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Autophagy is a cellular process that degrades cytoplasmic cargo by engulfing it in a double-membrane vesicle, known as the autophagosome, and delivering it to the lysosome. The ATG12-5-16L1 complex is responsible for conjugating members of the ubiquitin-like ATG8 protein family to phosphatidylethanolamine in the growing autophagosomal membrane, known as the phagophore. ATG12-5-16L1 is recruited to the phagophore by a subset of the phosphatidylinositol 3-phosphate-binding seven-bladedß -propeller WIPI proteins. We determined the crystal structure of WIPI2d in complex with the WIPI2 interacting region (W2IR) of ATG16L1 comprising residues 207-230 at 1.85 Å resolution. The structure shows that the ATG16L1 W2IR adopts an alpha helical conformation and binds in an electropositive and hydrophobic groove between WIPI2 ß-propeller blades 2 and 3. Mutation of residues at the interface reduces or blocks the recruitment of ATG12-5-16 L1 and the conjugation of the ATG8 protein LC3B to synthetic membranes. Interface mutants show a decrease in starvation-induced autophagy. Comparisons across the four human WIPIs suggest that WIPI1 and 2 belong to a W2IR-binding subclass responsible for localizing ATG12-5-16 L1 and driving ATG8 lipidation, whilst WIPI3 and 4 belong to a second W34IR-binding subclass responsible for localizing ATG2, and so directing lipid supply to the nascent phagophore. The structure provides a framework for understanding the regulatory node connecting two central events in autophagy initiation, the action of the autophagic PI 3-kinase complex on the one hand and ATG8 lipidation on the other.

Background: Transfusion of red cell concentrates (RCCs) is an integral therapy after severe hemorrhage or trauma. Prehospital transfusion offers an immediate intervention in emergency cases. Air ambulance-based prehospital transfusion, already used in different countries, is currently established in Germany. Limited information is available for regulatory-compliant transport logistics of RCCs and their quality after repeated air rescue missions. Thus, the aim of this study was (i) to validate regulatory-compliant logistics and (ii) to assess product quality, analyzing biochemical parameters and RBC morphology., Study Design and Methods: Due to regulatory requirements, we adapted a rotation system of 1 day transport, 1 day quarantine storage and 1 day storage over the entire RCC shelf life. RCCs transported on air rescue missions (flight group) were compared against a control group, treated identically except for helicopter transport. RCCs were visually inspected, and their temperature was documented throughout the entire rotation cycles. RCCs at the end of shelf life (end point samples) were assessed for levels of hemoglobin, hematocrit, free hemoglobin, hemolysis, mean corpuscular volume, potassium and pH. In addition, morphological changes were assessed using flow morphometry., Results: In total 81 RCCs were assessed in the flight group and 50 in the control group. Within the flight group, 30 RCCs were transfused. RCCs were dispatched on average 11 times (7-13 times). The average flight time was 18.3 h (6.6-28.8 h). The rotation system ensured adherence to regulatory guidelines, especially compliance to storage conditions of +2 to +6°C of intermediate storage. Biochemical and morphological quality parameters did not exhibit any changes upon repeated air rescue missions. A correlation with respect to the flight time was not observed either., Discussion: The quality of RCCs after repeated air rescue missions is noninferior to control samples regarding biochemical and morphological parameters. The product quality is within German regulations for up to 42 days of storage. The logistics and maintenance of the thermal conditions are safe and feasible. Thus, a rotation system of RCCs offers a regulatory-compliant option to supply air rescue missions with RCCs to allow life-saving prehospital transfusions at the incident scene., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2022 by S. Karger AG, Basel.)

Background: Red blood cells (RBCs) stored for transfusions can lyse over the course of the storage period. The lysis is traditionally assumed to occur via the formation of spiculated echinocyte forms, so that cells that appear smoother are assumed to have better storage quality. We investigate this hypothesis by comparing the morphological distribution to the hemolysis for samples from different donors., Methods: Red cell concentrates were obtained from a regional blood bank quality control laboratory. Out of 636 units processed by the laboratory, we obtained 26 high hemolysis units and 24 low hemolysis units for assessment of RBC morphology. The association between the morphology and the hemolysis was tested with the Wilcoxon-Mann-Whitney U test., Results: Samples with high stomatocyte counts ( p = 0.0012) were associated with increased hemolysis, implying that cells can lyse via the formation of stomatocytes., Conclusion: RBCs can lyse without significant echinocyte formation. Lower degrees of spiculation are not a good indicator of low hemolysis when RBCs from different donors are compared., Competing Interests: The authors have no conflicts of interest., (Copyright © 2020 by S. Karger AG, Basel.)

Background: In older people, quantification of risk of reattendance after emergency department (ED) discharge is important to provide adequate post ED discharge care in the community to appropriately targeted patients at risk., Methods: We reanalysed data from a prospective observational study, previously used for derivation of a nomogram for stratifying people aged 65 and older at risk for ED reattendance. We investigated the potential effect of comorbidity load and frailty by adding the Charlson or Elixhauser comorbidity index and a ten-item frailty measure from our data to develop four new nomograms. Model I and model F built on the original nomogram by including the frailty measure with and without the addition of the Charlson comorbidity score; model E adapted for efficiency in the time-constrained environment of ED was without the frailty measure; and model P manually constructed in a purposeful stepwise manner and including only statistically significant variables. Areas under the ROC curve of models were compared. The primary outcome was any ED reattendance within 28 days of discharge., Results: Data from 1357 patients were used. The point estimate of the respective areas under ROC were 0.63 (O), 0.63 (I), 0.68 (E), 0.71 (P) and 0.63 (F)., Conclusion: Addition of a comorbidity index to our previous model improves stratifying elderly at risk of ED reattendance. Our frailty measure did not demonstrate any additional predictive benefit.

The phenotype and functional characteristics of skin-infiltrating lymphocytes in beta-lactam antibiotic-induced vesiculobullous exanthemas were studied in vivo and in vitro. Immunohistochemical analysis demonstrated that CD8+ T lymphocytes were the predominant epidermal T-cell subset in these reactions. Epidermal T lymphocytes were isolated and expanded for in vitro studies. Fluorescence-activated cell sorter analysis showed the majority of epidermal T cells to be CD3+, T-cell receptor alpha/beta+, CD4-, CD8+, and HLA-DR+, which correlated with the predominance of epidermal CD8+ T lymphocytes found in situ. Three CD8+ epidermal T-cell clones derived from cutaneous lesions proliferated in response to penicillin-pulsed autologous antigen-presenting cells but not allogeneic antigen-presenting cells, indicating that those clones were antigen and major histocompatibility complex specific. All T-cell clones produced significant amounts of interleukin-2, interferon-gamma, and granulocyte-macrophage colony-stimulating factor. Additionally, the T-cell clones displayed cytotoxicity against epidermal cells in lectin-mediated cytotoxicity and against B-cell lines in T-cell receptor-triggered cytotoxicity. These data demonstrate the presence of epidermal drug-specific CD8+ T cells in bullous drug reactions. Because these CD8+ T cells have a cytotoxic potential, they may contribute to the necrosis of keratinocytes associated with drug-induced blister formation.

Parenchymal hepatocytes from neonatal rats were isolated, cultured about 24 h, exposed to cadmium with or without calcium, and processed for scanning electron microscopy. To assess the severity of cadmium-induced changes, exposed hepatocytes were categorized based upon the extent of morphological damage. Differences in surface blebbing, alterations in microvilli, variations in the degree of swelling, and changes in cell shape were used to categorize the severity of cell damage. A double-blind morphometric analysis (a geometricostatistical processing of two-dimensional data for the collection of three-dimensional information) of cellular changes was conducted for each exposure time and for each concentration of cadmium in the presence or absence of calcium. Significant decreases occurred in the percent relative volume of normal, flattened cells present in cultures exposed for 30 min to 50 or 100 microM cadmium in the absence of calcium. In contrast, the percent relative volume of severely damaged spherical cells was significantly increased after exposure to solutions containing 50 or 100 microM cadmium and lacking calcium. Percent relative volume of intermediate cells (which were slightly swollen and showed changes in microvillar number) was significantly increased following a 30 min exposure to all cadmium concentrations in the absence of calcium. The examination of hepatocytes exposed for 60 min showed that the degree of cadmium-induced cytotoxicity was more severe in the absence of calcium than was the case for the hepatocyte cultures exposed for 30 min: approximately 30% more spherical cells and 30% fewer flattened cells were present if cultures were exposed in the absence of calcium for 60 min compared to those exposed for 30 min. The degree of blebbing was significantly greater at all cadmium concentrations in the absence of calcium. The presence of calcium, therefore, reduced cadmium-induced cytotoxicity in primary cultures of rat hepatocytes subjected to morphometric analysis after scanning electron microscopy.