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Introduction: SARS-CoV-2 pandemic still poses a significant burden on global health and economy, especially for symptoms persisting beyond the acute disease. COVID-19 manifests with various degrees of severity and the identification of early biomarkers capable of stratifying patient based on risk of progression could allow tailored treatments., Methods: We longitudinally analyzed 67 patients, classified according to a WHO ordinal scale as having Mild, Moderate, or Severe COVID-19. Peripheral blood samples were prospectively collected at hospital admission and during a 6-month follow-up after discharge. Several subsets and markers of the innate and adaptive immunity were monitored as putative factors associated with COVID-19 symptoms., Results: More than 50 immunological parameters were associated with disease severity. A decision tree including the main clinical, laboratory, and biological variables at admission identified low NK-cell precursors and CD14 + CD91 + monocytes, and high CD8 + Effector Memory T cell frequencies as the most robust immunological correlates of COVID-19 severity and reduced survival. Moreover, low regulatory B-cell frequency at one month was associated with the susceptibility to develop long COVID at six months, likely due to their immunomodulatory ability., Discussion: These results highlight the profound perturbation of the immune response during COVID-19. The evaluation of specific innate and adaptive immune-cell subsets allows to distinguish between different acute and persistent COVID-19 symptoms., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Noviello, De Lorenzo, Chimienti, Maugeri, De Lalla, Siracusano, Lorè, Rancoita, Cugnata, Tassi, Dispinseri, Abbati, Beretta, Ruggiero, Manfredi, Merolla, Cantarelli, Tresoldi, Pastori, Caccia, Sironi, Marzinotto, Saliu, Ghezzi, Lampasona, Vicenzi, Cinque, Manfredi, Scarlatti, Dellabona, Lopalco, Di Serio, Malnati, Ciceri, Rovere-Querini and Bonini.)

Type 1 diabetes (T1D) presents a persistent medical challenge, demanding innovative strategies for sustained glycemic control and enhanced patient well-being. Beta cells are specialized cells in the pancreas that produce insulin, a hormone that regulates blood sugar levels. When beta cells are damaged or destroyed, insulin production decreases, which leads to T1D. Allo Beta Cell Transplantation has emerged as a promising therapeutic avenue, with the goal of reinstating glucose regulation and insulin production in T1D patients. However, the path to success in this approach is fraught with complex immunological hurdles that demand rigorous exploration and resolution for enduring therapeutic efficacy. This exploration focuses on the distinct immunological characteristics inherent to Allo Beta Cell Transplantation. An understanding of these unique challenges is pivotal for the development of effective therapeutic interventions. The critical role of glucose regulation and insulin in immune activation is emphasized, with an emphasis on the intricate interplay between beta cells and immune cells. The transplantation site, particularly the liver, is examined in depth, highlighting its relevance in the context of complex immunological issues. Scrutiny extends to recipient and donor matching, including the utilization of multiple islet donors, while also considering the potential risk of autoimmune recurrence. Moreover, unanswered questions and persistent gaps in knowledge within the field are identified. These include the absence of robust evidence supporting immunosuppression treatments, the need for reliable methods to assess rejection and treatment protocols, the lack of validated biomarkers for monitoring beta cell loss, and the imperative need for improved beta cell imaging techniques. In addition, attention is drawn to emerging directions and transformative strategies in the field. This encompasses alternative immunosuppressive regimens and calcineurin-free immunoprotocols, as well as a reevaluation of induction therapy and recipient preconditioning methods. Innovative approaches targeting autoimmune recurrence, such as CAR Tregs and TCR Tregs, are explored, along with the potential of stem stealth cells, tissue engineering, and encapsulation to overcome the risk of graft rejection. In summary, this review provides a comprehensive overview of the inherent immunological obstacles associated with Allo Beta Cell Transplantation. It offers valuable insights into emerging strategies and directions that hold great promise for advancing the field and ultimately improving outcomes for individuals living with diabetes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Caldara, Tomajer, Monti, Sordi, Citro, Chimienti, Gremizzi, Catarinella, Tentori, Paloschi, Melzi, Mercalli, Nano, Magistretti, Partelli and Piemonti.)

Induced pluripotent stem cells (iPSCs) represent a source from which β cells can be derived for diabetes replacement therapy. However, their application may be hindered by immune-mediated responses. Although abrogation of major histocompatibility complex class I (MHC-I) can address this issue, it may trigger natural killer (NK) cells through missing-self recognition mechanisms. By profiling the relevant NK-activating ligands on iPSCs during in vitro differentiation into pancreatic β cells, we find that they express high levels of B7-H3 and CD155. Hypothesizing that such surface ligands could be involved in the amplification of NK-activating signals following missing-self, we generate MHC-I-deprived B7-H3 -/- , CD155 -/- , and B7-H3 -/- /CD155 -/- iPSCs. All engineered lines correctly differentiate into insulin-secreting β cells and are protected from cell lysis mediated by CD16 dim and CD16 + NK subpopulations both in vitro and in vivo in NSG mice. Our data support targeted disruption of NK-activating ligands to enhance the transplant compatibility of MHC-I -/- iPSC pancreatic derivatives., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background Aims: Induced pluripotent stem cells (iPSCs) have the capacity to generate β cells in vitro, but the differentiation is incomplete and generates a variable percentage of off-target cells. Single-cell RNA sequencing offers the possibility of characterizing the transcriptional dynamics throughout differentiation and determining the identity of the final differentiation product., Methods: Single-cell transcriptomics data were obtained from four stages across differentiation of iPSCs into β cells and from human donor islets., Results: Clustering analysis revealed that iPSCs undertake a full endoderm commitment, and the obtained endocrine pancreatic cells have high homology with mature islets. The iPSC-derived β cells were devoid of pluripotent residual cells, and the differentiation was pancreas-specific, as it did not generate ectodermal or mesodermal cells. Pseudotime trajectory identified a dichotomic endocrine/non-endocrine cell fate and distinct subgroups in the endocrine branch., Conclusions: Future efforts to produce β cells from iPSCs must aim not only to improve the resulting endocrine cell but also to avoid differentiation into non-pancreatic endoderm cells., (Copyright © 2020 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Background: Despite the recent introduction of new drugs and the development of innovative multi-target treatments, the prognosis of pancreatic ductal adenocarcinoma (PDAC) remains very poor. Even when PDAC is resectable, the rate of local or widespread disease recurrence remains particularly high. Currently, reliable prognostic biomarkers of recurrence are lacking. We decided to explore the potential usefulness of pancreatic developmental regulators as biomarkers of PDAC relapse., Methods: We analyzed by quantitative real-time PCR the mRNA of selected factors involved either in pancreatic organogenesis (ISL1, NEUROD1, NGN3, NKX2.2, NKX6.1, PAX4, PAX6, PDX1 and PTF1α) or associated with terminally committed pancreatic cells (CHGA, CHGB, GAD2, GCG, HNF6α, INS, KRT19, SYP) in 17 PDAC cell lines and in frozen tumor samples from 41 PDAC patients., Results: High baseline levels of the ISL1, KRT19, PAX6 and PDX1 mRNAs in PDAC cell lines, were risk factors for time-dependent xenograft appearance after subcutaneous injection in CD1-Nude mice. Consistently, in human PDAC samples, high levels of KRT19 mRNA were associated with reduced overall survival and earlier recurrence. Higher levels of PDX1 or PAX6 mRNAs were instead associated with a higher frequency of local recurrence., Conclusions: Our findings suggest that selected factors associated with pancreas development or its terminal differentiation might be implicated in mechanisms of PDAC progression and/or metastatic spread and that the measurement of their mRNA in tumors might be potentially used to improve patient prognostic stratification and prediction of the relapse site., (Copyright © 2018 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Background: New sources of insulin-secreting cells are strongly in demand for treatment of diabetes. Induced pluripotent stem cells (iPSCs) have the potential to generate insulin-producing cells (iβ). However, the gene expression profile and secretory function of iβ still need to be validated in comparison with native β cells., Methods: Two clones of human iPSCs, reprogrammed from adult fibroblasts through integration-free Sendai virus, were differentiated into iβ and compared with donor pancreatic islets and EndoC-βH1, an immortalized human β cell line., Results: Both clones of iPSCs differentiated into insulin + cells with high efficiency (up to 20%). iβ were negative for pluripotency markers (Oct4, Sox2, Ssea4) and positive for Pdx1, Nkx6.1, Chromogranin A, PC1/3, insulin, glucagon and somatostatin. iβ basally secreted C-peptide, glucagon and ghrelin and released insulin in response either to increasing concentration of glucose or a depolarizing stimulus. The comparison revealed that iβ are remarkably similar to donor derived islets in terms of gene and protein expression profile and similar level of heterogeneity. The ability of iβ to respond to glucose instead was more related to that of EndoC-βH1., Discussion: We demonstrated that insulin-producing cells generated from iPSCs recapitulate fundamental gene expression profiles and secretory function of native human β cells.

The oxidation of a series of aryl diphenylmethyl sulfides (4-X-C6H4SCH(C6H5)2, where X = OCH3 (1), X = CH3 (2), X = H (3), and X = CF3 (4)) promoted by the nonheme iron(IV)-oxo complex [(N4Py)Fe(IV)═O](2+) occurs by an electron transfer-oxygen transfer (ET-OT) mechanism as supported by the observation of products (diphenylmethanol, benzophenone, and diaryl disulfides) deriving from α-C-S and α-C-H fragmentation of radical cations 1(+•)-4(+•), formed besides the S-oxidation products (aryl diphenylmethyl sulfoxides). The fragmentation/S-oxidation product ratios regularly increase through a decrease in the electron-donating power of the aryl substituents, that is, by increasing the fragmentation rate constants of the radical cations as indicated by a laser flash photolysis (LFP) study of the photochemical oxidation of 1-4 carried out in the presence of N-methoxyphenanthridinium hexafluorophosphate (MeOP(+)PF6(-)).

Objective: To show the possible role of abdominal scintigraphy in the diagnosis of intra-abdominal pathology and its accuracy in detecting ectopic gastric mucosa in pts with intestinal bleeding and/or abdominal pain., Method: 99m-Tc-pertechnetate scintigraphy was performed on 54 pts with a history of intestinal bleeding and/or abdominal pain with the following results: 11 true positive pts (9 with Meckel's D; 2 with enteric duplication) all of whom were confirmed at surgery; 14 false positive pts in whom the presence and location of entero-colic (12 pts), renal (2 pts), and uterine (1 pt) pathology were determined; 28 true negative pts; an arca of persistent low activity was found in the bladder of 1 pt which later proved to be a ureterocele at ultrasound; 1 false negative pt who was found to have Meckel's D at surgery., Conclusion: In this case series abdominal scintigraphy was effective in diagnosing 26/54 pts and, in particular, in diagnosis, 23/28 pts in recurrent intestinal bleeding. Given that its sensitivity is not negligible and that it is an exam which is scarcely invasive, easy to perform and interpret and requires low irradiation (definitely lower than barium enemas, digestive tract radiography and CT), abdominal scintigraphy should be the first examination to be performed in all pts with intestinal bleeding and/or abdominal pain, especially children, whose diagnosis cannot be simply or rapidly determined.

Hyperventilation (HV) and ergonovine (E) tests were carried out in a group of 32 patients with variant angina to compare their sensitivity and to correlate the results with the activity of the disease. The HV test was positive in 84% of the patients and E in 94% of them; the percentage of positive responses to HV was similar to that to E (96% vs 100%) in the patients with daily attacks, while it was lower (55% vs 77%) in those with sporadic attacks. All 27 patients with a positive HV also had a positive response to E, while of the five patients with a negative HV, two also had a negative response to E and the other three had a positive E at a higher dose than that of the patients with daily attacks. The incidence of chest pain and of ST-segment elevation or depression or T-wave positivization was similar during the two tests; however, spontaneous remission of ischaemia was more frequent after HV than after E and ventricular arrhythmias less frequent during the HV test. At the onset of myocardial ischaemia pH was significantly higher compared with basal values (7.51 +/- 0.07 vs 7.38 +/- 0.05, P less than 0.001), while double product was not significantly different compared with basal (10.0 +/- 2.4 vs 9.2 +/- 2.1).(ABSTRACT TRUNCATED AT 250 WORDS)