Microvesicles and exosomes released by amnion epithelial cells under oxidative stress cause inflammatory changes in uterine cells†

Abstract

Extracellular vesicles (EVs) play a crucial role in feto-maternal communication and provide an important paracrine signaling mechanism in pregnancy. We hypothesize that fetal cells-derived exosomes and microvesicles (MVs) under oxidative stress carry unique cargo and traffic through feto-maternal interface, which cause inflammation in uterine cells associated with parturition. Exosomes and MVs, from primary amnion epithelial cell (AEC) culture media under normal or oxidative stress (OS)-induced conditions, were isolated by optimized differential centrifugation method followed by characterization for size (nanoparticle tracking analyzer), shape (transmission electron microscopy), and protein markers (western blot and immunofluorescence). Cargo and canonical pathways were identified by mass spectroscopy and Ingenuity Pathway Analysis. Myometrial, decidual, and cervical cells were treated with 1x107 control/OS-derived exosomes/MVs. Pro-inflammatory cytokines were measured using a Luminex assay. Statistical significance was determined by paired T-test (p < 0.05). AEC produced cup-shaped exosomes of 90–150 nm and circular MVs of 160–400 nm. CD9, HSP-70, and Nanog were detected in exosomes while OCT-4, HLA-G, and calnexin were found in MVs. MVs, but not exosomes, were stained for phosphatidylserine. The protein profiles for control versus OS-derived exosomes and MVs were significantly different. Several inflammatory pathways related to OS were upregulated that were distinct between exosomes and MVs. Both OS-derived exosomes and MVs significantly increased pro-inflammatory cytokines (GMCSF, IL-6, and IL-8) in maternal cells compared to control (p < 0.05). Our findings suggest that fetal-derived exosomes and MVs under OS exhibited distinct characteristics and a synergistic inflammatory role in uterine cells associated with the initiation of parturition.

Histocompatibility Antigen, Class I, G (HLA-G)’s Role during Pregnancy and Parturition: A Systematic Review of the Literature

“…HLA-G predominantly induces its functions through receptor–ligand interactions; however, sHLA-G and HLA-G can also be packaged into exosomes and induce endocrine signaling [ 80 ]. As it has previously been shown that exosomes play a major role in the induction of labor at term and preterm [ 82 , 83 , 84 , 85 , 86 ], further characterization of exosomes from different intrauterine tissues is needed to elucidate their role in maintaining maternal–fetal immune homeostasis.…”

Fetal Membranes Contribute to Drug Transport across the Feto-Maternal Interface Utilizing the Breast Cancer Resistance Protein (BCRP)

“…The size distribution and concentration of exosomes were determined using Ze-taView™ PMX 110 (Particle Metrix, Meerbusch, Germany) and its corresponding software (ZetaView 8.02.28) as previously described by our lab [22,29,30]. Briefly, the frozen exosomes were thawed on ice and diluted in 1:1000 filtered distilled water.…”

“…Exosomes carry important cargo between their cells of origin and target cells. Multiple studies performed in our laboratory have demonstrated the potential functional role of exosomes derived from FM cells [20][21][22]. Exosomes derived from the AEC layer have been shown to carry important cargo that reflect the status of the cell in an oxidative stress environment [21].…”

“…Exosomes derived from the AEC layer have been shown to carry important cargo that reflect the status of the cell in an oxidative stress environment [21]. In addition, AEC-derived exosomes have led to an increased inflammatory response in maternal uterine cells, which could potentially play an important role in parturition [20,22]. We hypothesize that FM cells express BCRP and exosomes derived from FM cells contain the BCRP transport protein and potentially play a role in drug transportation across the feto-maternal interface.…”

Extracellular Vesicles as Natural Delivery Carriers Regulate Oxidative Stress Under Pathological Conditions

“…In addition, EVs have an important role in feto-maternal communication. Under oxidative stress, fetal cells-derived EVs can deliver unique cargos to parturition-associated uterine cells, inducing inflammation ( Shahin et al, 2021 ). The effects of oxidative stress-miseducated EVs on the immune system need to be taken seriously since the immune system involves in nearly all pathological diseases.…”