Search

The end-stage immunopathology of type 1 diabetes resulting in β-cell destruction appears to be strongly dominated by cytotoxic CD8 T lymphocytes (CD8 T cells). However, the mechanism of cytotoxicity used by autoreactive CD8 T cells in the human setting remains unknown. Using type 1 diabetes patient-derived preproinsulin-specific CD8 T-cell clones recognizing either an HLA-A2 (A*0201) or HLA-A24 (A*2402)-restricted epitope (peptide of preproinsulin [PPI](15-24), ALWGPDPAAA; or PPI(3-11), LWMRLLPLL), we assessed the use of conventional mediators of cytotoxicity in the destruction of human β-cells in vitro compared with virus-specific cytotoxic CD8 T-cell clones. We show that PPI-specific CD8 T-cell clones are mainly reliant upon cytotoxic degranulation for inducing β-cell death. Furthermore, we find that in comparison with virus-specific CD8 T cells, there are differences in the killing potency of PPI-specific CD8 T cells that are not due to cell-intrinsic differences, but rather are mediated by differences in strength of signaling by peptide-HLA ligands. The study highlights the regulation of β-cell killing as a potential point for therapeutic control, including the possibility of blocking autoreactive CD8 T-cell function without impacting upon general immune competence. [ABSTRACT FROM AUTHOR]

Type 1 diabetes results from T cell-mediated β-cell destruction. The HLA-A*24 class I gene confers significant risk of disease and early onset. We tested the hypothesis that HLA-A24 molecules on islet cells present preproinsulin (PPI) peptide epitopes to CD8 cytotoxic T cells (CTLs). Surrogate β-cell lines secreting proinsulin and expressing HLA-A24 were generated and their peptide ligandome examined by mass spectrometry to discover naturally processed and HLA-A24-presented PPI epitopes. A novel PPI epitope was identified and used to generate HLA-A24 tetramers and examine the frequency of PPI-specific T cells in new-onset HLA-A*24(+) patients and control subjects. We identified a novel naturally processed and HLA-A24-presented PPI signal peptide epitope (PPI(3-11); LWMRLLPLL). HLA-A24 tetramer analysis reveals a significant expansion of PPI(3-11)-specific CD8 T cells in the blood of HLA-A*24(+) recent-onset patients compared with HLA-matched control subjects. Moreover, a patient-derived PPI(3-11)-specific CD8 T-cell clone shows a proinflammatory phenotype and kills surrogate β-cells and human HLA-A*24(+) islet cells in vitro. These results indicate that the type 1 diabetes susceptibility molecule HLA-A24 presents a naturally processed PPI signal peptide epitope. PPI-specific, HLA-A24-restricted CD8 T cells are expanded in patients with recent-onset disease. Human islet cells process and present PPI(3-11), rendering themselves targets for CTL-mediated killing. [ABSTRACT FROM AUTHOR]

Previous studies have shown that the absence of the collagen-binding integrin α2β1 confers protection against osteoporosis, primarily by enhancing osteoblast-mediated matrix formation, with a particular increase in collagen type I production. This study aimed to elucidate the mechanism underlying this increased matrix production. Our findings demonstrate that osteoblasts lacking integrin α2 secrete a pro-osteogenic factor that activates both TGF-β and BMP signaling pathways. Among these, BMP-2 was identified as the key signaling protein responsible for this effect, as its expression was significantly upregulated during osteoblast differentiation. Moreover, integrin α2 deficiency led to earlier and elevated BMP-2 secretion at the cell surface during osteogenesis, which promoted accelerated osteoblast differentiation. This phenomenon likely contributes to enhanced matrix production in aging animals, providing a protective effect against osteoporosis. To explore the broader implications of this phenotype, we utilized a fracture healing model. In integrin α2-deficient 12 weeks old female mice, elevated serum levels of BMP-2 were detected during the early stages of fracture repair. This upregulation of BMP signaling within the fracture callus accelerated the healing process, resulting in faster formation and mineralization of the cartilaginous callus. Additionally, the elevated BMP-2 levels facilitated earlier differentiation of chondrocytic cells, evidenced by the premature appearance of collagen type II- and type X-positive cells during endochondral ossification. Despite the accelerated healing, the overall biomechanical integrity of the repaired fractures remained uncompromised. Thus, the modulation of integrin α2β1 presents a promising therapeutic target for enhancing fracture repair by regulating BMP-2 signaling in a physiologically relevant manner., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Richard Stange reports financial support was provided by Deutsche Forschungsgemeinschaft. Michael Huelskamp reports financial support was provided by Deutsche Forschungsgemeinschaft. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

We report a model study towards the enantioselective synthesis of the dibenzopyrrocoline alkaloid (-)-cryptowolinol. The key step involves a challenging enantioselective Pd 0 -catalyzed C(sp 3 )-H arylation performed with a chiral NHC ligand, which proceeds via parallel kinetic resolution (PKR). A very efficient PKR process was achieved on a deoxygenated model substrate and was successfully transposed to a potential intermediate en route to (-)-cryptowolinol.

Nuclear magnetic resonance studies of many physiologically important proteins have long been impeded by the necessity to express such proteins in isotope-labeled form in higher eukaryotic cells and the concomitant high costs of providing isotope-labeled amino acids in the growth medium. Economical routes use isotope-labeled yeast or algae extracts but still require expensive isotope-labeled glutamine. Here, we have systematically quantified the effect of 15 N 2 -glutamine on the expression and isotope labeling of different proteins in insect cells. Sufficient levels of glutamine in the medium increase the protein expression by four to five times relative to deprived conditions. 1 H- 15 N nuclear magnetic resonance spectroscopy shows that the 15 N atoms from 15 N 2 -glutamine are scrambled with surprisingly high (60-70%) efficiency into the three amino acids alanine, aspartate, and glutamate. This phenomenon gives direct evidence that the high energy demand of insect cells during baculovirus infection and concomitant heterologous protein expression is predominantly satisfied by glutamine feeding the tricarboxylic acid cycle. To overcome the high costs of supplementing isotope-labeled glutamine, we have developed a robust method for the large-scale synthesis of 15 N 2 -glutamine and partially deuterated 15 N 2 -glutamine-α,β,β-d 3 from inexpensive precursors. An application is shown for the effective large-scale expression of the isotope-labeled β 1 -adrenergic receptor using the synthesized 15 N 2 -glutamine-α,β,β-d 3 ., Competing Interests: Conflict of interest The authors declare no conflict of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Although the rate of infection after the reconstruction of a ruptured anterior cruciate ligament (ACL) is low, prophylactic incubation of the graft with vancomycin (Vanco-wrap or vancomycin soaking) is routinely performed. A cytotoxic effect of vancomycin is reported for several cell types, and the prophylactic treatment might prevent infection but harm the tissue and cells., Aim: A comprehensive study was performed to investigate the effect of vancomycin on tendon tissue and isolated tenocytes using cell viability, molecular and mechanical analysis., Material and Methods: Rat tendons or isolated tenocytes were incubated in increasing concentrations of vancomycin (0-10 mg/mL) for different times, and cell viability, gene expression, histology and Young's modulus were analyzed., Results: The clinically used concentration of vancomycin (5 mg/mL for 20 min) had no negative effect on cell viability in the tendons or the isolated tenocytes, while incubation with the toxic control significantly reduced cell viability. Increasing the concentration and prolonging the incubation time had no negative effect on the cells. The expression of Col1a1 , Col3a1 and the tenocyte markers mohawk , scleraxis and tenomodulin was not affected by the various vancomycin concentrations. The structural integrity as measured through histological and mechanical testing was not compromised., Conclusion: The results proved the safe application of the Vanco-wrap on tendon tissue., Level of Evidence: IV.

Green and sustainable access to chiral and achiral gold-IBiox complexes is reported. The gold complexes were synthesized using a simple, air-tolerant, weak base protocol carried out in a green solvent. Their catalytic activity was examined in the hydroamination of alkynes. The steric protection afforded the gold center by these ligands was quantified using the % V bur model and compared with the most commonly encountered NHCs.

Overuse injuries or acute trauma in joints often lead to painful tendinopathy, and pharmacological treatment effects are limited. The site of the disease is hard to reach with drugs, both systemically and through the skin. Therapeutic gases may close this gap, as they permeate easier through tissues than conventional small molecules. We present a patch device releasing the anti-inflammatory gas carbon monoxide (CO) through the skin to the subcutaneous tendons and tissues. CO is chemically generated upon device activation and its design maximizes CO exposure to the underlying skin and protects the patient from all side and degradation products. The patch delivered CO successfully through the intact skin, granting lasting, subcutaneous CO exposure for up to 16 h. Furthermore, the released CO induced the proliferation of fibroblasts and the polarization of monocytes into anti-inflammatory M2 macrophages. In conclusion, the CO-releasing device might open an entirely new treatment option against tendinopathies in case of a positive outcome of future in vivo studies., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Cancer-induced bone pain (CIBP) is a common and devastating symptom with limited treatment options in patients, significantly affecting their quality of life. The use of rodent models is the most common approach to uncovering the mechanisms underlying CIBP; however, the translation of results to the clinic may be hindered because the assessment of pain-related behavior is often based exclusively on reflexive-based methods, which are only partially indicative of relevant pain in patients. To improve the accuracy and strength of the preclinical, experimental model of CIBP in rodents, we used a battery of multimodal behavioral tests that were also aimed at identifying rodent-specific behavioral components by using a home-cage monitoring assay (HCM). Rats of all sexes received an injection with either heat-deactivated (sham-group) or potent mammary gland carcinoma Walker 256 cells into the tibia. By integrating multimodal datasets, we assessed pain-related behavioral trajectories of the CIBP-phenotype, including evoked and non-evoked based assays and HCM. Using principal component analysis (PCA), we discovered sex-specific differences in establishing the CIBP-phenotype, which occurred earlier (and differently) in males. Additionally, HCM phenotyping revealed the occurrence of sensory-affective states manifested by mechanical hypersensitivity in sham when housed with a tumor-bearing cagemate (CIBP) of the same sex. This multimodal battery allows for an in-depth characterization of the CIBP-phenotype under social aspects in rats. The detailed, sex-specific, and rat-specific social phenotyping of CIBP enabled by PCA provides the basis for mechanism-driven studies to ensure robustness and generalizability of results and provide information for targeted drug development in the future.

Background: Modern medical imaging is a key component of efficient in- and out-patient precision medicine. Conventional radiography and computer tomography scans (CT) are among the most frequent radiologic exams. Medical imaging plays a key role in target-oriented medicine., Objectives: The purpose of this article is to review the anatomy of the hilum of the lung and its most frequent associated pathologies since it is an important gateway of elementary structures of the thorax. Important signs and patterns for image interpretation in different modalities are also reviewed., Results: Thorough knowledge of anatomy, signs, and patterns of pathologies especially in conventional radiography and pitfalls of the more sensitive cross-sectional imaging is essential to support target-oriented patient care., Conclusion: Conventional radiography is affordable and readily available. It is very suitable for pathology screening, i.e., at the hilum of the lung. Cross-sectional imaging specifies diagnostics due to superior anatomic discrimination., (© 2023. The Author(s).)