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Zeshi Li,1– 3,&ast; He Zhang,1– 3,&ast; Sulaiman Baraghtha,4,5,&ast; Jiabao Mu,6,&ast; Yusanjan Matniyaz,2 Xinyi Jiang,1– 3 Kuo Wang,2,7 Dongjin Wang,1– 3,7 Yun Xing Xue2 1Department of Cardio-Thoracic Surgery, Nanjing Drum Tower Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Graduate School of Peking Union Medical College, Nanjing, People’s Republic of China; 2Department of Cardio-Thoracic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, People’s Republic of China; 3Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, People’s Republic of China; 4Department of Cardio-Thoracic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China; 5International School, University of Mannheim, Mannheim, Baden-Württemberg, Federal Republic of Germany; 6School of Data Science, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China; 7Department of Cardio-Thoracic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of XuZhou Medical University, Nanjing, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Yun Xing Xue; Dongjin Wang, Email albert_xue@163.com; wangdongjin@njglyy.comPurpose: The postoperative survival of patients with acute type A aortic dissection (aTAAD) remains unsatisfactory. The current study developed an easy-to-use survival prediction model and calculator.Methods: A total of 496 patients with aTAAD undergoing surgical repair were included in this study. The systemic immune-inflammation index (SII) and other clinical features were collected and subjected to logistic and Cox regression analyses. The survival prediction model was based on Cox regression analyses and exhibited as a nomogram. For convenience of use, the nomogram was further developed into calculator software.Results: We demonstrated that a higher preoperative SII was associated with in-hospital death (OR: 4.116, p < 0.001) and a higher postoperative overall survival rate (HR: 2.467, p < 0.001) in aTAAD patients undergoing surgical repair. A survival prediction model and calculator based on SII and four other clinical features were developed. The overall C-index of the model was 0.743. The areas under the curves (AUCs) of the 1- and 3-month and 1- and 3-year survival probabilities were 0.73, 0.71, 0.71 and 0.72, respectively. The model also showed good calibration and clinical utility.Conclusion: Preoperative SII is significantly associated with postoperative survival. Based on SII and other clinical features, we created the first easy-to-use prediction model and calculator for predicting the postoperative survival rate in aTAAD patients, which showed good prediction performance.Keywords: acute type A aortic dissection, mortality, prediction, systemic immune-inflammation index

Conjugation of an antigen to a carrier protein is widely used for vaccine development. To develop the next generation of conjugate vaccines, we describe here a method for the controlled multi-functionalization of the widely employed carrier protein CRM197 with a carbohydrate-based antigen and an immune potentiator. The approach is based on the selective reduction of one of the disulfides of CRM197 followed by disulfide rebridging employing an appropriately functionalized dibromopyridazinedione. Efficient protein modification required that the reduction and functionalization with a dibromopyridazinedione was performed as a one-step procedure with control over the reaction temperature. Furthermore, ligations were most successful when dibromopyridazinediones were employed having a functional entity such as a TLR7/8 agonist and a cyclooctyne for further modification. Site-specific conjugation avoids modification of T-epitopes of the carrier protein and covalent attachment of an immune potentiator will ensure that cytokines are produced where the vaccine interacts with relevant immune cells resulting in efficient immune potentiation.

Small molecule adjuvants are attractive for enhancing broad protection and durability of immune responses elicited by subunit vaccines. Covalent attachment of an adjuvant to an immunogen is particularly attractive because it simultaneously delivers both entities to antigen presenting cells resulting in more efficient immune activation. There is, however, a lack of methods to conjugate small molecule immune potentiators to viral glycoprotein immunogens without compromising epitope integrity. We describe herein a one-step enzymatic conjugation approach for the covalent attachment of small molecule adjuvants to N-linked glycans of viral glycoproteins. It involves the attachment of an immune potentiator to CMP-Neu5AcN 3 by Cu(I)-catalyzed azide-alkyne 1,3-cycloaddition followed by sialyltransferase-mediated transfer to N-glycans of a viral glycoprotein. The method was employed to modify a native-like HIV envelope trimer with a Toll-like receptor 7/8 agonist. The modification did not compromise Env-trimer recognition by several broadly neutralization antibodies. Electron microscopy confirmed structural integrity of the modified immunogen.

BackgroundInsulin resistance (IR) is a significant risk factor for cardiometabolic diseases and a defining feature of type 2 diabetes mellitus (T2DM). This study aimed to examine the potential value of triglyceride-glucose (TyG) index as a predictor of prognosis in coronary heart disease (CHD) patients with T2DM after coronary artery bypass grafting (CABG) surgery and to facilitate the identification of those at high risk of major adverse cardiovascular events (MACEs) for closer monitoring or possible early intervention.MethodsThis study enrolled 386 T2DM patients who underwent CABG surgery at Nanjing Drum Tower Hospital. Patients were separated into two groups according to the median preoperative TyG Index. The Kaplan-Meier plot was used to compare the rate of MACEs-free survival in T2DM patients after CABG. The independent risk factors for the occurrence of MACEs were investigated using multivariate analysis. Nomogram was used to depict the predictive model.ResultsSignificantly more MACEs occurred in individuals with higher medians of the TyG index (65 (33.7%) vs. 39 (20.2%), p=0.003). TyG index [hazard ratio (HR) 12.926], LVEF [hazard ratio (HR) 0.916], and NYHA functional class III/IV [hazard ratio (HR) 4.331] were identified as independent predictors of MACEs incidence in post-CABG T2DM patients by multivariate analysis. The area under the curve (AUC) for predicting MACEs using the TyG index was 0.89 at five years. Combining the TyG index, LVEF, and NYHA functional class III/IV to build a novel risk assessment model for postoperative MACEs, the AUC climbed to 0.93 at five years. With AUCs, the nomogram comprised of the TyG index, LVEF, and NYHA functional class III/IV demonstrated strong specificity in the training and test sets.ConclusionsThe incidence of MACEs is high among post-CABG T2DM patients with a high TyG index. TyG index improves the diagnostic accuracy of MACEs, especially at long-term follow-up. A high TyG index may serve as an early warning signal for individuals to undertake lifestyle adjustments that can reduce the progression or incidence of MACEs.

The transmission of viruses from animal reservoirs to humans poses great threats to public health. Preparedness for future zoonotic outbreaks requires a fundamental understanding how viruses of animal origin have adapted to binding to a cell surface component/receptor of the new host. In Chapter 2, we describe such specificities of human and animal viruses that engage with O-acetylated sialic acid. Key to these studies was the development of a chemo-enzymatic methodology that can provide almost any sialate-acetylation patterns. The collection of O-acetylated sialoglycans was printed as microarray for receptor specificity determination. It showed host-specific patterns of receptor recognition and revealed that three distinct human respiratory viruses bind 9-O-acetylated α2,8-linked disialoside. Immunofluorescence and cell entry studies support that such glycotope as part of a ganglioside is a functional receptor for human coronaviruses. In Chapter 3, the HE-mediated regioselective de-O-acetylation was extended to the preparation of a panel of O-acetylated N-glycolylneuraminic acid oligosaccharides. The resulted compound library was printed as glycan microarray to investigate receptor binding specificities of viral envelope glycoproteins, including spike proteins and HEs, from animal and human coronaviruses. We have found that the binding pattern of these viral proteins to N-glycolylated sialosides differ considerable from that to N-acetylated counterparts; and that the ability of the spike proteins to tolerated N-glycolyl modification varies among viruses targeting different hosts, whereas the corresponding HEs showed a decrease or loss of binding to N-glycolylated sialosides. In Chapter 4, we describe a chemoenzymatic approach that can readily provide sialoglycan analogs in which acetyl esters at C4 and/or C7 are replaced by stabilizing acetamide moieties. The analogs and their natural counterparts were used to examine ligand requirements of the lectin domain of coronaviral hemagglutinin-esterases (HEs). It revealed that HEs from viruses targeting different host species exhibit different requirements for 7-O-acetylation. It also showed that ester-to-amide perturbation results in decreased or loss of binding. STD-NMR and molecular modeling of the complexes of the HE of BCoV with the acetamido analogs and natural counterparts revealed that binding is governed by the complementarity between acetyl moieties of the sialosides and hydrophobic patches of the lectin. The precise spatial arrangement of these elements is important, and perturbations such as O-to-N change results in substantial loss of binding. Induction of broadly and durably protective response has been the ultimate goal of prophylactic vaccine development. The use of toll-like receptor agonists has been increasingly pursued to augment such immune responses. Furthermore, attachment of these immunomodulating agents to immunogens offers several advantages over combined administration thereof as separate entities. However, there is a lack of general method to conjugate TLR agonists to complex immunogens without compromising important neutralization epitopes. In Chapter 5 we describe a one-step enzymatic conjugation approach which allows for covalent attachment of small molecule immune activators to N-linked glycans of a native-like HIV envelope trimer immunogen. The drug-to-protein ratio can be readily quantified chromatographically. Binding studies with several broadly neutralizing antibodies reveal that the glycan-targeted covalent modification of the glycoprotein immunogen minimally affects its neutralization epitopes.