Fermín E. Gonzalez

Regenerative endodontics (RE) is a biologically based procedure designed to replace damaged dental structures, including dentin and root structures, and cells of the pulp-dentin complex. It is the first-line treatment for patients with immature permanent teeth (IPT) that have lost vitality due to dentoalveolar trauma (DAT), caries, or developmental anomalies such as dens evaginatus (DE). Beyond resolving clinical signs and symptoms, RE allows for continued root development, substantially improving the long-term prognosis of these cases. Here, we present a clinical case of a 12-year-old female patient who, as a result of dentoalveolar trauma, exhibits asymptomatic apical periodontitis of tooth 1.1 and chronic apical abscess of tooth 2.1 in IPT. Both teeth were treated with regenerative endodontics, achieving successful RE in tooth 2.1 and inducing apical closure with Biodentine in tooth 1.1. In addition, we conducted a bioinformatic analysis to identify key genes associated with the success of post-trauma RE, providing a more complete and mechanistic understanding of the factors determining treatment success. In conclusion, the success of RE procedures in IPT may be conditioned by the type of DAT suffered by the tooth. Moreover, incorporating bioinformatic analysis introduces an innovative approach to unravel the molecular mechanisms involved in post-trauma dental regeneration.

Tumor hypoxia, a hallmark of the tumor microenvironment (TME), profoundly impacts the antitumor functionality of immune cells, particularly natural killer (NK) cells, which play a critical role in cancer immunosurveillance and immunotherapy success. This review provides a comprehensive analysis of the mechanisms by which hypoxia impairs NK cell-mediated cytotoxicity and antitumor activities, emphasizing the molecular pathways and cellular adaptations that enable cancer cell to evade NK cell attack. Key factors that participate in this phenomenon include the stabilization of hypoxia-inducible factors, metabolic reprogramming, angiogenesis, cancer stemness, autophagy, and the secretion of immunosuppressive molecules. Moreover, hypoxia induces phenotypic and functional changes in both cancer and NK cells, promoting tumor progression and resistance to immunotherapy. Emerging strategies to counteract hypoxia-induced immunosuppression are being explored, including nanotechnology-based approaches, cytokine-mediated NK cell preconditioning, and vascular normalization techniques. These interventions highlight promising avenues for enhancing NK cell functionality and synergizing with existing cancer therapies. By addressing the immunosuppressive challenges of the hypoxic TME, in this review, we underscore the potential of innovative strategies to improve therapeutic outcomes in cancer treatment.

Ferroptosis is implicated in the pathogenesis of numerous chronic-inflammatory diseases, yet its association with progressive periodontitis remains unexplored. To investigate the involvement and significance of ferroptosis in periodontitis progression, we assessed sixteen periodontitis-diagnosed patients. Disease progression was clinically monitored over twelve weeks via weekly clinical evaluations and gingival crevicular fluid (GCF) collection was performed for further analyses. Clinical metrics, proteomic data, in silico methods, and bioinformatics tools were combined to identify protein profiles linked to periodontitis progression and to explore their potential connection with ferroptosis. Subsequent western blot analyses validated key findings. Finally, a single-cell RNA sequencing (scRNA-seq) dataset (GSE164241) for gingival tissues was analyzed to elucidate cellular dynamics during periodontitis progression. Periodontitis progression was identified as occurring at a faster rate than traditionally thought. GCF samples from progressing and non-progressing periodontal sites showed quantitative and qualitatively distinct proteomic profiles. In addition, specific biological processes and molecular functions during progressive periodontitis were revealed and a set of hub proteins, including SNCA, CA1, HBB, SLC4A1, and ANK1 was strongly associated with the clinical progression status of periodontitis. Moreover, we found specific proteins - drivers or suppressors - associated with ferroptosis (SNCA, FTH1, HSPB1, CD44, and GCLC), revealing the co-occurrence of this specific type of regulated cell death during the clinical progression of periodontitis. Additionally, the integration of quantitative proteomic data with scRNA-seq analysis suggested the susceptibility of fibroblasts to ferroptosis. Our analyses reveal proteins and processes linked to ferroptosis for the first time in periodontal patients, which offer new insights into the molecular mechanisms of progressive periodontal disease. These findings may lead to novel diagnostic and therapeutic strategies.

Cancer vaccines present a promising avenue for treating immune checkpoint blockers (ICBs)-refractory patients, fostering immune responses to modulate the tumor microenvironment. We revisit a phase I/II trial using Tumor Antigen-Presenting Cells (TAPCells) (NCT06152367), an autologous antigen-presenting cell vaccine loaded with heat-shocked allogeneic melanoma cell lysates. Initial findings showcased TAPCells inducing lysate-specific delayed-type hypersensitivity (DTH) reactions, correlating with prolonged survival. Here, we extend our analysis over 15 years, categorizing patients into short-term (pos patients exhibit a 53.1% three-year survival compared to 16.1% in DTH^neg patients. Extended remissions are observed in long-term survivors, particularly DTH^pos/M1c^neg patients. Younger age, stage III disease, and moderate immune events also benefit short-term survivors. Immunomarkers like increased C-type lectin domain family 2 member D on CD4⁺ T cells and elevated interleukin-17A were detected in long-term survivors. In contrast, toll-like receptor-4 D229G polymorphism and reduced CD32 on B cells are associated with reduced survival. TAPCells achieved stable long remissions in 35.2% of patients, especially M1c^neg/DTH^pos cases. Conclusions: Our study underscores the potential of vaccine-induced immune responses in melanoma, emphasizing the identification of emerging biological markers and clinical parameters for predicting long-term remission.

Despite the understanding of the coronavirus disease-19 (COVID-19), the role of salivary extracellular vesicles (sEVs) in COVID-19 remains unclear. Exploring the proteomic cargo of sEVs could prove valuable for diagnostic and prognostic purposes in assessing COVID-19. The proteomic cargo of sEVs from COVID-19(+) subjects and their healthy close contacts (HCC) was explored. sEVs were isolated by ultracentrifugation from unstimulated saliva samples, and subsequently characterized through nanoparticle tracking, transmission electron microscopy, and Western blot analyses. The proteomic cargo of sEVs was processed by LC-MS/MS. sEVs were morphologically compatible with EVs, with the presence of Syntenin-1 and CD81 EV markers. The sEV pellet showed 1417 proteins: 1288 in COVID-19(+) cases and 1382 in HCC. In total, 124 proteins were differentially expressed in sEVs from COVID-19(+) subjects. “Coronavirus-disease response”, “complement and coagulation cascades”, and “PMN extracellular trap formation” were the most enriched KEGG pathways in COVID-19(+) cases. The most represented biological processes were “Hemoglobin and haptoglobin binding” and “oxygen carrier activity”, and the best-denoted molecular functions were “regulated exocytosis and secretion” and “leucocyte and PMN mediated immunity”. sEV proteomic cargo in COVID-19(+) suggests activity related to immune response processes, oxygen transport, and antioxidant mechanisms. In contrast, in HCC, sEV signature profiles are mainly associated with epithelial homeostasis.

Background and Objective: There is no clear understanding of molecular events occurring in the periodontal microenvironment during clinical disease progression. Our aim was to explore qualitative and quantitative differences in gingival crevicular fluid (GCF) protein profiles from patients diagnosed with periodontitis between non‐progressive and progressive periodontal sites.Methods: Five systemically healthy patients diagnosed with periodontitis were monitored weekly in their progression of the disease and GCF samples from 10 candidate sites were obtained. Two groups of five sites, matched from an equal number of teeth, were selected from the five patients: Progression (PG) and Non‐Progression (NP). Global protein identification was performed with high‐throughput proteomic approaches and label‐free analysis determined their relative abundances. Proteins were identified by Proteome Discoverer v2.4 and searched against human SwissProt protein databases. Enrichment bioinformatic analyses were performed in STRING‐DB and ShinyGO environment.Results: 1504 and 1500 proteins were identified in NP and PG respectively. Forty‐eight proteins were exclusively identified in PG, while 52 were identified in NP. Moreover, 35 proteins were more abundant in PG and 29 proteins in NP (twofold change, p < .05). The NP group was mainly represented by proteins from “response to biotic stimuli and other organisms,” “processes of cell death regulation,” “peptidase regulation,” “protein ubiquitination,” and “ribosomal activity” GO categories. The most represented GO categories of the PG group were “assembly of multiprotein complexes,” “catabolic processes,” “lipid metabolism,” and “binding to hemoglobin and haptoglobin.”Conclusions: There are quantitative and qualitative differences in the proteome of GCF from periodontal sites according to the status of clinical progression of periodontitis. Progressive periodontitis sites are characterized by a protein profile associated with catabolic processes, immune response, and response to cellular stress, while stable periodontitis sites show a protein profile mainly related to wound repair and healing processes, cell death regulation, and chaperone‐mediated autophagy. Understanding the etiopathogenic role of these profiles in progressive periodontitis may help to develop new diagnostic and therapeutic approaches.

The University should be considered a favourable space and agent for the training and transmission of values and attitudes related to professionalism, such as responsibility, teamwork and ethical commitment. In addition, dentistry is a profession with a deep social sense that seeks to solve the oral health problems of the population to improve the quality of life. In this context, our aim was to explore the perception of students and patients about the contribution of the curriculum to the development of professionalism and to identify the factors that strengthen and weaken this perception. A qualitative approach was carried out through focus groups and semi-structured interviews with students from the 4th, 5th and 6th year of training and patients treated at the Dental Clinic of our Faculty. In the opinion of patients and students, the factors that debilitate the training in professionalism are associated with weakened professional values/behaviours in the training, the lack of teacher training of the professors and factors of educational environment. On the contrary, factors strengthening the professionalism are mainly related to hallmark values/ professional behaviours trained in the institution and to the good evaluation by patients. The respondents also perceive the implementation of a new curriculum as a positive factor for the training in professionalism. The patients and students interviewed believe that the main strength for the training in professionalism in the institution is the development of adaptability for the future professionals to any social context, especially to a vulnerable one, the ability to solve the problems they face and the responsibility towards the patients and their treatment.

Damage-associated molecular patterns (DAMPs) play a critical role in dendritic cells (DCs) ability to trigger a specific and efficient adaptive immune response for different physiological and pathological scenarios. We have previously identified constitutive DAMPs (HMGB1 and Calreticulin) as well as new putative inducible DAMPs such as Haptoglobin (HP), from a therapeutically used heat shock-conditioned melanoma cell lysate (called TRIMEL). Remarkably, HP was shown to be the most abundant protein in the proteomic profile of heat shock-conditioned TRIMEL samples. However, its relative contribution to the observed DCs phenotype has not been fully elucidated. Human DCs were generated from monocytes isolated from PBMC of melanoma patients and healthy donors. DC lineage was induced with rhIL-4 and rhGM-CSF. After additional stimulation with HP, the proteome of these HP-stimulated cells was characterized. In addition, DCs were phenotypically characterized by flow cytometry for canonical maturation markers and cytokine production. Finally, in vitro transmigration capacity was assessed using Transwell plates. Our results showed that the stimulation with HP was associated with the presence of exclusive and higher relative abundance of specific immune-; energy production-; lipid biosynthesis-; and DAMPs-related proteins. Importantly, HP stimulation enhanced the expression of specific DC maturation markers and pro-inflammatory and Th1-associated cytokines, and an in vitro transmigration of primary human DCs. Taken together, these data suggest that HP can be considered as a new inducible DAMP with an important role in in vitro DC activation for cancer immunotherapy.

The removal of necrotic and vital pulp substrates and microorganisms and their toxins from the root canal system (RCS) has been found to be the basis for a successful endodontic treatment. In this study, our aim was to evaluate the effect of passive ultrasonic irrigation (PUI) on the elimination of the organic remnant tissue from infected, narrow and curved mandibular root canals during their instrumentation. For this purpose, mesiobuccal canals from mandibular first molars were instrumented with the RaCe rotary system, using PUI activation or conventional irrigation (CI) and two apical diameters (#25 and #35). The root canal cleanness of the samples was evaluated by microscopy and using a modified Langeland’s ordinal scale. Parametric and non-parametric statistical analyses and principal coordinates analysis (PCoA) of the samples were performed. When PUI was used, there was a significant reduction of the organic remnant in the apical enlargement of 25 at 2 mm from the apex (p < 0.001). After pooling the groups, regardless of the depth of the observation (2 and 4 mm from the apex), the pair #35 + PUI vs. #25 + CI showed statistically significant differences (p < 0.001). The effect of PUI explained 65% of the overall variance when compared with the CI samples. The use of PUI reduced the organic material of narrow infected and curved root canals with an apical enlargement of #25 and #35. When PUI is not used, a biomechanical instrumentation up to a diameter ≥#35 is recommended.