The New Old CD8+ T Cells in the Immune Paradox of Pregnancy

CD8+ T cells are the most frequent T cell population in the immune cell compartment at the feto-maternal interface. Due to their cytotoxic potential, the presence of CD8+ T cells in the immune privileged pregnant uterus has raised considerable interest. Here, we review our current understanding of CD8+ T cell biology in the uterus of pregnant women and discuss this knowledge in relation to a recently published immune cell Atlas of human decidua. We describe how the expansion of CD8+ T cells with an effector memory phenotype often presenting markers of exhaustion is critical for a successful pregnancy, and host defense towards pathogens. Moreover, we review new evidence on the presence of long-lasting immunological memory to former pregnancies and discuss its impact on prospective pregnancy outcomes. The formation of fetal-specific memory CD8+ T cell subests in the uterus, in particular of tissue resident, and stem cell memory cells requires further investigation, but promises interesting results to come. Advancing the knowledge of CD8+ T cell biology in the pregnant uterus will be pivotal for understanding not only tissue-specific immune tolerance but also the etiology of complications during pregnancy, thus enabling preventive or therapeutic interventions in the future.

Spatiotemporal Protein Expression Profiles of QSOX1 in the Murine Uterus, Placenta, and Embryo during Pregnancy

Quiescin Q6 sulfhydryl oxidase 1 (QSOX1) catalyzes the oxidation of the sulfhydryl group to disulfide bond and is widely expressed in various tissues. This study focuses on investigating QSOX1′s spatiotemporal and cellular protein expression profile of the pregnant uterus, placenta, and developing embryo during mouse pregnancy. Immunohistochemical staining was used to reveal the localization of QSOX1 protein, and HistoQuest was applied to quantify protein levels. The expression level of QSOX1 in the decidua and muscle cells of the pregnant uterus fluctuated dramatically during pregnancy. QSOX1 was ubiquitously expressed in the labyrinth, junction zone, and chorionic plate in the placenta. The quantitative analysis found that this protein was highly expressed in the spinal cord, lens, midbrain, cerebellum, medulla oblongata, and tooth of mouse embryos, followed by the heart, intercostal muscle, diaphragm, intermediate zone, extrinsic ocular muscle, spine, pons, epidermis, tongue, ganglion, vomeronasal organ, thoracic vertebrae, and thymus. Interestingly, QSOX1 was also markedly expressed in olfactory system tissues. This comprehensive spatiotemporal study of QSOX1 protein expression will provide a basis for further investigations of the QSOX1 physiological function in the pregnant uterus, placenta, and developing embryo.

Roles of Two Small Leucine-Rich Proteoglycans Decorin and Biglycan in Pregnancy and Pregnancy-Associated Diseases

Two small leucine-rich proteoglycans (SLRP), decorin and biglycan, play important roles in structural–functional integrity of the placenta and fetal membranes, and their alterations can result in several pregnancy-associated diseases. In this review, we briefly discuss normal placental structure and functions, define and classify SLRPs, and then focus on two SLRPs, decorin (DCN) and biglycan (BGN). We discuss the consequences of deletions/mutations of DCN and BGN. We then summarize DCN and BGN expression in the pregnant uterus, myometrium, decidua, placenta, and fetal membranes. Actions of these SLRPs as ligands are then discussed in the context of multiple binding partners in the extracellular matrix and cell surface (receptors), as well as their alterations in pathological pregnancies, such as preeclampsia, fetal growth restriction, and preterm premature rupture of membranes. Lastly, we raise some unanswered questions as food for thought.

The content of microbes in the cavity of the pregnant uterus Albert (Arch. f. G., Bd. 125, H. 3)

The content of microbes in the cavity of the pregnant uterus could have been detected by Albert (Arch. F. G., Bd. 125, H. 3) during an abortion by a small Caesar section. The author believes that the vagina always contains microbes that can infect the cervix and the uterine cavity at any time; in some cases, this infection, after a short and mild acute period, can go into a latent state, during which pregnancy is possible.

Identification of a novel distension-evoked motility pattern in the mouse uterus

The dynamic changes in uterine contractility in response to distension are incompletely understood. Rhythmic, propagating contractions of non-pregnant uterine smooth muscle occur in the absence of nerve activity (i.e. myogenic); events that decline during pregnancy and re-emerge at parturition. We therefore sought to determine how myogenic contractions of the non-pregnant uterus are affected by distension, which might provide mechanistic clues underlying distension-associated uterine conditions such as preterm birth. Uteri isolated from nulliparous adult female mice in proestrus were video imaged to generate spatiotemporal maps, and myoelectrical activity simultaneously recorded using extracellular suction electrodes. Motility patterns were examined under basal conditions and following ramped intraluminal distension with fluid to 5 and 10 cmH2O. Intraluminal distension caused pressure-dependent changes in the frequency, amplitude, propagation speed and directionality of uterine contractions, which reversed upon pressure release. Altered burst durations of underlying smooth muscle myoelectric events were concurrently observed, although action potential spike intervals were unchanged. Voltage-gated sodium channel blockade (TTX; 0.6 µM) attenuated both the amplitude of contractions and burst duration of action potentials, whereas all activity was abolished by L-type calcium channel blockade (nifedipine; 1 µM). These data suggest that myogenic motility patterns of the non-pregnant mouse uterus are sensitive to changes in intraluminal pressure and, at high pressures, may be modulated by voltage-gated sodium channel activity. Future studies may investigate whether similar distension-evoked changes occur in the pregnant uterus and the possible pathophysiological role of such activity in the development of preterm birth.

Uterine torsion of term pregnant uterus due to anterior fibroid

We present a case of uterine torsion caused by a large 7.0x8.0 cm subserosal myoma in a gravid uterus. This is an uncommon disorder where the prospective diagnosis is difficult thus raises challenges in management.Uterine torsion in gravid uterus is found to carry a substantial degree of risk of perinatal mortality. Leiomyoma is found to be a potential risk factor in these cases. Therefore the diagnosis must not be delayed to prevent complications. Though there are no imaging criteria, CT or MRI can produce a preoperative diagnosis. Uterine torsion can be asymptomatic and in most cases is an accidental finding during cesarian section. Thereby many times cesarian section yields the most certain diagnosis. Posterior low transverse incision is an accessible and effective approach in uterine torsion cases. High degree of suspicion along with swift management is essential factors contributing to favorable outcome.

Unicornuate uterus: case reports of heterogenous presentations challenging clinical diagnosis and management

Unicornuate uterus is an anomaly arising from defective lateral fusion of incompletely developed mullerian duct or paramesonephric duct with the contralateral duct. Pregnancy in non-communicating rudimentary horn can result in I and II trimester pregnancy losses along with maternal morbidity and mortality. Here we describe three such cases of unicornuate uterus with non-communicating rudimentary horn pregnancy, who presented to our hospital with pain in lower abdomen. Two of them with II trimester pregnancy landed in haemorrhagic shock owing to rupture of pregnant horn, though were revived by immediate intervention. Third patient who came with a definitive diagnosis of I trimester rudimentary horn pregnancy was managed electively by hemi-hysterectomy. Rupture of pregnant uterus can occur in II trimester when associated with uterine anomaly. Early sonographic diagnosis has a major offering in workup, management and prevention of mother from grave life threatening consequences.

Does Bacteria Colonization of Canine Newborns Start in the Uterus?

The assumption that requires the uterus to be a sterile environment to sustain a successful pregnancy has been recently challenged in humans, and is still under debate. The aim of this study was to assess whether bacteria can be isolated from the pregnant uterus and from amniotic fluid and meconium of healthy canine fetuses at term, delivered through cesarean section. Fifteen dams of different breed, age and parity, undergoing either elective (n = 10) or emergency (n = 5) cesarean section after a healthy pregnancy, were included in the study. Swabs for bacterial culture were collected from the uterus, and from amniotic fluid and meconium. Bacteria were isolated from all the sampled sites and materials, irrespective of cesarean type. In most cases, different bacteria were isolated from the different sites. Acinetobacter spp., coagulase-negative Staphylococci and Bacillus spp. were frequently found while Pseudomonas aeruginosa, Micrococcus spp., Moraxella spp., Macrococcus spp., Glutamicibacter spp., Stenotrophomonas spp. and Psychrobacter spp. were only occasionally identified. Our data show that uterus and fetuses may not be sterile in healthy term canine pregnancies.

Ovarian cyst elevation using a metreurynter for laparoscopic cystectomy of a benign ovarian cyst during pregnancy

Background A uterine manipulator cannot be used to elevate the ovary in benign ovarian surgery during pregnancy. This report describes our method of elevation of the ovary using a metreurynter with the success rate of the procedure and a comparison of surgical results and pregnancy outcomes between the successful and unsuccessful cases. Methods Between August 2003 and February 2020, 11 pregnant patients with a tumor found sunk in the Cul-de-sac underwent laparoscopic cystectomy for a benign ovarian cyst with a metreurynter. The surgical results, success and failure of the elevation by a metreurynter, pregnancy outcomes, and fetal status at delivery were evaluated. Results Elevation of ovarian tumors with a metreurynter was successful in nine cases. However, it was unsuccessful in the remaining two cases wherein the ovary was lifted with forceps while the uterus was in a compressed state. The operative time was also longer in these cases. The pregnancy prognosis, however, was good for both, successful and unsuccessful cases. Conclusions The metreurynter is an inexpensive and practical obstetric device, and its optimal use allows the performance of a procedure with minimal burden on a pregnant uterus. Therefore, we recommend the appropriate use of this method to enable effective laparoscopic cystectomy of ovarian tumors during pregnancy.