Search Results (7)

Vitamin D is a pleiotropic secosteroid with endocrine and intracrine actions that influence key phases of allogeneic hematopoietic stem cell transplantation. Epithelial barriers, antigen-presenting cells and effector lymphocytes express the vitamin D receptor and enzymes required for local activation, allowing circulating 25-hydroxyvitamin D to be converted into its active form and modulate immune interactions. During the peri-transplant period, sunlight deprivation, reduced intake, mucosal injury, cholestasis and corticosteroid exposure markedly reduce vitamin D levels at a time when antigen presentation and immune reconstitution occur. This review integrates mechanistic immunology with clinical observations and interventional data to outline strategies that prevent severe deficiency. It summarizes epidemiology before and after transplantation, associations with acute and chronic graft-versus-host disease, relapse, engraftment, infections, bone health and survival, and evaluates dosing approaches including pre-conditioning loading and reassessment at day thirty with escalation if needed. Absorption-savvy formulations such as oral thin-film and intramuscular cholecalciferol are considered when gastrointestinal function is compromised. Given the high prevalence of deficiency, biological plausibility, safety and low cost, a structured approach that includes screening, repletion and monitoring to achieve concentrations of at least thirty nanograms per milliliter by day thirty represents a pragmatic and low-risk component of supportive care pending definitive evidence. Full article

Urethral stricture is a disease of fibrotic narrowing that compromises the urethral mucosa and spongiosum. Oral mucosal graft urethroplasty delivers excellent outcomes in complex cases, yet its procedural demands restrict availability beyond specialized centers. Endoscopic transplantation of oral mucosa has been proposed; while feasibility is shown, clinical efficacy remains suboptimal. We asked whether extracellular vesicles from stem cells of human exfoliated deciduous teeth (SHED-EVs) promote oral mucosa fibroblast (OMF) growth under urethra-mimetic paracrine conditions and whether culture growth phase tunes EV function. SHED-EVs were collected during logarithmic (SHED-EV-L) or stationary (SHED-EV-S) phases under xeno-free conditions, isolated by a standardized workflow, and characterized by nanoparticle tracking analysis. miRNA cargo was profiled with a human miRNA microarray platform and normalized for comparative analyses. OMF proliferation was quantified in a horizontal indirect co-culture with urethral epithelial cells using incubator-based time-lapse imaging. SHED-EV-L produced a sustained pro-proliferative effect across 24–96 h, whereas SHED-EV-S showed a weaker early effect with a late catch-up; both exceeded vehicle at 96 h. Fibrosis-related miRNA heat maps showed culture growth phase-dependent patterns: SHED-EV-L displayed relatively higher signals for miR-31-3p, miR-146b-3p, several let-7 members, and selected miR-181 isoforms, whereas SHED-EV-S showed a marked relative increase of miR-486-3p; miR-21, miR-99/100, and miR-205 were broadly comparable between phases. These findings indicate that culture growth phase is a practical design lever that orients SHED-EV cargo and function, supporting phase-matched formulations for adjunctive transurethral applications and motivating in vivo validation and manufacturing-oriented quality controls. Full article

Urethral stricture involves fibrotic narrowing of the urethral mucosa and spongiosum. Although urethroplasty using oral mucosal grafts is the gold standard for complex cases due to its high success rate, technical complexity limits its broader adoption. To address this, endoscopic transplantation of oral mucosal tissue has been proposed. While feasibility has been demonstrated, clinical efficacy remains suboptimal. Developing adjunctive factors that facilitate mucosal engraftment may improve outcomes of endoscopic transplantation. Extracellular vesicles (EVs)—membrane-bound nanoparticles secreted by cells that deliver miRNAs and other bioactive molecules—have recently emerged as promising candidates. We investigated EVs derived from four mesenchymal stromal cell (MSC) sources—stem cells from human exfoliated deciduous teeth (SHED), adipose tissue, umbilical cord, and bone marrow (BM)—isolated during both logarithmic (log) and stationary culture phases. miRNA profiling revealed distinct phase- and origin-specific signatures. SHED-derived EVs from the log phase and bone marrow-derived EVs from the stationary phase expressed miR-31, the let-7 family, and miR-205, suggesting early wound healing potential. In contrast, stationary-phase SHED-EVs and log-phase BM-MSC-EVs were enriched in the miR-99 family and miR-31, indicating potential roles in epithelial stabilization and fibrosis modulation. These findings support phase-specific application of MSC-EVs to optimize mucosal engraftment in transurethral reconstruction. Full article

Mucositis involving the gastrointestinal, vaginal, and nasal mucosa is one of the primary dose-limiting toxicities of hematopoietic stem cell transplantation (HSCT) and its conditioning regimen. The oropharyngeal mucosa is commonly affected, which can be detrimental to patient health and quality of life. Despite its significant prevalence and deleterious effects, we have an inadequate understanding of the risk factors and outcomes associated with oral mucositis (OM). We performed a literature search through PubMed and EBSCO (inception to 31 March 2024) following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data was extracted from eligible studies using a pre-specified data extraction form. Quality of the data was assessed using the Newcastle-Ottawa Scale for non-randomized, observational studies and the Cochrane Collaboration Tool for randomized controlled trials. Our initial search identified 1677 articles, 34 of which were included in our study. Of those 34, 30 were included in the qualitative assessment of clinical risk factors in the development of OM, and 4 were included in the meta-analysis assessing the relationship between OM and infectious complications following HSCT. Across both HSCT modalities and cancer cohorts, female sex and high-intensity conditioning were common risk factors in the development of OM. When stratified by allogeneic and autologous HSCT, methotrexate, younger age, and longer duration of neutropenia were associated with increased OM risk in allogeneic HSCT recipients, while renal dysfunction, HSV-1 reactivation, and longer neutrophil engraftment were associated with increased OM risk in autologous HSCT recipients. Longer neutrophil engraftment was a common risk factor across different cancer cohorts; however, renal dysfunction was a distinct risk factor for OM in multiple myeloma patients. Additionally, our meta-analysis revealed that patients with OM have an increased risk of developing infectious complications following HSCT compared to those without OM, with an odds ratio of 3.84 (95% CI: 2.51–5.86). The development of OM is related to various risk factors, and individuals with OM are at greater risk of infectious complications. Knowledge of these risk factors and outcomes will help clinicians identify high-risk individuals, prevent OM, and protect an immunocompromised population from subsequent life-threatening complications. Full article

Nutritional status is an important prognostic factor in patients with multiple myeloma (MM). The Controlling Nutritional Status (CONUT) score has shown promise in predicting outcomes in various malignancies; however, its role in autologous stem cell transplantation (ASCT) in patients with MM remains unclear. This study aimed to evaluate the significance of pre-transplant CONUT scores in predicting post-transplant engraftment kinetics and early complications in patients with MM undergoing ASCT. This single-center, retrospective study analyzed 59 multiple myeloma patients who underwent ASCT between 1 October 2022, and 1 July 2024. Pre-transplant CONUT scores were calculated, and their associations with various post-transplant outcomes were assessed using statistical analyses. Higher CONUT scores were independently associated with longer neutrophil engraftment times (p = 0.012). Patients who developed oral mucositis (OM) had significantly higher CONUT scores than those without OM (p = 0.028). A CONUT score cut-off of 2.5 demonstrated 100% sensitivity and 57.14% specificity in predicting OM (Area Under the Curve (AUC) 0.792, 95% CI: 0.654–0.930, p = 0.033). Our study demonstrates that a higher pre-transplant CONUT score is significantly associated with a delay in neutrophil engraftment and an increased risk of developing oral mucositis. These findings suggest that the CONUT score can serve as a valuable predictive tool for early post-transplant complications, thereby guiding targeted interventions and improving patient management. Full article

The first product in the world for ex vivo cultivated oral mucosal epithelial cell transplantation (COMET) to treat limbal stem cell deficiency (LSCD), named Ocural^®, was launched in June 2021 in Japan. COMET was performed on two patients, including the first case in the post-marketing phase of Ocural^®. Pathological and immunohistochemical examinations were also carried out using specimens obtained before and after COMET and the spare cell sheet. In case 1, the ocular surface remained free from epithelial defects for approximately six months. In case 2, although defect of the cornea-like epithelia was observed after COMET for one month, it was resolved after the insertion of lacrimal punctal plugs. In case 1, adjuvant treatment was interrupted due to an accident during the second month after COMET, resulting in conjunctival ingrowth and corneal opacity. Eventually, a lamellar keratoplasty was required at six months after COMET. Immunohistochemistry revealed the presence of markers for stem cells (p63, p75), proliferation (Ki-67), and differentiation (Keratin-3, -4, and -13) in both the cornea-like tissue after COMET and a cultivated oral mucosal epithelial cell sheet. In conclusion, Ocural^® can be accomplished without major complications, and the stem cells derived from oral mucosa might be successfully engrafted. Full article

IgA-coated bacteria in the gut (IgA-biome) provide a homeostatic function in healthy people through inhibition of microbial invaders and by protecting the epithelial monolayer of the gut. The laboratory methods used to detect this group of bacteria require flow cytometry and DNA sequencing (IgA-Seq). With dysbiosis (reduced diversity of the microbiome), the IgA-biome also is impaired. In the presence of enteric infection, oral vaccines, or an intestinal inflammatory disorder, the IgA-biome focuses on the pathogenic bacteria or foreign antigens, while in other chronic diseases associated with dysbiosis, the IgA-biome is reduced in capacity. Fecal microbiota transplantation (FMT), the use of fecal product from well-screened, healthy donors administered to patients with dysbiosis, has been successful in engrafting the intestine with healthy microbiota and metabolites leading to improve health. Through FMT, IgA-coated bacteria have been transferred to recipients retaining their immune coating. The IgA-biome should be evaluated in FMT studies as these mucosal-associated bacteria are more likely to be associated with successful transplantation than free luminal organisms. Studies of the microbiome pre- and post-FMT should employ metagenomic methods that identify bacteria at least at the species level to better identify organisms of interest while allowing comparisons of microbiota data between studies. Full article