Distinguishing activated T regulatory cell and T conventional cells by single cell technologies

Resting conventional T cells (Tconv) can be distinguished from T regulatory cells (Treg) by the canonical markers FOXP3, CD25 and CD127. However, the expression of these proteins alters after T‐cell activation leading to overlap between Tconv and Treg. The objective of this study was to distinguish resting and antigen‐responsive T effector (Tconv) and Treg using single‐cell technologies. CD4⁺ Treg and Tconv cells were stimulated with antigen and responsive and non‐responsive populations processed for targeted and non‐targeted single‐cell RNAseq. Machine learning was used to generate a limited set of genes that could distinguish responding and non‐responding Treg and Tconv cells and which was used for single‐cell multiplex qPCR and to design a flow cytometry panel. Targeted scRNAseq clearly distinguished the four‐cell populations. A minimal set of 27 genes was identified by machine learning algorithms to provide discrimination of the four populations at >95% accuracy. In all, 15 of the genes were validated to be differentially expressed by single‐cell multiplex qPCR. Discrimination of responding Treg from responding Tconv could be achieved by a flow cytometry strategy that included staining for CD25, CD127, FOXP3, IKZF2, ITGA4, and the novel marker TRIM which was strongly expressed in Tconv and weakly expressed in both responding and non‐responding Treg. A minimal set of genes was identified that discriminates responding and non‐responding CD4⁺ Treg and Tconv cells and, which have identified TRIM as a marker to distinguish Treg by flow cytometry.

The transCampus Metabolic Training Programme Explores the Link of SARS-CoV-2 Virus to Metabolic Disease

Currently, we are experiencing a true pandemic of a communicable disease by the virus SARS-CoV-2 holding the whole world firmly in its grasp. Amazingly and unfortunately, this virus uses a metabolic and endocrine pathway via ACE2 to enter our cells causing damage and disease. Our international research training programme funded by the German Research Foundation has a clear mission to train the best students wherever they may come from to learn to tackle the enormous challenges of diabetes and its complications for our society. A modern training programme in diabetes and metabolism does not only involve a thorough understanding of classical physiology, biology and clinical diabetology but has to bring together an interdisciplinary team. With the arrival of the coronavirus pandemic, this prestigious and unique metabolic training programme is facing new challenges but also new opportunities. The consortium of the training programme has recognized early on the need for a guidance and for practical recommendations to cope with the COVID-19 pandemic for the community of patients with metabolic disease, obesity and diabetes. This involves the optimal management from surgical obesity programmes to medications and insulin replacement. We also established a global registry analyzing the dimension and role of metabolic disease including new onset diabetes potentially triggered by the virus. We have involved experts of infectious disease and virology to our faculty with this metabolic training programme to offer the full breadth and scope of expertise needed to meet these scientific challenges. We have all learned that this pandemic does not respect or heed any national borders and that we have to work together as a global community. We believe that this transCampus metabolic training programme provides a prime example how an international team of established experts in the field of metabolism can work together with students from all over the world to address a new pandemic.

Beneficial Effect of U-74389 G and Sildenafil in An Experimental Model of Flap Ischemia/Reperfusion Injury in Swine. Histological and Biochemical Evaluation of the Model

Purpose of the study: Tissue reconstruction after burns, tumor excisions, infections or injuries is a frequent surgical challenge to avoid Ischemia-reperfusion injury. Lazaroids and sildenafil, through their mechanisms of action, have been studied for their protective effects on various organs subjected to IRI. In this study, we aimed to evaluate the therapeutic potential of U-74389G and sildenafil in a swine model of ischemia and reperfusion injury of latissimus dorsi flap. Materials and methods: Forty-two Landrace male pigs, weighing 28-35 kg, were equally (n = 6) randomized into the following groups: (a) Group I: control, (b) Group II: administration of U-74389G after ischemia, (c) Group III: administration of sildenafil after ischemia, (d) Group IV: administration of U-74389G and sildenafil after ischemia, (e) Group V: administration of U-74389G prior to ischemia, (f) Group VI: administration of sildenafil prior to ischemia, and (g) Group VII: administration of U-74389G and sildenafil prior to ischemia. Blood and tissue sampling was conducted before ischemia, 15 and 30 min after occlusion, 30, 60, 90, and 120 min after reperfusion. Results: Statistically significant reduction (p < 0.05) was detected in lymphocytes and polymorphonuclear leukocytes concentrations as well as in the appearance of edema after histopathologic evaluation of the ischemic tissue, especially in the groups of combined treatment. Measurements of malondialdeyde and tumour necrosis factor alpha in tissues revealed a significant decrease (p < 0.001) of these markers in the treatment groups when compared to the control, particularly in the latest estimated timepoints. Conclusions: The synergistic action of U-74389G and sildenafil seems protective and promising in cases of flap IRI during tissue reconstruction surgery.

Tetranectin expression in gastric adenocarcinomas

AIMS

The aim was to analyze the immunohistochemical localization of tetranectin in gastric adenocarcinomas and the adjacent tissues of the wall of the stomach.

METHODS AND RESULTS

Forty cases of gastric adenocarcinomas were stained by the indirect immunoperoxidase method. Of the ten cases of mucinous signet ring cell carcinomas 5 showed high, 3 moderate and 2 low tetranectin expression. Of the ten cases of well-differentiated intestinal type adenocarcinomas (ITA) 4 showed moderate regional, 3 low regional and 3 negative tetranectin expression. Of the ten cases of moderately-differentiated ITA 3 showed moderate regional, 4 low regional and 3 negative tetranectin expression. Of the ten cases of poorly-differentiated ITA 4 showed focal low and 6 negative tetranectin expression. Overall, the mucinous signet ring carcinomas showed significantly higher tetranectin expression compared to ITA (chi2 = 3.95, p<0.05). In contrast, no significant relationship was found between tetranectin expression and the degree of differentiation in ITA (chi2 = 2.5, p>0.05). In all cases, the perineoplastic desmoplastic reactive stroma showed high expression of tetranectin intra- and extracellularly. The mast cells and goblet cells in the areas of intestinal metaplasia showed high tetranectin expression.

CONCLUSIONS

This study shows that: a) tetranectin is produced and deposited extracellularly in the desmoplastic peritumoral stroma of infiltrating gastric adenocarcinomas; b) tetranectin is more highly expressed by the mucinous signet ring cell carcinomas compared to ITA; and c) the amount of tetranectin produced by the ITA is unrelated with the degree of tumor differentiation.

Hamartomas of the breast

Hamartomas of the breast are rare tumor-like lesions composed of ducts, lobules, fat, and fibrous tissue. The clinical and pathologic findings of six cases of patients ranging in age from 19 to 63 years are reported. Diagnosis is difficult, and we emphasize that fine needle aspiration and cytology of the smears is not diagnostic for hamartomas.