cervical biopsy specimens were taken from healthy, nonpregnant women undergoing a hysterectomy for a benign nonmalignant condition and were cultured, with treatments in quadruplicate, for 24 hours in media supplemented with progesterone, dexamethasone, nitric oxide, interleukin 8, and prostaglandin E2. Media were collected and assayed by enzyme-linked immunosorbent assay for interleukin 8, secretory leukocyte protease inhibitor, and prostaglandin E2. Ethical approval was obtained for this study from the local ethics committee.

RESULTS

Interleukin 8 release from cervical explants was stimulated by prostaglandin E2 and nitric oxide and inhibited by progesterone and dexamethasone. Secretory leukocyte protease inhibitor release from cervical explants was stimulated by progesterone and inhibited by prostaglandin E2. Prostaglandin E2 release from cervical explants was stimulated by nitric oxide.

CONCLUSION

Complex interactions occur between inflammatory cytokines within the cervix; these results further our understanding of the mechanism of cervical ripening.

An innate view of human pregnancy

Our understanding of the immunology of pregnancy has been dominated by the fetal allograft model and by changes in the maternal-specific immune system. Here, Gavin Sacks and colleagues draw attention to substantial and contrasting changes in the maternal innate system and hypothesize that its function and that of monocytes in particular, has a central role in the maternal-fetal relationship.