Tissue-specific cytokine release from human extra-placental membranes stimulated by lipopolysaccharide in a two-compartment tissue culture system

Microbiome and Pregnancy Dysbiosis: A Narrative Review on Offspring Health

Background: Emerging evidence suggests that the maternal microbiome plays a crucial role in shaping fetal neurodevelopment, immune programming, and metabolic health. Dysbiosis during pregnancy-whether gastrointestinal, oral, or vaginal-can significantly influence pregnancy outcomes and long-term child health. Materials and Methods: The search was performed using databases such as PubMed, Scopus, and Google Scholar including research published from January 2000 to January 2025. The keywords used were "Fetal Programming", " Maternal Immune Activation", "Maternal microbiome", "Microbiota-Gut-Brain Axis", and "Pregnancy Dysbiosis". Results: The maternal microbiome undergoes substantial changes during pregnancy, with alterations in microbial diversity and function linked to conditions such as gestational diabetes, obesity, and preeclampsia. Pregnancy-related dysbiosis has been associated with adverse neurodevelopmental outcomes, including an increased risk of autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and cognitive impairments in offspring. Conclusions: Understanding the intricate relationship between maternal microbiota and fetal health is essential for developing targeted interventions. Personalized microbiome-based strategies, including dietary modifications and probiotic supplementation, hold promise in optimizing pregnancy outcomes and promoting health in offspring.

Use of an Eyelid Pressure Patch Concomitantly with a Decellularized Dehydrated Amniotic Membrane for Ocular Surface Disease Management

INTRODUCTION

Persistent corneal epithelial defects (PCEDs) occur when conditions like dry eye disease (DED), neurotrophic keratitis (NK), and limbal stem cell deficiency impair corneal healing, leading to risks of infection, scarring, or perforation. Decellularized, dehydrated pure amniotic membrane basement membrane (AMBM) supports healing by promoting cell adhesion, growth, and inflammation reduction. Eyelid pressure patching helps stabilize the AMBM, protects the cornea, and enhances its therapeutic effects.

METHODS

This retrospective study analyzed 144 eyes treated with either a single-layer or three-layer decellularized AMBM combined with a 24-h eyelid pressure patch.

RESULTS

Of the patients included, 90% received a single-layer AMBM and 10% a three-layer AMBM. In the single-layer group, 100% of cases showed complete healing and AMBM dissolution. In the three-layer group, 100% showed corneal staining improvement, but 20-30% of the AMBM remained undissolved. No patients reported experiencing pain, discomfort, or infection.

CONCLUSIONS

Combining eyelid pressure patching with amniotic membrane treatment is a safe and effective approach for healing persistent corneal epithelial defects.

Viral infections in etiology of mental disorders: a broad analysis of cytokine profile similarities - a narrative review

The recent pandemic caused by the SARS-CoV-2 virus and the associated mental health complications have renewed scholarly interest in the relationship between viral infections and the development of mental illnesses, a topic that was extensively discussed in the previous century in the context of other viruses, such as influenza. The most probable and analyzable mechanism through which viruses influence the onset of mental illnesses is the inflammation they provoke. Both infections and mental illnesses share a common characteristic: an imbalance in inflammatory factors. In this study, we sought to analyze and compare cytokine profiles in individuals infected with viruses and those suffering from mental illnesses. The objective was to determine whether specific viral diseases can increase the risk of specific mental disorders and whether this risk can be predicted based on the cytokine profile of the viral disease. To this end, we reviewed existing literature, constructed cytokine profiles for various mental and viral diseases, and conducted comparative analyses. The collected data indicate that the risk of developing a specific mental illness cannot be determined solely based on cytokine profiles. However, it was observed that the combination of IL-8 and IL-10 is frequently associated with psychotic symptoms. Therefore, to assess the risk of mental disorders in infected patients, it is imperative to consider the type of virus, the mental complications commonly associated with it, the predominant cytokines to evaluate the risk of psychotic symptoms, and additional patient-specific risk factors.

Leveraging bioengineering to assess cellular functions and communication within human fetal membranes

The fetal membranes enclose the growing fetus and amniotic fluid. Preterm prelabor rupture of fetal membranes is a leading cause of preterm birth. Fetal membranes are composed of many different cell types, both structural and immune. These cells must coordinate functions for tensile strength and membrane integrity to contain the growing fetus and amniotic fluid. They must also balance immune responses to pathogens with maintaining maternal-fetal tolerance. Perturbation of this equilibrium can lead to preterm premature rupture of membranes without labor. In this review, we describe the formation of the fetal membranes to orient the reader, discuss some of the common forms of communication between the cell types of the fetal membranes, and delve into the methods used to tease apart this paracrine signaling within the membranes, including emerging technologies such as organ-on-chip models of membrane immunobiology.

Compartmentalized Innate Immune Response of Human Fetal Membranes against Escherichia coli Choriodecidual Infection

An infectious process into the uterine cavity represents a major endangered condition that compromises the immune privilege of the maternal-fetal unit and increases the risk for preterm birth (PTB) and premature rupture of membranes (PROM). Fetal membranes are active secretors of antimicrobial peptides (AMP), which limit bacterial growth, such as Escherichia coli. Nevertheless, the antibacterial responses displayed by chorioamniotic membranes against a choriodecidual E. coli infection have been briefly studied. The objective of this research was to characterize the profile of synthesis, activity, and spatial distribution of a broad panel of AMPs produced by fetal membranes in response to E. coli choriodecidual infection. Term human chorioamniotic membranes were mounted in a two independent compartment model in which the choriodecidual region was infected with live E. coli (1 × 10⁵ CFU/mL). Amnion and choriodecidual AMP tissue levels and TNF-α and IL-1β secretion were measured by the enzyme-linked immunosorbent assay. The passage of bacterium through fetal membranes and their effect on structural continuity was followed for 24 h. Our results showed that E. coli infection caused a progressive mechanical disruption of the chorioamniotic membranes and an activated inflammatory environment. After the challenge, the amnion quickly (2-4 h) induced production of human beta defensins (HBD)-1, HBD-2, and LL-37. Afterwards (8-24 h), the amnion significantly produced HBD-1, HBD-2, HNP-1-3, S100A7, sPLA2, and elafin, whereas the choriodecidua induced LL-37 synthesis. Therefore, we noticed a temporal- and tissue-specific pattern regulation of the synthesis of AMPs by infected fetal membranes. However, fetal membranes were not able to contain the collagen degradation or the bacterial growth and migration despite the battery of produced AMPs, which deeply increases the risk for PTB and PROM. The mixture of recombinant HBDs at low concentrations resulted in increased bactericidal activity compared to each HBD alone in vitro, encouraging further research to study AMP combinations that may offer synergy to control drug-resistant infections in the perinatal period.

Prolactin Protects the Structural Integrity of Human Fetal Membranes by Downregulating Inflammation-induced Secretion of Matrix Metalloproteinases

Prolactin (PRL) is a pleiotropic hormone with a key role in pregnancy. In fetal membranes, PRL can regulate the secretion of pro-inflammatory factors, which induces the activation of matrix metalloproteinases (MMPs). The increase and activation of MMPs deregulate the turnover of the extracellular matrix in the fetal membranes, altering its structure and function, causing premature rupture of the membranes and preterm labor. In this work, we evaluate the effect of PRL upon the secretion of MMP-1, MMP-2, MMP-9, MMP-13, and the tissue inhibitors of metalloproteinases (TIMPs) in human fetal membranes after lipopolysaccharide (LPS) challenge. Nine fetal membranes from healthy non-laboring cesarean deliveries at term were cultured in a 2-independent chamber system and pre-treated with 250, 500, 1000 or 4000 ng/ml of PRL for 24 h, then choriodecidual region was stimulated with 500 ng/ml of LPS plus fresh PRL for 24 h. The MMPs and TIMPs secretion were quantified by ELISA, additionally MMP-2 and MMP-9 gelatinolytic activity was measured by zymography. LPS induced the MMP-9 and MMP-1 secretion, but no MMP-2 or MMP-13 in comparison with basal levels. PRL co-treatment decreased the MMP-2, MMP-9 and MMP-1 secretion induced by LPS. The active forms were present in the tissue extract, showing a response consistent with the secretion profile. TIMP-1 and TIMP-2 secretion was decreased after LPS treatment and the PRL co-treatment reverts this effect. The present results support that PRL may favor the balance between these factors involved in the structural maintenance of fetal membranes in an inflammatory event.

Management of Persistent Corneal Epithelial Defects with Human Amniotic Membrane-derived Dry Matrix

Objective

To report the outcomes of using human amniotic membrane-derived dry matrix (AMDDM) in the management of persistent corneal epithelial defects (PEDs) of various etiologies.

Methods

A cohort study of 84 patients age range 7 to 92 years with 93 PEDs were treated with AMDDM (Omnigen^® using OmniLenz^® at two centers (Queen Victoria Hospital and Maidstone Hospital) in the UK. The main outcome measures were healing response of PED and time to heal after application of AMDDM.

Results

A total of 106 applications of AMDDM were recorded for 81 patients (52 males, 29 females) with a spectrum of different etiologies. Fifty-eight percent of the eyes showed complete healing, and 28% showed partial decrease of the size of PEDs with average treatment length recorded as 22.4±12.3 days. In patients with limbal stem cell deficiency (n=44; aniridia=12, chemical injury=9, Stevens–Johnson syndrome=10), 50% of PEDs showed complete healing and 27% showed partial healing. In patients with microbial keratitis (n=21) (bacterial: 13, fungal: 4, herpetic: 3, acanthamoeba: 1) 57% of PEDs showed complete healing and 33% were partially healed. In patients with keratoplasty (n=16), 56% of PEDs showed complete healing and 31% were partially healed. Vision remained stable in 59% and improved in 27% of the study the population.

Conclusion

AMDDM can be easily applied in the clinical setting and has demonstrated its efficiency as a new tool to treat persistent epithelial defects.

Prolactin modifies the in vitro LPS-induced chemotactic capabilities in human fetal membranes at the term of gestation

Problem

Immune responses of fetal membranes involve the production of chemoattractant mediators causing infiltration of maternal and fetal leukocytes, intrauterine inflammation and potentially the disruption of maternal‐fetal tolerance. Prolactin (PRL) has deep immunoregulatory effects in the fetal‐maternal interface. We aimed to test the in vitro PRL effect upon chemotactic capacities of human fetal membranes.

Method of Study

Fetal membranes and umbilical cord blood were collected from healthy non‐laboring caesarean deliveries at term. Fetal membranes were cultured in Transwell® frames to mimic the barrier function between choriodecidual and amniotic sides. Tissues were treated with PRL, Lipopolysaccharide (LPS), or both simultaneously. Then, RANTES, MCP‐1, MIP‐1α, IP‐10, and PECAM‐1 were quantified in a conditioned medium by choriodecidual or amniotic sides. The chemotaxis of subsets of migrating mononuclear cells from umbilical cord blood was evaluated in a Boyden Chamber in response to the conditioned medium by both sides.

Results

Lipopolysaccharide stimulates the production of RANTES, MCP‐1, MIP‐1α, and PECAM‐1 in choriodecidua, while MIP‐1α and PECAM‐1 only increase in amnion. PRL decrease RANTES, MCP‐1, and MIP‐1 only in choriodecidua, but PECAM‐1 was decreased mainly in amnion. The leukocyte migration was regulated significantly in response to the conditioned medium by the amnion, increase in the conditioned medium after LPS treatment, contrary with, the leukocyte migration decreased in a significant manner in response to conditioned medium after PRL and LPS‐PRL co‐treatment. Finally, T cells were the most responsive subset of cells.

Conclusions

Prolactin modified in a tissue‐specific manner the chemotactic factor and the leukocyte migration differentially in fetal membranes.

Distinct preterm labor phenotypes have unique inflammatory signatures and contraction associated protein profiles†

Preterm labor (PTL) is the predominant cause of childhood morbidity and mortality. It has several phenotypes, each with a distinct etiology often involving inflammation. Here, in samples of reproductive tissues obtained in early PTL from women with phenotypically defined PTL, we examined the presence and distribution of inflammation and its relationship with prolabor gene expression. In chorioamnionitis (CA-PTL), cytokine protein concentrations were increased across all tissues; in idiopathic (I-PTL), the inflammatory changes were limited to the choriodecidua; inflammation was not a feature of placental abruption (PA-PTL). CA-PTL was associated with activation of p65 in the myometrium and AP-1 in the choriodecidua, and PA-PTL with CREB in the choriodecidua. In the myometrium, PGHS-2 mRNA level was increased in CA- and I-PTL; in the amnion, PGHS-2 mRNA level was higher in PA- and I-PTL, while in CA-PTL, OT, OTR mRNA, and CX-43 expression were increased. In the choriodecidua, PGHS-2 mRNA level was unchanged, but in CA and I-PTL, OT mRNA level were increased and OTR was reduced. These data show that CA-PTL is associated with widespread inflammation and prolabor gene expression. In contrast, in I-PTL, inflammation is limited to the choriodecidua, with discrete increases in PGHS-2 in the amnion and OT in the choriodecidua. Inflammation is not a feature of PA-PTL, which is associated with increased OT and OTR in the amnion.

Regulation of ERK1/2 and SMAD2/3 Pathways by Using Multi-Layered Electrospun PCL-Amnion Nanofibrous Membranes for the Prevention of Post-Surgical Tendon Adhesion

Background

Adhesion after tendon injury is a common complication in clinical practice. The lack of effective prevention mechanisms seriously affects the functional rehabilitation of patients. This research aimed to optimise the amniotic membrane and explain the mechanism of tendon–amniotic membrane by imitating the tendon sheath to construct a multilayer electrospun polycaprolactone (PCL) nanofibre membrane.

Materials and Methods

Fresh amnions were subjected to freezing and vacuum drying. The two surfaces of freeze-dried amnions were coated with PCL nanofibres by electrospinning, thereby forming a multilayer composite membrane and constructing a growth factor-sustained release system conforming to the tendon-healing cycle. The new materials were characterised, and the biological effects on tenocytes and fibroblasts were evaluated. The tendon injury model of New Zealand rabbits was constructed to observe the effects on tendon adhesion and healing.

Results

After freezing and vacuum drying, fresh amnions were found to effectively remove most of the cell components but retained the active components TGF-β1, bFGF, VEGF, and PDGF, as well as the fibrous reticular structure of the basement membrane. After coating with PCL nanofibres, a composite membrane mimicking the structure of the tendon sheath was constructed, thereby strengthening the tensile strength of the amnion. By up-regulating the phosphorylation of ERK1/2 and SMAD2/3, the adhesion and proliferation of tenocytes and fibroblasts were promoted, and collagen synthesis was enhanced. In the rabbit tendon repair model, the composite membrane effectively isolated the exogenous adhesion tissue and promoted endogenous tendon healing.

Conclusion

The composite membrane mimicking the structure of tendon sheath effectively isolated the exogenous adhesion tissue and achieved good tendon slip. By slowly releasing the growth factors TGF-β1, bFGF, VEGF and PDGF, the ERK1/2 and SMAD2/3 pathways were regulated. Consequently, endogenous tendon healing was promoted. This strategy can alternatively address the clinical problem of tendon adhesion.

Group B streptococcus activates transcriptomic pathways related to premature birth in human extraplacental membranes in vitro

Streptococcus agalactiae (group B streptococcus [GBS]) infection in pregnant women is the leading cause of infectious neonatal morbidity and mortality in the United States. Although inflammation during infection has been associated with preterm birth, the contribution of GBS to preterm birth is less certain. Moreover, the early mechanisms by which GBS interacts with the gestational tissue to affect adverse pregnancy outcomes are poorly understood. We hypothesized that short-term GBS inoculation activates pathways related to inflammation and premature birth in human extraplacental membranes. We tested this hypothesis using GBS-inoculated human extraplacental membranes in vitro. In agreement with our hypothesis, a microarray-based transcriptomics analysis of gene expression changes in GBS-inoculated membranes revealed that GBS activated pathways related to inflammation and preterm birth with significant gene expression changes occurring as early as 4 h postinoculation. In addition, pathways related to DNA replication and repair were downregulated with GBS treatment. Conclusions based on our transcriptomics data were further supported by responses of prostaglandin E2 (PGE2), and matrix metalloproteinases 1 (MMP1) and 3 (MMP3), all of which are known to be involved in parturition and premature rupture of membranes. These results support our initial hypothesis and provide new information on molecular targets of GBS infection in human extraplacental membranes.

Preclinical evaluation of drugs to block inflammation-driven preterm birth

Intrauterine inflammation, the major cause of early preterm birth, can have microbial and sterile aetiologies. We assessed in a Transwell model the anti-inflammatory efficacies of five drugs on human extraplacental membranes delivered after preterm spontaneous labour (30-34 wk). Drugs [TPCA1 (IKKβ inhibitor), 5 z-7-oxozeaenol (OxZ, TAK1 inhibitor), inhibitor of NF-κB essential modulator binding domain (iNBD), SB239063 (p38 MAPK inhibitor) and N-acetyl cysteine (free radical scavenger free radicals)] were added after 12 h equilibration to the amniotic compartment. Concentrations of IL-6, TNF-α, MCP-1, IL-1β and PGE₂ in the media, and IL6, TNFA and PTGS2 mRNA expression levels in membranes, were determined after 12 h. Data were analysed using mixed models analyses. Thirteen of the 28 membranes had histological chorioamnionitis (HCA⁺); five were positive for bacterial culture and six for fetal inflammatory reaction. Baseline PGE₂ and cytokine production was similar between HCA^- and HCA⁺ membranes. Anti-inflammatory effects were also similar between HCA^- and HCA⁺ membranes. TPCA1 and OxZ were the most effective drugs; each inhibited amniotic secretion of 4/5 pro-inflammatory mediators and mRNA levels of 2/3, regardless of stimulus. We conclude that treatment with TPCA1 or OxZ, in combination with antibiotics, may minimise the adverse effects of intrauterine inflammation in pregnancy.

The physiology of fetal membrane weakening and rupture: Insights gained from the determination of physical properties revisited

Rupture of the fetal membranes (FM) is precipitated by stretch forces acting upon biochemically mediated, pre-weakened tissue. Term FM develop a para-cervical weak zone, characterized by collagen remodeling and apoptosis, within which FM rupture is thought to initiate. Preterm FM also have a weak region but are stronger overall than term FM. Inflammation/infection and decidual bleeding/abruption are strongly associated with preterm premature FM rupture (pPROM), but the specific mechanisms causing FM weakening-rupture in pPROM are unknown. There are no animal models for study of FM weakening and rupture. Over a decade ago we developed equipment and methodology to test human FM strength and incorporated it into a FM explant system to create an in-vitro human FM weakening model system. Within this model TNF (modeling inflammation) and Thrombin (modeling bleeding) both weaken human FM with concomitant up regulation of MMP9 and cellular apoptosis, mimicking the characteristics of the spontaneous FM rupture site. The model has been enhanced so that test agents can be applied directionally to the choriodecidual side of the FM explant consistent with the in-vivo situation. With this enhanced system we have demonstrated that the pathways involving inflammation/TNF and bleeding/Thrombin induced FM weakening overlap. Furthermore GM-CSF production was demonstrated to be a critical common intermediate step in both the TNF and the Thrombin induced FM weakening pathways. This model system has also been used to test potential inhibitors of FM weakening and therefore pPROM. The dietary supplement α-lipoic acid and progestogens (P4, MPA and 17α-hydroxyprogesterone) have been shown to inhibit both TNF and Thrombin induced FM weakening. The progestogens act at multiple points by inhibiting both GM-CSF production and GM-CSF action. The use of a combined biomechanical/biochemical in-vitro human FM weakening model system has allowed the pathways of fetal membrane weakening to be delineated, and agents that may be of clinical use in inhibiting these pathways to be tested.

An animal model for chorioamnionitis at term

OBJECTIVE

The purpose of this study was to develop an animal model for intrapartum inflammation at term to investigate the interactions between maternal and fetal inflammatory responses and adverse neurologic outcome.

STUDY DESIGN

Lipopolysaccharide (160, 320, or 640 μg/kg) was administered intraperitoneally to day 20 term-pregnant Sprague Dawley rat dams 2, 4, and 6 hours before sample collection. Maternal outcomes included dam core temperature and plasma interleukin 6 (IL-6). Fetal outcomes included plasma IL-6, brain IL-6 messenger RNA expression, and brain IL-6 protein expression. Primary cortical cell cultures were prepared to examine neuronal morphologic condition. Neurite counts were obtained with the use of automated Sholl analysis.

RESULTS

Maternal plasma IL-6 levels peaked 2 hours after lipopolysaccharide stimulus and rapidly resolved, except for an observed low level persistence at 6 hours with 640 μg/kg. Fetal plasma and placental IL-6 expression also peaked rapidly but only persisted in placental samples. Fetal brain IL-6 RNA and protein expression was significantly higher than control litters at 6 hours after the exposure to both 320 μg/kg (P ≤ .05) and 640 μg/kg (P ≤ .01). Cortical cells from fetuses that were exposed for 6 hours to maternal systemic inflammation showed reduced neurite number and neurite length (P < .001) with increasing lipopolysaccharide dose.

CONCLUSION

Our results demonstrate that fetal brain injury follows isolated systemic maternal inflammation and that fetal brain inflammation lags after maternal stimulus, which creates a potential 4-hour clinical window for therapeutic intervention.

Caspase-1-mediated cytokine release from gestational tissues, placental, and cord blood

Distinguishing between fetal and maternal inflammatory responses is necessary for understanding the immune interplay either side of the placenta. Fetal immunity reaches maturity during extrauterine life and while basic inflammatory responses afford a certain degree of protection, fetuses are vulnerable to infection. With the discovery of inflammasomes—intracellular scaffolds that facilitate the elaboration of reactions resulting in the release of mature interleukin-1β (IL-1β)—it is necessary to consider how inflammatory stimuli are processed. The purinergic P2X₇ receptor located on haematopoietic cells is a key intermediary in signal transduction initiated at Toll-like receptors (TLR) terminating in release of the mature IL-1β product. We demonstrate herein that IL-1β release from fetal membranes and mononuclear cells isolated from cord, placental, and maternal blood, obtained at term, is P2X₇- and caspase-1 dependent. The P2X₇-dependent release of the cytokine, which was highest from choriodecidua, was attenuated by progesterone (P4), prolactin and an NFkB inhibitor. The NLRP3 inflammasome appears necessary for the processing of IL-1β in gestational tissues and leukocytes.

The trichloroethylene metabolite S-(1,2-dichlorovinyl)-l-cysteine but not trichloroacetate inhibits pathogen-stimulated TNF-α in human extraplacental membranes in vitro

Extraplacental membranes define the gestational compartment and provide a barrier to infectious microorganisms ascending the gravid female reproductive tract. We tested the hypothesis that bioactive metabolites of trichloroethylene (TCE) decrease pathogen-stimulated innate immune response of extraplacental membranes. Extraplacental membranes were cultured for 4, 8, and 24h with the TCE metabolites trichloroacetate (TCA) or S-(1,2-dichlorovinyl)-l-cysteine (DCVC) in the absence or presence of lipoteichoic acid (LTA) or lipopolysaccharide (LPS) to simulate infection. In addition, membranes were cocultured with DCVC and Group B Streptococcus (GBS). DCVC (5-50μM) significantly inhibited LTA-, LPS-, and GBS-stimulated cytokine release from tissue cultures as early as 4h (P≤0.05). In contrast, TCA (up to 500μM) did not inhibit LTA-stimulated cytokine release from tissue punches. Because cytokines are important mediators for host response to infectious microorganisms these findings suggest that TCE exposure could potentially modify susceptibility to infection during pregnancy.

Evidence of an immunosuppressive effect of progesterone upon in vitro secretion of proinflammatory and prodegradative factors in a model of choriodecidual infection

OBJECTIVE

To evaluate whether progesterone (P4) is able to modulate the secretion of tumour necrosis factor α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8, IL-10 and matrix metalloproteinase-9 (MMP-9) after choriodecidual stimulation with lipopolysaccharide (LPS).

DESIGN

Chorioamnionitis-elicited preterm delivery is associated with an uncontrolled secretion of proinflammatory cytokines that may induce MMPs, which modify the fine immunological and structural equilibrium at the fetal-maternal interface.

SETTING

Instituto Nacional de Perinatología 'Isidro Espinosa de los Reyes', Mexico City.

SAMPLE

Twelve human fetal membranes at term from healthy patients were placed in a two-chamber culture system.

METHODS

Choriodecidual and amniotic regions were preincubated with 1.0, 0.1, or 0.01 μmol/l P4 for 24 hours; after which the choriodecidual region was costimulated with 1000 ng/ml of LPS for 24 hours.

MAIN OUTCOME MEASURES

Descriptive statistics were obtained for each variable. Data distribution was tested for normality using Kolmogorov-Smirnoff and Shapiro-Wilk tests. When distribution was normal, Student's t test was used to analyse for differences among groups. Mann-Whitney's U test was used when data were not normally distributed.

RESULTS

Pretreatment with 1.0 μmol/l P4 significantly blunted the secretion of TNF-α, IL-1β, IL-6, IL-8 and IL-10. MMP-9 was inhibited with 0.1 μmol/l P4. Mifepristone (RU486) blocked the immunosuppressive effect of P4, suggesting a P4 effect mediated by its receptor.

CONCLUSION

These results offer evidence to support the concept that P4 can protect the fetal-placental unit through a compensatory mechanism that partially limits the secretion of proinflammatory and prodegradative modulators.

Decidual GM-CSF is a critical common intermediate necessary for thrombin and TNF induced in-vitro fetal membrane weakening

INTRODUCTION

Inflammation/infection and decidual bleeding/abruption are highly associated with pPROM. As no animal model for pPROM exists, we have developed an in-vitro model system for the study of human fetal membrane (FM) weakening/rupture. Using it we have demonstrated that both TNF/IL-1 (modeling inflammation) and thrombin (modeling bleeding) weaken full thickness FM in a dose dependent manner concomitant with inducing biochemical changes similar to those seen in the FM physiological weak zone.

METHODS

As the physiological site of infection and bleeding is the choriodecidua (CD), we modified our model system with full thickness FM tissue mounted on modified Transwell culture inserts to permit directional TNF/thrombin exposure on the decidua only (rather than both sides of the FM). After incubation, medium was sampled separately from the CD facing (maternal side) or from the amnion facing (fetal side) compartments and probed for cytokine release and confirmed with western blots. The FM was strength tested within the insert.

RESULTS

Full-thickness FM fragments exposed to TNF or thrombin on CD side only showed dose dependent weakening and biochemical changes consistent with previous reports. Concomitantly, GM-CSF increased markedly on the CD but not the amnion side. Numerous proteases including MMP1 and MMP3 also increased on the CD side. Pre-incubation with GM-CSF antibody blocked both thrombin and TNF induced weakening. Finally, GM-CSF weakened FM in a dose dependent manner.

DISCUSSION

GM-CSF is a critical common intermediate in the thrombin and TNF FM weakening pathways.

Human fetal membranes generate distinct cytokine profiles in response to bacterial Toll-like receptor and nod-like receptor agonists

Bacterial infection-associated inflammation is thought to be a major cause of preterm premature rupture of membranes. Proinflammatory cytokines, such as interleukin 1B (IL1B), can weaken fetal membranes (FM) by upregulating matrix metalloproteinases and inducing apoptosis. The mechanism by which infection leads to inflammation at the maternal-fetal interface and subsequent preterm birth is thought to involve innate immune pattern recognition receptors (PRR), such as the Toll-like receptors (TLR) and Nod-like receptors (NLR), which recognize pathogen-associated molecular patterns (PAMPs). The objective of this study was to determine the cytokine profile generated by FMs in response to the bacterial TLR and NLR agonists peptidoglycan (PDG; TLR2), lipopolysaccharide (LPS; TLR4), flagellin (TLR5), CpG ODN (TLR9), iE-DAP (Nod1), and MDP (Nod2). PDG, LPS, flagellin, iE-DAP, and MDP triggered FMs to generate an inflammatory response, but the cytokine profiles were distinct for each TLR and NLR agonist, and only IL1B and RANTES were commonly upregulated in response to all five PAMPs. CpG ODN, in contrast, had a mild stimulatory effect only on MCP-1 and primarily downregulated basal FM cytokine production. IL1B secretion induced by PDG, LPS, flagellin, iE-DAP, and MDP was associated with its processing. Furthermore, FM IL1B secretion in response to TLR2, TLR4, and TLR5 activation was caspase 1-dependent, whereas Nod1 and Nod2 induced IL1B secretion independent of caspase 1. These findings demonstrate that FMs respond to different bacterial TLR and NLR PAMPs by generating distinct inflammatory cytokine profiles through distinct mechanisms that are specific to the innate immune PRR activated.

Tissue-specific IL-10 secretion profile from term human fetal membranes stimulated with pathogenic microorganisms associated with preterm labor in a two-compartment tissue culture system

OBJECTIVE

Interleukin (IL)-10 is a cytokine with anti-inflammatory properties that plays pivotal roles in immune recognition and maintenance of pregnancy, limiting the harmful effects of pro-inflammatory modulators. The aim of this work was to characterize the contribution of amnion and choriodecidua regions of the human fetal membranes in the production of IL-10 after selective stimulation with Candida albicans, Gardnerella vaginalis and Streptococcus agalactiae.

METHODS

Pre-labor human fetal membranes were cultured in a two-compartment tissue culture system and stimulated with 1 × 10(6) CFU/ml of each pathogen added to either the amniotic or choriodecidual region or both.

RESULTS

Candida albicans and G. vaginalis were the pathogens most effective in inducing IL-10 secretion, increasing 20 and 10 times, respectively, the levels of this cytokine in the choriodecidual compartment. Stimulation with S. agalactiae was effective only in the choriodecidual region, increasing two times IL-10 concentration.

CONCLUSIONS

Synthesis and secretion of IL-10 in response to three different pathogens associated with intrauterine infection and preterm birth are differential and depend on the nature of the microorganism and initial contact region.

Augmented dried versus cryopreserved amniotic membrane as an ocular surface dressing

Purpose

Dried amniotic membrane (AM) can be a useful therapeutic adjunct in ophthalmic surgery and possesses logistical advantages over cryopreserved AM. Differences in preservation techniques can significantly influence the biochemical composition and physical properties of AM, potentially affecting clinical efficacy. This study was established to investigate the biochemical and structural effects of drying AM in the absence and presence of saccharide lyoprotectants and its biocompatibility compared to cryopreserved material.

Methods

AM was cryopreserved or dried with and without pre-treatment with trehalose or raffinose and the antioxidant epigallocatechin (EGCG). Structural and visual comparisons were assessed using electron microscopy. Localisation, expression and release of AM biological factors were determined using immunoassays and immunofluorescence. The biocompatibility of the AM preparations co-cultured with corneal epithelial cell (CEC) or keratocyte monolayers were assessed using cell proliferation, cytotoxicity, apoptosis and migration assays.

Results

Drying devitalised AM epithelium, but less than cryopreservation and cellular damage was reduced in dried AM pre-treated with trehalose or raffinose. Dried AM alone, and with trehalose or raffinose showed greater factor retention efficiencies and bioavailability compared to cryopreserved AM and demonstrated a more sustained biochemical factor time release in vitro. Cellular health assays showed that dried AM with trehalose or raffinose are compatible and superior substrates compared to cryopreserved AM for primary CEC expansion, with increased proliferation and reduced LDH and caspase-3 levels. This concept was supported by improved wound healing in an immortalised human CEC line (hiCEC) co-cultured with dried and trehalose or raffinose membranes, compared to cryopreserved and fresh AM.

Conclusions

Our modified preservation process and our resultant optimised dried AM has enhanced structural properties and biochemical stability and is a superior substrate to conventional cryopreserved AM. In addition this product is stable and easily transportable allowing it to be globally wide reaching for use in clinical and military sectors.

Antimicrobial peptide response to group B Streptococcus in human extraplacental membranes in culture

OBJECTIVE

Streptococcus agalactiae (GBS) is an important cause of chorioamnionitis. This study characterizes GBS colonization and stimulation of antimicrobial responses in human extraplacental membranes using an ex vivo transwell two-compartment system of full-thickness membranes and live GBS.

STUDY DESIGN

Human extraplacental membranes were affixed to transwell frames (without synthetic membranes). Live GBS was added to the decidual side of membranes in transwell cultures, and cocultures were incubated for 4, 8 and 24 h. GBS recovery from homogenized membranes and culture medium was determined by enumerating colony forming units (CFU) on blood agar. Antimicrobial peptide expression was identified using immunohistochemistry and ELISA. GBS killing by HBDs was assessed in vitro by incubating GBS with different human beta defensins (HBDs) for 3 h, then enumerating CFU.

RESULTS

GBS recovery from membranes markedly decreased over time (P < 0.05). The antimicrobial peptides HBD-1, HBD-2, HBD-3, and lactoferrin were expressed in both GBS-exposed and non-exposed tissues. Notably, a pattern of localized increased HBD-2 in the amnion of GBS-infected tissue was observed. Moreover, GBS-treated membranes released increased amounts of HBD-2 into the amniotic and decidual compartments of the transwell cultures after 24 h (P < 0.05). In bacterial cultures, HBD-2 decreased GBS viability in a concentration-dependent manner (P < 0.05).

CONCLUSION

Innate immune responses in ex vivo human extraplacental membranes suppress GBS growth. HBD-2 was implicated in this GBS suppression with evidence of signal transduction across the tissue. Antimicrobial peptides may be important for innate immune defense against intrauterine GBS infections during pregnancy.

Tissue-specific human beta-defensins (HBD)-1, HBD-2 and HBD-3 secretion profile from human amniochorionic membranes stimulated with Candida albicans in a two-compartment tissue culture system

BACKGROUND

During intrauterine infection, amniochorionic membranes represent a mechanical and immunological barrier against dissemination of infection. Human beta defensins (HBD)-1, HBD-2, and HBD-3 are key elements of innate immunity that represent the first line of defense against different pathogen microorganisms associated with preterm labor. The aim of this work was to characterize the individual contribution of the amnion (AMN) and choriodecidua (CHD) regions to the secretion of HBD-1, HBD-2 and HBD-3, after stimulation with Candida albicans.

METHODS

Full-thickness human amniochorionic membranes were obtained after delivery by elective cesarean section from women at 37-40 wk of gestation with no evidence of active labor. The membranes were cultured in a two-compartment experimental model in which the upper compartment is delimited by the amnion and the lower chamber by the choriodecidual membrane. One million of Candida albicans were added to either the AMN or the CHD face or to both and compartmentalized secretion profiles of HBD-1, HBD-2, and HBD-3 were quantified by ELISA. Tissue immunolocalization was performed to detect the presence of HBD-1, -2, -3 in tissue sections stimulated with Candida albicans.

RESULTS

HBD-1 secretion level by the CHD compartment increased 2.6 times (27.30 [20.9-38.25] pg/micrograms protein) when the stimulus with Candida albicans was applied only on this side of the membrane and 2.4 times (26.55 [19.4-42.5] pg/micrograms protein) when applied to both compartments simultaneously. HBD-1 in the amniotic compartment remained without significant changes. HBD-2 secretion level increased significantly in the CHD when the stimulus was applied only to this region (2.49 [1.49-2.95] pg/micrograms protein) and simultaneously to both compartments (2.14 [1.67- 2.91] pg/micrograms protein). When the stimulus was done in the amniotic compartment HBD-2 remained without significant changes in both compartments. HBD-3 remained without significant changes in both compartments regardless of the stimulation modality. Localization of immune-reactive forms of HBD-1, HBD-2, and HBD-3 was carried out by immunohistochemistry confirming the cellular origin of these peptides.

CONCLUSION

Selective stimulation of amniochorionic membranes with Candida albicans resulted in tissue-specific secretion of HBD-1 and HBD-2, mainly in the CHD, which is the first region to become infected during an ascending infection.

A novel antiinflammatory role for the short-chain fatty acids in human labor

Human parturition is an inflammatory process that can be activated prematurely by pathological stimuli. This study investigated the expression of G protein-coupled receptors GPR43 and GPR41 receptors in human uteroplacental tissues and the role of short-chain fatty acids (SCFA) in modulating inflammatory pathways in fetal membranes. Expression of GPR43 and GPR41 was investigated in uteroplacental tissues collected from women delivering at term or preterm after ethical approval and patient informed consent. The effect of SCFA on expression of inflammatory genes was assessed in amnion explants after culture with a mimetic of infection (lipopolysaccharide, LPS). Sodium propionate effect on LPS-induced neutrophil chemotaxis was evaluated by transwell assay. GPR43 and GPR41 mRNA expression was higher in myometrium and fetal membranes collected from women after the onset of labor. GPR43 protein expression localized to immune cells and vascular endothelium in the myometrium and epithelium of fetal membranes. Treatment with LPS significantly increased mRNA expression of GPR43 and inflammatory genes. Cotreatment with LPS and sodium propionate decreased LPS-induced expression of inflammatory genes including IL-6, IL-8, cyclooxygenase-2, IL-1α, intercellular adhesion molecule-1, and platelet endothelial cell adhesion molecule-1 but not IL-1β or lymphocyte function-associated antigen-1. Sodium propionate reduced LPS-induced neutrophil chemotaxis and protein secretion of the neutrophil chemoattractant IL-8. Finally, fetal membrane expression of GPR43 was significantly higher in women delivering preterm with evidence of infection. GPR43-SCFA interactions may represent novel pathways that regulate inflammatory processes involved in human labor. Suppression of inflammatory pathways by SCFA may be therapeutically beneficial for pregnant women at risk of pathogen-induced preterm delivery.

In vitro secretion profile of pro-inflammatory cytokines IL-1β, TNF-α, IL-6, and of human beta-defensins (HBD)-1, HBD-2, and HBD-3 from human chorioamniotic membranes after selective stimulation with Gardnerella vaginalis

PROBLEM

Preterm labor associated with infection is a major clinical condition; in this work, we analyze the response of human chorioamniotic membranes stimulated with Gardnerella vaginalis.

METHOD OF STUDY

Using a two-compartment experimental model, 1 × 10(6) CFU/mL of G. vaginalis were added to either the amnion or choriodecidua face or to both. Concentrations of IL-1β, TNF-α, and IL-6, as well as human beta defensins (HBD) 1-3 were quantified by ELISA.

RESULTS

In comparison with control conditions and regardless of the stimulation modality, IL-1β and IL-6 increased 4-fold and 28-fold, respectively, in the choriodecidual compartment. HBD-1 increased 2-fold mainly in the amniotic compartment when the stimulus was applied directly to this region. HBD-2 and HBD-3 increased an average of 2- and 8-fold, respectively, in the choriodecidual region.

CONCLUSIONS

Stimulation with G. vaginalis induced a tissue-specific secretion profile of 1L-1β, IL-6, and HBD 1-3 in the chorioamniotic membranes.

Evidence of in vitro differential secretion of human beta-defensins-1, -2, and -3 after selective exposure to Streptococcus agalactiae in human fetal membranes

OBJECTIVE

The aim of this work was to characterize the individual contribution of the amnion (AMN) and choriodecidua (CHD) regions to the secretion of human beta defensins (HBD)-1, -2, and -3, after stimulation with Streptococcus agalactiae.

METHODS

Full-thickness membranes were mounted on a Transwell device, constituted by two independent chambers; 1 × 10(6) CFU/ml of S. agalactiae were added to either the AMN or CHD face or to both. Secretion profiles of HBD-1, HBD-2, and HBD-3 to the culture medium were quantified by enzyme-linked immunosorbent sandwich assay (ELISA).

RESULTS

Secretion profile of HBD-1 remained without significant changes; HBD-2 secretion level by the CHD increased 2.0 (2.73 ± 0.19 pg/μg) and 2.6 (3.62 ± 0.60 pg/μg) times when the stimulus was applied only to the CHD region and simultaneously to both compartments, respectively. The bacterial stimulation in the AMN induced a 2.0 times (2.06 ± 0.29 pg/μg) increase in this region. HBD-3 secretion level increased significantly in the CHD (15.65 ± 2.68 pg/μg) and the AMN (14.94 ± 1.85 pg/μg) only when both regions were stimulated simultaneously.

CONCLUSION

The stimulation of human fetal membranes with S. agalactiae induced a differential and tissue-specific profile of HBD-1, HBD-2, and HBD-3 secretion.

Tissue-specific human beta-defensins (HBD)1, HBD2, and HBD3 secretion from human extra-placental membranes stimulated with Escherichia coli

BACKGROUND

During an ascending infection along the reproductive tract, the extra-placental membranes must act as a selective and competent barrier against pathogens. Human beta defensins (HBD)1, HBD2, and HBD3 are key elements of innate immunity that are secreted to neutralize/control the progression of infection.

METHODS

Full-thickness membranes were mounted on a Transwell device, constituted by two independent chambers, 1 × 10(6) CFU/ml of Escherichia coli were added to either the amnion (AMN) or the choriodecidual (CHD) face or to both. Secretion profiles of HBD1, HBD2, and HBD3 to the culture medium were quantified by ELISA.

RESULTS

In comparison with basal conditions, the secretion profile of HBD1 remained without significant changes; HBD2 level in CHD and AMN increased 1.9- and 1.4-times, respectively, after stimulation with bacteria. HBD3 secretion level increased significantly (7.8 +/- 1.9 pg/micrograms) in the CHD but only if the stimulus was applied on the AMN side.

CONCLUSIONS

Selective stimulation of extra-placental membranes with E. coli, results in a tissue specific secretion of HBD1, HBD2, and HBD3 mainly in the CHD, which is the first infected region during an ascending infection.

Temporal changes in circulating levels of plasma interleukin-8 during peripartum period in Murrah buffaloes (Bubalus bubalis) under subtropical climate

The objective of this study was to elucidate the changes in circulating levels of plasma interleukin-8 (IL-8) during peripartum period in Murrah buffaloes (Bubalus bubalis). IL-8 was estimated in blood plasma of healthy peripartum Murrah buffaloes (n=6) on days ± 30, ± 15, ± 5, ± 3, ± 1 and 0 pre- and postpartum with respect to the day of parturition (day 0) in each of the two different seasons (hot-humid and spring). The mean microclimate Temperature-Humidity Index (THI) during spring season was significantly lower (p<0.01) than the corresponding THI in hot-humid season. In both the seasons, plasma IL-8 remained lower in prepartum period (≤ 46.56 ± 14.08 pg/ml during spring and ≤ 73.18 ± 18.56 pg/ml during hot-humid season) than in the postpartum period (≥ 51.41 ± 13.82 pg/ml during spring and ≥ 84.13 ± 16.97 pg/ml in hot humid season). During spring, the IL-8 levels were significantly higher (P<0.05) on days+5 and +15 postpartum in comparison to the IL-8 levels on days -30, -5, and -3 prepartum. During hot-humid season, IL-8 level was significantly higher (P<0.05) on day +30 as compared to the IL-8 levels on days -30 and -5 prepartum. The correlation between IL-8 and mean microclimate THI was significant (r=0.25, P<0.01). From the results, it is concluded that peripartum period in buffaloes is associated with an inflammatory response leading to significantly higher plasma IL-8 during parturition and postpartum period than in the pre-partum period.

Comparison of LPS-stimulated release of cytokines in punch versus transwell tissue culture systems of human gestational membranes

BACKGROUND

Cytokine signaling within the amnionic, chorionic and decidual extraplacental gestational membranes plays an important role in membrane rupture and the timing of birth. The predominant in vitro explant culture system for evaluating cytokine induction in human gestational membranes has been the free-floating biopsy punch culture. Punch systems have been used to investigate the impact of various toxicants, pharmaceuticals and genetic variation on expression of pro-inflammatory cytokines. More recently, a dual compartment transwell culture system has been developed that more closely mimics the intrauterine compartment. The current study compares these two systems with respect to release of pro- and anti-inflammatory cytokines in response to lipopolysaccharide (LPS), a model stimulant.

METHODS

Tissue samples were exposed to 100 ng/ml LPS for 12 h and cytokines were measured by ELISA. Data are expressed as increase relative to non-treated controls.

RESULTS

Levels of interleukin-6 increased in punch culture medium samples to a significantly greater extent (34.2 fold) compared with medium from transwell cultures in the amnion (6.6 fold) or choriodecidual (7.1 fold) compartments. Interleukin-8 also showed a significantly greater induction in punch (4.8 fold) than transwell amnion (1.6 fold) or choriodecidual (1.7 fold) samples. The anti-inflammatory interleukin-10 showed a significant difference between punch (36.5 fold) and transwell amnion (15.4 fold) samples, but no difference was observed between punch and transwell choriodecidual (28.5 fold) samples. Neither interleukin-1beta nor tumor necrosis factor-alpha (TNF-alpha) showed a significant difference between the punch and transwell samples.

CONCLUSIONS

These results indicate that the pattern of LPS-stimulated cytokine release from gestational membranes in vitro depends on the culture system used, confounding comparisons of studies that use different gestational membrane culture systems to study inflammatory responses.

Tissue-specific induction of COX-2 and prostaglandins in lipopolysaccharide-stimulated extraplacental human gestational membranes in a 2-chamber transwell culture system

The current study investigates tissue-specific prostaglandin secretion and cyclooxygenase 2 (COX-2) induction in full-thickness human gestational membranes. Gestational membranes were collected from healthy, nonlaboring cesarean deliveries at 37 to 39 weeks gestation and cultured in 2-chamber Transwell devices. Lipopolysaccharide exposure (100 ng/mL for 8 hours) elevated prostaglandin E(2) and F(2α) concentrations in the amniotic chamber medium regardless of whether exposure was to the amniotic, decidual, or both sides of the membranes. However, prostaglandin E(2) and F(2 α) concentrations in the decidual chamber medium were elevated compared with controls only if the decidual side was exposed directly to lipopolysaccharide. Whereas prostaglandin F(2α) concentrations increased to similar extents in the amniotic and decidual chambers regardless of lipopolysaccharide exposure modality, prostaglandin E(2) concentrations were 22-fold higher on the amniotic side than the decidual side after lipopolysaccharide stimulation of the amnion. These findings demonstrate the propagation of prostaglandins, prostaglandin precursors, or other factors in the direction of the decidua to the amnion, but the reverse situation was not evident. Immunostaining for COX-2 was related to the side of lipopolysaccharide exposure, that is, exposure to the amnion caused immunostaining in cells of the collagen layers of the amnion and chorion, whereas exposure to the decidual side caused staining in decidual cells. These findings suggest that the inflammatory effect of lipopolysaccharide on COX-2 induction occurs within a localized area of exposure and that prostaglandins or their precursors move across the tissues of the gestational membranes by currently undefined transport mechanisms.