Role of maternal interleukin-8 (IL-8) in normal-term birth in the human

Regulatory B-Cells Are Associated Negatively With Regulatory T-Cells and Positively With Cytokines in Peripheral Blood of Pregnant Women

PROBLEM

Regulatory B-cells (Bregs, CD19+CD24hiCD38hi) are a specialized B-cell subset that suppresses immune responses and potentially contribute to the maintenance of an immune-privileged environment for fetal development during pregnancy. However, little is known about the surrounding immunological environment of Bregs in gestational physiology. The relationship of regulatory T-cells (Tregs, CD4+CD25hiCD127loFoxP3+) to Bregs in coordinating immunoregulation during pregnancy is unknown. We aimed to determine whether peripheral concentrations of Bregs and/or PD-L1-expressing Bregs correlated with Tregs and cytokines during pregnancy.

METHOD

Peripheral blood samples were obtained from 29 pregnant women at mean 12 weeks' gestation. Participants were age ≥ 18, self-identified as Latina/Hispanic, and N = 12 primigravid. Peripheral blood mononuclear cells were isolated, stained, and analyzed by flow cytometry to determine percentages of Tregs from CD4+ T-cells and five Treg subsets defined by immune checkpoint markers, and Bregs and PD-L1+ Bregs from total B-cells. Levels of 13 cytokines were measured on a Meso Scale Discovery multiplex platform.

RESULTS

Bregs positively correlated with pro-inflammatory cytokine interleukin (IL)-6. PD-L1+ Bregs positively correlated with T-cell suppressive cytokine IL-10. PD-L1+ Bregs negatively correlated with Tregs and Helios+, CTLA-4+, PD-1+, TIGIT+, and TIM3+ Tregs. For primigravida, PD-L1+ Bregs correlated positively with IL-10 and negatively with Helios+ and TIGIT+ Tregs. For multigravida, PD-L1+ Bregs correlated positively with IL-8 and negatively with Helios+, CTLA-4+, PD-1+, and TIGIT+ Tregs.

CONCLUSIONS

This study provides insight into the immunosuppressive role of Bregs and PD-L1+ Bregs during human pregnancy. Our results suggest that PD-L1+ Bregs can employ suppressive mechanisms to limit pro-inflammatory responses in primigravida.

The Role of the NLRP3 Inflammasome in the Molecular and Biochemical Mechanisms of Cervical Ripening: A Comprehensive Review

The uterine cervix is one of the key factors involved in ensuring a proper track of gestation and labor. At the end of the gestational period, the cervix undergoes extensive changes, which can be summarized as a transformation from a non-favorable cervix to one that is soft and prone to dilation. During a process called cervical ripening, fundamental remodeling of the cervical extracellular matrix (ECM) occurs. The cervical ripening process is a derivative of many interlocking and mutually driving biochemical and molecular pathways under the strict control of mediators such as inflammatory cytokines, nitric oxide, prostaglandins, and reactive oxygen species. A thorough understanding of all these pathways and learning about possible triggering factors will allow us to develop new, better treatment algorithms and therapeutic goals that could protect women from both dysfunctional childbirth and premature birth. This review aims to present the possible role of the NLRP3 inflammasome in the cervical ripening process, emphasizing possible mechanisms of action and regulatory factors.

Immunohistochemical study of MMP-2, MMP-9, EGFR and IL-8 in decidual and trophoblastic specimens of recurrent pregnancy loss cases

BACKGROUND AND AIM

Unexplained recurrent pregnancy loss has been a a challenging research task to experts since there is no explicit pathophysiological mechanism and therefore, the treatment remains elusive. Immunological imbalance and morphological abnormalities are under investigation. This study aims to evaluate the implication of MMP-2, MMP-9, EGFR, and IL-8 in recurrent pregnancy loss cases.

MATERIALS & METHODS

The study was carried out through comparison among two groups; the unexplained miscarriage group which consisted of 22 women, and the control group consisted of 18 women, who had electively terminated their pregnancies. Both groups were in the first trimester of gestation. The specimens included the trophoblast, decidua basalis, and decidua parietalis. The study was conducted via immunohistochemical methods. Antibodies were used against MMP-2, MMP-9, EGFR, and IL-8. The results were presented at a contingency table and were statistically analyzed with the Chi-Square Test (X²).

RESULTS

There were remarkable disparities in some cases in the comparison of the two groups. MMP-9 was detected significantly high in recurrent pregnancy loss (RPL) cases, both on trophoblastic and decidual specimens (p-value < .00001), MMP-2 displayed no difference among the two groups (mild to moderate detection on trophoblast and almost negative on decidual tissues). EGFR was highly detected in trophoblastic tissue (p-value = .014). IL-8 detection was particularly different in both trophoblast and decidua parietalis of the two groups (p-value < .01).

CONCLUSION

The study revealed both morphological and immunological dysregulations that might participate in the RPL pathogenesis.

The relationship of fetal sex and maternal race and ethnicity with early and late pregnancy C-reactive protein and interleukin-8

PROBLEM

Promotion of a healthy pregnancy is dependent on a coordinated immune response that minimizes inflammation at the maternal-fetal interface. Few studies investigated the effect of fetal sex on proinflammatory biomarkers during pregnancy and whether maternal race could impact this association. We aimed to examine whether fetal sex could, independently of maternal race/ethnicity and the condition of pregnancy (normal vs. complicated), impact inflammatory markers (C-reactive protein [CRP] and interleukin-8 [IL-8] levels) in early and late pregnancy.

METHODS OF STUDY

This study was a cohort analysis using prospectively collected data from pregnant women who participated in the Vitamin Antenatal Asthma Reduction Trial (VDAART, N = 816). Maternal serum CRP and IL-8 levels were measured in early and late pregnancy (10-18 and 32-38 weeks of gestation, respectively). Five hundred and twenty-eight out of 816 pregnant women who participated in the trial had available CRP and IL-8 measurements at both study time points. We examined the association of fetal sex with early and late CRP and IL-8 levels and their paired sample difference. We further investigated whether maternal race/ethnicity, pregnancy complications (i.e., preeclampsia and gestational diabetes), and early pregnancy body mass index (BMI) could affect the association between these two biomarkers and fetal sex adjusting for potential confounders. For this purpose, we used generalized linear and logistic regression models on log-normalized early and late CRP and IL-8 levels as well as their split at median to form high and low groups.

RESULTS

Women pregnant with male fetuses (266/528 = 56.5%) had higher CRP levels in early to mid-pregnancy (β = .18: 95% confidence interval [CI]: CI = 0.03-0.32; p = .02). Twenty-seven percent (143/528) of the study subjects were Hispanic. Hispanic African American [AA] women and women of races other than White and AA had higher levels of CRP at early to mid-pregnancy compared with White women (β = .57; 95% CI: 0.17-0.97; p < .01 and β = .27; 95% CI: 0.05-0.48; p = .02, respectively). IL-8 levels were not associated with fetal sex in early and late pregnancy (p's > .05). Other factors such as gestational diabetes and early pregnancy BMI were associated with higher CRP levels and higher CRP and IL-8 levels, respectively. Dichotomizing log-normalized cytokine levels at the median in a sensitivity analysis, women with male fetuses had lower odds of high (above-median) IL-8 levels at early pregnancy. Also, women with races other than AA and White carrying male fetuses had higher odds of having high (above-median) late-pregnancy CRP and early-pregnancy IL-8 levels (adjusted odds ratio [aOR] = 3.80, 95% CI: 0.24-1.23; p = .02 and aOR = 3.57; 95% CI: 0.23-1.03; p = .02, respectively). Of the pregnancy complications, women with gestational diabetes mellitus had a higher paired difference of early and late pregnancy CRP levels (β = .38; 95% CI: 0.09-0.68; p = .01), but no difference in IL-8 levels (p's > .05). No associations between the inflammatory markers and preeclampsia were found.

CONCLUSION

Fetal sex is associated with CRP in early pregnancy and an association with IL-8 in early pregnancy is implied. Our study further indicates that maternal race/ethnicity could be a contributing factor in the relationship between fetal sex and inflammatory responses during pregnancy. However, the specificity and level of the contribution might vary by type of cytokine, pregnancy stage, and other confounding factors such as BMI that may impact these associations.

Racial differences in the associations between adiposity, placental growth hormone and inflammatory cytokines in pregnant women

Background

The prevalence of obesity among women of child-bearing age has contributed to an increased risk of pregnancy complications with a disproportional impact on women of lower socioeconomic status and among certain racial groups. In particular, socio-demographic and historical factors have resulted in higher rates of premature births and small-for-gestational age infants among Black women, which may be associated with placental function during pregnancy. The current study investigated the influence of maternal pre-pregnancy adiposity and race on the associations between inflammatory proteins, placental growth hormone (PGH), and infant birthweight. This information was collected for a subsample of 109 participants (Black, n = 39 vs. White, n = 70) from the Brain and Early Experiences (BEE) study.

Methods

Serum samples were acquired late in the second trimester to assess PGH levels, C-reactive protein (CRP), interleukin 6 (IL-6), interleukin 8 (IL-8), and interleukin-1 receptor antagonist (IL-1Ra). Participant questionnaire responses provided information on pre-pregnancy BMI, health, race, educational attainment, and infant birthweight. Bivariate correlations and multiple linear regression models were utilized to evaluate associations by race between preconception adiposity, inflammatory markers and PGH.

Results

After controlling for covariates including maternal age and education, gestational age, and fetal sex, regression models indicated that pre-pregnancy BMI was negatively associated with PGH (β=-0.42, p<0.05) and IL-8 was positively associated with PGH (β=0.35, p<0.05) among the Black mothers only; neither were significantly associated with PGH in the White mothers. When extending models to birth outcomes, BMI was positively associated with birthweight corrected for gestational age (BWz) (β=0.24, p<0.05) and educational attainment was negatively associated with BWz (β=0.28, p<0.05) for infants of White women. In contrast, neither variable was predictive of BWz for infants of Black mothers.

Conclusion

Future work is needed to investigate racial differences in the association between adiposity and placental functioning, which are likely to contribute to differential effects on pregnancy outcomes and fetal growth.

Cytokine see-saw across pregnancy, its related complexities and consequences

During pregnancy, a woman's immune system adapts to the changing hormonal concentrations, causing immunologic transition. These immunologic changes are required for a full-term pregnancy, preserving the fetus' innate and adaptive immunity. Preterm labor, miscarriage, gestational diabetes mellitus, and pre-eclampsia are all caused by abnormal cytokine expression during pregnancy and childbirth. A disruption in the cytokine balance can lead to autoimmune diseases or microbiologic infections, or to autoimmune illness remission during pregnancy with postpartum recurrence. The cytokine treatments are essential and damaging to the developing fetus. The current review summarizes the known research on cytokine changes during pregnancy and their possible consequences for pregnant women. Studies suggest that customizing medication for each woman and her progesterone levels should be based on the cytokine profile of each pregnant woman. Immune cells and chemicals play an important function in development of the placenta and embryo. During pregnancy, T cells divide and move, and a careful balance between proinflammatory and anti-inflammatory cytokines is necessary. The present review focuses on the mother's endurance in generating fetal cells and the immunologic mechanism involved.

Relationship between the Dietary Inflammatory Index Score and Cytokine Levels in Chinese Pregnant Women during the Second and Third Trimesters

The impact of dietary inflammatory potential on serum cytokine concentrations in second and third trimesters of Chinese pregnant women is not clear. A total of 175 pregnant women from the Tianjin Maternal and Child Health Education and Service Cohort (TMCHESC) were included. The dietary inflammatory index (DII) was calculated based on 24-h food records. Serum tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), IL-6, IL-8, IL-10, C-reactive protein (CRP), and monocyte chemoattractant protein-1 (MCP-1) levels in the second and third trimesters were measured. The mean DII scores (mean ± SD) were -0.07 ± 1.65 and 0.06 ± 1.65 in the second and third trimesters, respectively. In the third trimester, IL-1β (p = 0.039) and MCP-1 (p = 0.035) levels decreased and then increased with increasing DII scores. IL-10 concentrations decreased in pregnant women whose DII scores increased between the second and third trimesters (p = 0.011). Thiamin and vitamin C were negatively correlated with MCP-1 (β = -0.879, and β = -0.003) and IL-6 (β = -0.602, and β = -0.002) levels in the third trimester. In conclusion, the DII score had a U-shaped association with cytokine levels during the third trimester. Changes in DII scores between the second and third trimesters of pregnancy were correlated with cytokine levels during the third trimester.

IL-6 and IL-8: An Overview of Their Roles in Healthy and Pathological Pregnancies

Interleukin-6 (IL-6) is an acknowledged inflammatory cytokine with a pleiotropic action, mediating innate and adaptive immunity and multiple physiological processes, including protective and regenerative ones. IL-8 is a pro-inflammatory CXC chemokine with a primary function in attracting and activating neutrophils, but also implicated in a variety of other cellular processes. These two ILs are abundantly expressed at the feto-maternal interface over the course of a pregnancy and have been shown to participate in numerous pregnancy-related events. In this review, we summarize the literature data regarding their role in healthy and pathological pregnancies. The general information related to IL-6 and IL-8 functions is followed by an overview of their overall expression in cycling endometrium and at the feto-maternal interface. Further, we provide an overview of their involvement in pregnancy establishment and parturition. Finally, the implication of IL-6 and IL-8 in pregnancy-associated pathological conditions, such as pregnancy loss, preeclampsia, gestational diabetes mellitus and infection/inflammation is discussed.

Association between interleukin-6 levels in amniotic fluid after rupture of membranes during labour at term pregnancy and successful vaginal delivery: a prospective cohort study

We compared the mean interleukin-6 (IL-6) level in the amniotic fluid after rupture of membranes during labour at term pregnancy according to the delivery methods through prospective cohort study. Cases with premature rupture of membranes, multifetal pregnancy, and major congenital anomalies were excluded. Amniotic fluid was obtained from vaginal canal immediately after spontaneous rupture of membranes. A total of 47 cases were analysed, and 72.3% (34/47) had successful vaginal delivery. The mean concentration of IL-6 in the amniotic fluid was significantly higher in the vaginal delivery group than in the caesarean section group (5,229 pg/mL vs. 1,702 pg/mL, p = .022). The concentration of IL-6 from the amniotic fluid tended to increase as the cervical dilatation increased. The association between high IL-6 level (>2,500 pg/mL) and successful vaginal delivery was not significant after adjusting the degree of cervical dilatation in multivariate logistic regression analysis. IMPACT STATEMENTWhat is already known on this subject? Multiparity, active and strong uterine contractions, dilated cervical os, and the position of foetal head are known clinical factors affecting the successful vaginal delivery. There are few studies on markers for successful vaginal delivery in patients with labour.What do the results of this study add? The mean value of IL-6 concentration from the amniotic fluid collected from vagina immediately after rupture of membranes was significantly higher in the patients who had resulted in successful vaginal delivery than those who had failed.What are the implications are of these findings for clinical practice and/or further research? Measurement of IL-6 concentration in the amniotic fluid from vaginal canal in patients with labour might help to predict the successful vaginal delivery and shorten the time before decision of caesarean section.

Differences in maternal and neonatal cardiometabolic markers and placenta status by foetal sex. The GESTAFIT project

Aims:

To explore the differences in some maternal-neonatal metabolic markers and placenta status by foetal sex.

Methods:

One hundred thirty-nine Caucasian pregnant women from the GESTAFIT project and their new-borns were included in the present cross-sectional study. Serum cardiometabolic markers (i.e. lipid and glycaemic profile and uric acid) were analysed at late pregnancy and at birth. In placenta, telomeres length, proportion of deleted mitochondrial-DNA and mitochondrial-DNA density, some minerals and interleukin 8, epidermal growth factor, fibroblast growth factor-2 and vascular endothelial growth factor were measured. The study was run between November 2015 and April 2018.

Results:

Mothers carrying a male showed higher serum triglycerides than mothers carrying a female at late pregnancy (p < .05). Serum total and low-density lipoprotein cholesterol were greater in males’ umbilical cord blood artery compared to females’ new-borns (both, p < .05). Mothers of males and male new-borns presented higher uric acid than mothers of females and female new-borns at birth (p < .05). Female’s placentas presented greater placental-newborn weight ratio, manganese content and fibroblast growth factor-2 (all, p ⩽ .05), and evidence of statistical significance in telomeres length, which were 17% longer (p = .076).

Conclusion:

Our findings show weak differences in some cardiometabolic and placental status markers by foetal sex. Notwithstanding, we observed a slightly more proatherogenic profile in both, mothers carrying males’ foetuses and male new-borns. We also found lower serum uric acid and better placenta status in mothers carrying a female. These findings indicate that foetal sex might need to be considered for a more personalized follow-up of pregnancies.

The use of ultrasound, fibronectin and other parameters to predict the success of labour induction

Induction of labour is a common obstetrical procedure and is undertaken when the benefits of delivery are considered to outweigh the risks of continuation of pregnancy. However, more than one-fifth of induction cases fail to result in vaginal births and lead to unplanned caesarean deliveries, which compromise the birth experience and have negative clinical and resource implications. The need for accurate prediction of successful labour induction is increasingly recognised and many researchers have attempted to evaluate the potential predictability of different factors including maternal characteristics, Bishop score, various biochemical markers and ultrasound markers and derive predictive models to address this issue.

Cytokine Patterns in Maternal Serum From First Trimester to Term and Beyond

Pregnancy implies delicate immunological balance between two individuals, with constant changes and adaptions in response to maternal capacity and fetal demands. We performed cytokine profiling of 1149 longitudinal serum samples from 707 pregnant women to map immunological changes from first trimester to term and beyond. The serum levels of 22 cytokines and C-reactive protein (CRP) followed diverse but characteristic trajectories throughout pregnancy, consistent with staged immunological adaptions. Eotaxin showed a particularly robust decrease throughout pregnancy. A strong surge in cytokine levels developed when pregnancies progressed beyond term and the increase was amplified as labor approached. Maternal obesity, smoking and pregnancies with large fetuses showed sustained increase in distinct cytokines throughout pregnancy. Multiparous women had increased cytokine levels in the first trimester compared to nulliparous women with higher cytokine levels in the third trimester. Fetal sex affected first trimester cytokine levels with increased levels in pregnancies with a female fetus. These findings unravel important immunological dynamics of pregnancy, demonstrate how both maternal and fetal factors influence maternal systemic cytokines, and serve as a comprehensive reference for cytokine profiles in normal pregnancies.

STAT3 inhibition reduced PD-L1 expression and enhanced antitumor immune responses

Colon cancer is one the most common diagnosed cancers in America and Europe. Signal transducer and activator of transcription 3 (STAT3) in colon cancer is associated with proliferation of the tumor cells and suppression of immune responses. STAT3 activation upregulates the transcription of many suppressor genes, including programmed death-ligand 1 (PD-L1). This study was aimed to investigate the effect of STAT3 inhibition in a colon cancer cell line, HCT-15, and particularly in presence of samples obtained from the patients suffering from colon cancer. In this project, the expression of PD-L1 and apoptosis-related proteins were assessed following STAT3 inhibition, using FLLL32, in HCT-15 cells. To evaluate the effects of STAT3 inhibition on immune response, lymphocytes from 20 men with Stage III colon cancer and 20 healthy donors were cocultured with HCT-15 cells in presence or absence of STAT3 inhibitor. Then, T regulatory (T-reg) cell evaluation and intracellular cytokine staining (ICS) were performed using flowcytometry to assess the T-reg and T helper (Th) subset cytokines following STAT3 inhibition. STAT3 inhibition suppressed PD-L1 expression and induced apoptosis in HCT-15 cells. The population of T-reg cells in patients with colon cancer significantly decreased after treatment with STAT3 inhibitor. ICS revealed that STAT3 inhibition promotes Th1 protective immune responses. These findings suggest that STAT3 inhibition through either induction of apoptosis in the colon cancer cells and/or activation of efficient immune responses can lead to overcome cancer-induced immune tolerance.