Fetal surgery for myelomeningocele is effective: a critical look at the whys

Formerly, the disastrous cluster of neurologic deficits and associated neurogenic problems in patients with myelomeningocele (MMC) was generally thought to solely result from the primary malformation, i.e., failure of neurulation. Today, however, there is no doubt that a dimensional additional pathogenic mechanism exists. Most likely, it contributes much more to loss of neurologic function than non-neurulation does. Today, there is a large body of compelling experimental and clinical evidence confirming that the exposed part of the non-neurulated spinal cord is progressively destroyed during gestation, particularly so in the third trimester. These considerations gave rise to the two-hit-pathogenesis of MMC with non-neurulation being the first and consecutive in utero acquired neural tissue destruction being the second hit. This novel pathophysiologic understanding has obviously triggered the question whether the serious and irreversible functional loss caused by the second hit could not be prevented or, at least, significantly alleviated by timely protecting the exposed spinal cord segments, i.e., by early in utero repair of the MMC lesion. Based on this intriguing hypothesis and the above-mentioned data, human fetal surgery for MMC was born in the late nineties of the last century and has made its way to become a novel standard of care, particularly after the so-called "MOMS Trial”. This trial, published in the New England Journal of Medicine, has indisputably shown that overall, open prenatal repair is distinctly better than postnatal care alone. Finally, a number of important other topics deserve being mentioned, including the necessity to work on the up till now immature endoscopic fetal repair technique and the need for concentration of these extremely challenging cases to a small number of really qualified fetal surgery centers worldwide. In conclusion, despite the fact that in utero repair of MMC is not a complete cure and not free of risk for both mother and fetus, current data clearly demonstrate that open fetal-maternal surgery is to be recommended as novel standard of care when pregnancy is to be continued and when respective criteria for the intervention before birth are met. Undoubtedly, it is imperative to inform expecting mothers about the option of prenatal surgery once their fetus is diagnosed with open spina bifida

Subsequent Pregnancy Outcomes after Open in utero Spina Bifida Repair

INTRODUCTION: Fetal spina bifida (SB) repair is a distinct therapeutic option in selected cases. Since this procedure may not only be associated with short-term obstetrical complications, the aim of this study was to assess the outcomes of subsequent pregnancies after open fetal SB repair. METHODS: 138 patients having had open fetal SB repair at our center received a questionnaire regarding the occurrence, course, and outcome of subsequent pregnancies. Additionally, medical records were reviewed. All subsequent pregnancies with complete outcome data that progressed beyond 20 gestational weeks (GW) were included for further analysis. RESULTS: 70% of all women answered the questionnaire. Out of this cohort, 35 subsequent pregnancies were reported in 29% of women. The rate of early pregnancy loss including elective terminations was 14%. All 29 pregnancies processing >20 GW ended in live births without preterm births <34th GW. Mean gestational age at delivery was 37.3 ± 1.4 GW. Uterine rupture occurred in two cases (7%) and uterine thinning/dehiscence was present in six cases (21%). No maternal transfusions were required. CONCLUSION: When counseling women undergoing open fetal SB repair, one should consider possible risks for subsequent pregnancies, especially the one of uterine dehiscence and rupture that is similar compared to numbers reported after classical cesarean deliveries

Prenatal Spina Bifida Repair: Defendable Trespassing of MOMS Criteria Results in Commendable Personalized Medicine

Introduction We hypothesize that after publication of the quintessence of the MOMS-Trial, eligibility criteria for prenatal spina bifida repair may be modified if a tenable argumentation underlies this decision. Methods Our first 154 fetal surgery patients were analyzed with particular focus on how many, which, and why the original eligibility criteria, set forth by the MOMS Trial Protocol, were disobeyed, and what the eventually detectable, negative and positive, impact of these deviations on outcomes was. Results A total of 152 patients (2 missing consent) were included (100%). In 69 patients (45.4%), a total of 89 eligibility criteria were disobeyed. In 54 (35.6%) cases, maternal criteria were concerned: Gestational age at operation of >25+6 weeks in 17 (11.2%), uterine pathologies in 13 (8.6%) women, preoperative BMI≥35 kg/m2 in 12 (7.9%), previous hysterotomy in 7 (4.6,%), previous prematurity in 3 (2%), HIV/hepatitis B in 2 (1.3%), psychosocial issues in 2 (1.3%), and placenta praevia in 1 (0.7%). In 32 (21.1%) cases, fetal criteria were disobeyed: Fetal anomaly unrelated to spina bifida in 19 (12.5%), no/minimal evidence of hindbrain herniation in 13 (8.6%), and severe kyphosis in 2 (1.3%). We could not identify cases where non-observation of criteria led to clear-cut maternal and/or fetal disadvantages. Conclusion This study shows that MOMS-Trial eligibility criteria for prenatal spina bifida repair should be modified or even abandoned with adequate medical and ethical argumentation, and with written parental informed consent after non-directive, full disclosure counseling. This clear cut change of paradigm is a necessity as it leads towards personalized medicine allowing more fetuses to benefit from fetal surgery than would have benefitted with the former published MOMS criteria in place

Effects of an Adipose Mesenchymal Stem Cell-Derived Conditioned medium and TGF-β1 on Human Keratinocytes In Vitro

Human keratinocytes play a crucial role during skin wound healing and in skin replacement therapies. The secretome of adipose-derived stem cells (ASCs) has been shown to secrete pro-healing factors, among which include TGF-β1, which is essential for keratinocyte migration and the re-epithelialization of cutaneous wounds during skin wound healing. The benefits of an ASC conditioned medium (ASC-CM) are primarily orchestrated by trophic factors that mediate autocrine and paracrine effects in keratinocytes. Here, we evaluated the composition and the innate characteristics of the ASC secretome and its biological effects on keratinocyte maturation and wound healing in vitro. In particular, we detected high levels of different growth factors, such as HGF, FGFb, and VEGF, and other factors, such as TIMP1 and 4, IL8, PAI-1, uPA, and IGFBP-3, in the ASC-CM. Further, we investigated, using immunofluorescence and flow cytometry, the distinct effects of a human ASC-CM and/or synthetic TGF-β1 on human keratinocyte proliferation, migration, and cell apoptosis suppression. We demonstrated that the ASC-CM increased keratinocyte proliferation as compared to TGF-β1 treatment. Further, we found that the ASC-CM exerted cell cycle progression in keratinocytes via regulating the phases G1, S, and G2/M. In particular, cells subjected to the ASC-CM demonstrated increased DNA synthesis (S phase) compared to the TGF-β1-treated KCs, which showed a pronounced G0/G1 phase. Furthermore, both the ASC-CM and TGF-β1 conditions resulted in a decreased expression of the late differentiation marker CK10 in human keratinocytes in vitro, whereas both treatments enhanced transglutaminase 3 and loricrin expression. Interestingly, the ASC-CM promoted significantly increased numbers of keratinocytes expressing epidermal basal keratinocyte markers, such DLL1 and Jagged2 Notch ligands, whereas those ligands were significantly decreased in TGF-β1-treated keratinocytes. In conclusion, our findings suggest that the ASC-CM is a potent stimulator of human keratinocyte proliferation in vitro, particularly supporting basal keratinocytes, which are crucial for a successful skin coverage after transplantation. In contrast, TGF-β1 treatment decreased keratinocyte proliferation and specifically increased the expression of differentiation markers in vitro

Sleep-disordered breathing on respiratory polygraphy in neonates with spina bifida

INTRODUCTION Studies have shown a high prevalence of sleep-disordered breathing (SDB) in children with spina bifida. International standards for regular testing for SDB in this population are lacking. While there are studies investigating the prevalence of SDB in children with spina bifida, there are close to no studies in neonates. AIM AND OBJECTIVE To evaluate if routine respiratory polygraphy (RPG) testing is indicated for neonates with spina bifida and if yes, with what therapeutic consequence. METHODS We conducted a retrospective cohort study of all neonates with spina bifida at the University (Children's) Hospital Zurich after fetal spina bifida repair born between 2017 and 2022, who had undergone at least 1 RPG evaluation during hospitalization on the neonatal ward. RPG were evaluated by a blinded group of experienced pediatric pulmonologists. Based on the neonatal RPG results and pediatric pulmonologist's recommendation for caffeine therapy the spina bifida cohort was divided into two groups. Neonatal baseline RPG and follow-up RPG at the age of the 3 months were evaluated. RESULTS 48 neonates with RPG were included. Compared to the standard values in healthy neonates, the RPG results of this spina bifida cohort showed findings of SDB with central apnea and hypopnea. 22 (45.8%) neonatal RPG evaluations detected central SDB, prompting caffeine therapy. Follow-up RPG conducted after 3 months showed significant improvement of SDB with (almost) no need for continuation of caffeine. CONCLUSION We recommend the implementation of routine RPG testing in neonates with spina bifida to detect SDB and facilitate early targeted treatment

Are Cervical Length and Fibronectin Predictors of Preterm Birth after Fetal Spina Bifida Repair? A Single Center Cohort Study

BACKGROUND: A remaining risk of fetal spina bifida (fSB) repair is preterm delivery. This study assessed the value of preoperative cervical length (CL), CL dynamics (∆CL) and fetal fibronectin (fFN) tests to predict obstetric complications and length of stay (LOS) around fSB repair. METHODS: 134 patients were included in this study. All patients had CL measurement and fFN testing before fSB repair. ∆CL within the first 14 days after intervention and until discharge after fSB repair were compared in groups (∆CL ≥ 10 mm/&lt;10 mm; ≥20 mm/&lt;20 mm). CL before surgery, ∆CL's, and positive fFN tests were correlated to obstetric complications and LOS. RESULTS: Mean CL before surgery was 41 ± 7 mm. Mean GA at birth was 35.4 ± 2.2 weeks. In the group of ∆CL ≥ 10 mm within the first 14 days after intervention, LOS was significantly longer (p = 0.02). ∆CL ≥ 10 mm until discharge after fSB was associated with a significantly higher rate of GA at birth &lt;34 weeks (p = 0.03). The 3 positive fFN tests before fSB repair showed no correlation with GA at birth. CONCLUSION: Perioperative ∆CL influences LOS after fetal surgery. ∆CL ≥ 10 mm until discharge after fSB repair has a 3-times higher rate of preterm delivery before 34 weeks. Preoperative fFN testing showed no predictive value for preterm birth after fSB repair and was stopped

scRNA-Seq of Cultured Human Amniotic Fluid from Fetuses with Spina Bifida Reveals the Origin and Heterogeneity of the Cellular Content

Amniotic fluid has been proposed as an easily available source of cells for numerous applications in regenerative medicine and tissue engineering. The use of amniotic fluid cells in biomedical applications necessitates their unequivocal characterization; however, the exact cellular composition of amniotic fluid and the precise tissue origins of these cells remain largely unclear. Using cells cultured from the human amniotic fluid of fetuses with spina bifida aperta and of a healthy fetus, we performed single-cell RNA sequencing to characterize the tissue origin and marker expression of cultured amniotic fluid cells at the single-cell level. Our analysis revealed nine different cell types of stromal, epithelial and immune cell phenotypes, and from various fetal tissue origins, demonstrating the heterogeneity of the cultured amniotic fluid cell population at a single-cell resolution. It also identified cell types of neural origin in amniotic fluid from fetuses with spina bifida aperta. Our data provide a comprehensive list of markers for the characterization of the various progenitor and terminally differentiated cell types in cultured amniotic fluid. This study highlights the relevance of single-cell analysis approaches for the characterization of amniotic fluid cells in order to harness their full potential in biomedical research and clinical applications

CD146 expression profile in human skin and pre-vascularized dermo-epidermal skin substitutes in vivo

Background CD146 is a cell adhesion molecule whose expression profile in human skin has not yet been elucidated. Here, we characterize CD146 expression pattern in human skin, in particular in blood endothelial cells (BECs) and lymphatic endothelial cells (LECs), which constitute human dermal microvascular endothelial cells (HDMECs), as well as in perivascular cells. Results We demonstrated that CD146 is a specific marker of BECs, but not of LECs. Moreover, we found CD146 expression also in human pericytes surrounding blood capillaries in human skin. In addition, we demonstrated that CD146 expression is up-regulated by the TNFα-IL-1β/NF-kB axis in both BECs and pericytes. Finally, we engineered 3D collagen hydrogels composed of HDMECs, CD146+ pericytes, and fibroblasts which developed, in vitro and in vivo, a complete microvasculature network composed of blood and lymphatic capillaries with pericytes investing blood capillaries. Conclusions Overall, our results proved that CD146 is a specific marker of BECs and pericytes, but not LECs in human skin. Further, the combination of CD146+ pericytes with HDMECs in skin substitutes allowed to bioengineer a comprehensive 3D in vitro and in vivo model of the human dermal microvasculature

Immune cell populations and cytokine production in spleen and mesenteric lymph nodes after laparoscopic surgery versus conventional laparotomy in mice

Purpose: There is evidence that open as well as minimally invasive abdominal surgery impair post-operative innate and acquired immune function. To compare the impact of these approaches as well as the one of different peritoneal gas exposures on immune function, we investigated cellular as well as cytokine-based immune parameters in mesenteric lymph nodes and the spleen postoperatively. Methods: Mice (n=26) were randomly assigned to the 4 study groups: (1) sham controls undergoing anesthesia alone, (2) laparotomy, and (3) air, or (4) carbon dioxide pneumoperitoneum. Mice were sacrificed 48h after the intervention, and their spleens and mesenteric lymph nodes were harvested. Cytokine production (TNF-α, IL-6, IL-10, and IFN-γ), splenic T cell subpopulations (cytotoxic T cells, T helper cells, and regulatory T cells) were analyzed. Results: TNF-α production of splenocytes 16h after ex vivo lipopolysaccharides (LPS) stimulation was significantly increased in the laparotomy group compared to all other groups. In contrast, TNF-α production of lymph node cells and IL-6 production of splenocytes after ex vivo LPS stimulation did not differ significantly between the groups. The numbers of regulatory T cells (Treg) in the spleen differed between groups. A significant reduction in Treg cell frequency was detected in the CO2 insufflation group compared to the laparotomy and the air insufflation group. Conclusion: Our findings demonstrate a distinct difference in immune effector functions and cellular composition of the spleen with regard to splenic TNF-α production and increased numbers of Treg cells in the spleen. These findings are in line with a higher peritoneal inflammatory status consequent to peritoneal air rather than CO2 exposure. Treg turned out to be key modulators of postoperative dysfunction of acquired immunit

Bioengineering and in utero transplantation of fetal skin in the sheep model: A crucial step towards clinical application in human fetal spina bifida repair

An intricate problem during open human fetal surgery for spina bifida regards back skin closure, particularly in those cases where the skin defect is much too large for primary closure. We hypothesize that tissue engineering of fetal skin might provide an adequate autologous skin substitute for in utero application in such situations. Eight sheep fetuses of four time-mated ewes underwent fetoscopic skin biopsy at 65 days of gestation. Fibroblasts and keratinocytes isolated from the biopsy were used to create fetal dermo-epidermal skin substitutes. These were transplanted on the fetuses by open fetal surgery at 90 days of gestation on skin defects (excisional wounds) created during the same procedure. Pregnancy was allowed to continue until euthanasia at 120 days of gestation. The graft area was analyzed macroscopically and microscopically. The transplanted fetal dermo-epidermal skin substitutes was well discernable in situ in three of the four fetuses available for analysis. Histology confirmed healed grafts with a close to natural histological skin architecture four weeks after in utero transplantation. This experimental study generates evidence that laboratory grown autologous fetal skin analogues can successfully be transplanted in utero. These results have clinical implications as an analogous procedure might be applied in human fetuses undergoing prenatal repair to facilitate primary skin closure. Finally, this study may also fertilize the field of fetal tissue engineering in general, particularly when more interventional, minimally invasive, and open fetal surgical procedures become available