Bladder cancer has notable heterogeneity. The urine-based fluorescence in situ hybridization (FISH) test can detect bladder cancer noninvasively. In this study, we aimed to construct a nomogram based on FISH results and clinical features (referred to as the FISH–clinical model) to predict the overall survival (OS) of bladder cancer patients following radical cystectomy (RC). A total of 261 eligible patients were enrolled for this study. The SYSMH cohort was divided into training (n = 138) and internal validation (n = 70) sets; the SYSUTH cohort was used for external validation (n = 53). Multivariate Cox proportional hazards regression was applied for FISH–clinical model construction, and model performance was evaluated according to analyses of calibration, discrimination ability, and clinical usefulness. FISH-identified chromosome 7 and 17 aneuploidies correlated significantly with increased pT stage; the former was associated with lymph node metastasis. Six variables, age, tumor size, pT stage, lymphovascular invasion, chromosome 7 aneuploidy, and p16 locus loss, were found to be independent predictors of OS and were incorporated into our FISH–clinical model. The model demonstrated good calibration and discrimination, with C-indexes (95

Background: Dual-energy computed tomography (DECT) is purported to accurately distinguish uric acid stones from non-uric acid stones. However, whether DECT can accurately discriminate ammonium urate stones from uric acid stones remains unknown. Therefore, we aimed to explore whether they can be accurately identified by DECT and to develop a radiomics model to assist in distinguishing them.Methods: This research included two steps. For the first purpose to evaluate the accuracy of DECT in the diagnosis of uric acid stones, 178 urolithiasis patients who underwent preoperative DECT between September 2016 and December 2019 were enrolled. For model construction, 93, 40, and 109 eligible urolithiasis patients treated between February 2013 and October 2022 were assigned to the training, internal validation, and external validation sets, respectively. Radiomics features were extracted from non-contrast CT images, and the least absolute shrinkage and selection operator (LASSO) algorithm was used to develop a radiomics signature. Then, a radiomics model incorporating the radiomics signature and clinical predictors was constructed. The performance of the model (discrimination, calibration, and clinical usefulness) was evaluated.Results: When patients with ammonium urate stones were included in the analysis, the accuracy of DECT in the diagnosis of uric acid stones was significantly decreased. Sixty-two percent of ammonium urate stones were mistakenly diagnosed as uric acid stones by DECT. A radiomics model incorporating the radiomics signature, urine pH value, and urine white blood cell count was constructed. The model achieved good calibration and discrimination {area under the receiver operating characteristic curve (AUC; 95% confidence interval [CI]), 0.944 (0.899–0.989)}, which was internally and externally validated with AUCs of 0.895 (95% CI, 0.796–0.995) and 0.870 (95% CI, 0.769–0.972), respectively. Decision curve analysis revealed the clinical usefulness of the model.Conclusions: DECT cannot accurately differentiate ammonium urate stones from uric acid stones. Our proposed radiomics model can serve as a complementary diagnostic tool for distinguishing themin vivo.

Background:The prognostic significance of tumor size with adrenocortical carcinoma (ACC) patients has not yet been thoroughly evaluated. Our objective was to investigate the influence of tumor size on prognostic value in adult ACC patients. Methods:The Surveillance, Epidemiology and End Results Program (SEER) was employed to identify adult ACC patients who had been diagnosed from 2004 to 2015. The "X-Tile" program determined the optimal cutoff value of tumor size. Cancer-specific survival (CSS) and overall survive (OS) were estimated. The survival outcomes and risk factors were analyzed by the Kaplan-Meier methods and the multivariable cox regression respectively. Results:A total 426 adult ACC patients were included. Univariable and multivariable cox analysis revealed age, larger tumor size and metastasis as consistent predictors of lower CSS and OS. The optimal cutoff value of tumor size was identified as 8.5 cm using X-tile software, and Kaplan-Meier method showed dramatic prognostic difference between patients with larger tumors (＞8.5 cm) and smaller tumors (≤8.5 cm) (log-rank test, P < 0.001). Subgroup analyses revealed no statistical significance and a consistent proportionate effect of tumor size on CSS and OS across all eight pre-specified subgroups. Interestingly, an additional subgroup analysis showed that ACC patients could not benefit from chemotherapy in terms of CSS and OS. Conclusion:The study suggests that tumor size is a crucial prognostic factor in ACC patients and a cutoff value 8.5 cm might indicate a poor outcome. Given the limitations of the available data, it is challenging to conclusively determine the benefit of chemotherapy in adult ACC patients across different tumor size ranges.

OBJECTIVES:The objective of this study was to investigate the dynamic profiles of myocardial injury biomarkers and their association with mortality in patients with severe fever with thrombocytopenia syndrome (SFTS). DESIGN:A retrospective cohort study. SETTINGS:Union Hospital in Wuhan, China. PATIENTS:A total of 580 patients with SFTS, observed between May 2014 and December 2021, were included in the final analysis. INTERVENTIONS:None. MEASUREMENTS AND MAIN RESULTS:In total, 580 patients with SFTS were enrolled in the study, comprised of 469 survivors and 111 nonsurvivors, with a 21-day fatality rate of 19.1%. The elevation of troponin I (TnI) was observed in 61.6% patients (357/580) with SFTS upon admission, and 68.4% patients (397/580) developed an abnormal TnI level during hospitalization. Multivariate logistic regression identified age, viral load, platelet count, creatinine level, and TnI level as potential risk factors for mortality in patients with SFTS. The results of restricted cubic splines revealed that when the TnI level (baseline TnI: 1.55 [lg (ng/L+1)], peak value: TnI 1.90 [lg (ng/L+1)]) exceeded a certain threshold, the predicted mortality of patients with SFTS increased alongside the rise in TnI levels. Mortality rate surpassed 40% among patients with SFTS with TnI greater than or equal to 10 times the upper limit of normal at admission (43.8%) or during hospitalization (41.7%). Older age, a history of cardiovascular disease, and higher d -dimer levels were potential risk factors for elevated TnI levels in patients with SFTS. CONCLUSIONS:Elevated TnI levels were prevalent among patients with SFTS and were strongly associated with an increased risk of mortality.

Abstract Background Non-muscle invasive bladder cancer (NMIBC) is known for its elevated recurrence rate, necessitating an enhancement in the current risk stratification for recurrence. The urine-based fluorescence in situ hybridization (FISH) assay has emerged as a noninvasive auxiliary tool for detecting bladder cancer. The aim of this study was to explore the potential relationship between the preoperative FISH assay and recurrence, and to develop a FISH-clinical nomogram for predicting the recurrence-free survival (RFS) in NMIBC patients. Methods In total, 332 eligible patients were enrolled from two hospitals. The SYSMH cohort was randomly assigned to the training set (n = 168) and the validation set I (n = 72) at a ratio of 7:3, while the SYSUTH cohort was allocated to the validation set II (n = 92). The correlation between the preoperative FISH assay and recurrence was determined through the Cox regression analysis. The least absolute shrinkage and selection operator (LASSO) Cox regression algorithm was used for model construction. The performance of the model was assessed by its discrimination, calibration, and clinical usefulness. Results We uncovered that chromosome 7 aneuploidy, p16 locus loss, number of the positive FISH sites, and the FISH test result were significantly associated with tumor recurrence. Then, a FISH-clinical nomogram incorporating the FISH test result, T stage, associated CIS, tumor grade, and tumor status was developed. It showed favorable calibration and discrimination with a C-index of 0.683 (95%CI, 0.611–0.756) in the training set, which was confirmed in the validation set I and validation set II with C-indexes of 0.665 (95%CI, 0.565–0.765) and 0.778 (95%CI, 0.665–0.891), respectively. Decision curve analysis revealed the clinical usefulness of the nomogram. Moreover, our proposed nomogram significantly outperformed the guideline-recommended EORTC and CUETO scoring models. Conclusion Our study confirmed the prognostic value of the preoperative FISH assay and proposed a FISH-clinical nomogram to predict RFS in NMIBC patients. Our nomogram can serve as a more precise tool for recurrence risk stratification, which may optimize disease management in bladder cancer and improve patient prognosis.

COVID-19, caused by SARS-CoV-2, has resulted in hundreds of millions of infections and millions of deaths worldwide. Preliminary results exhibited excellent efficacy of SARS-CoV-2 vaccine in preventing hospitalization and severe disease. However, data on inactivated vaccine-induced immune responses of naturally infected patients are limited. Here, we characterized SARS-CoV-2 RBD-specific IgG (anti-S-RBD IgG) and neutralizing antibodies (NAbs) against SARS-CoV-2 wild type and variants of concerns (VOCs), as well as RBD-specific IgG-secreting B cells and antigen-specific T cells respectively in 51 SARS-CoV-2 recovered subjects and 63 healthy individuals. In SARS-CoV-2 recovered patients, a single dose vaccine is sufficient to reactivate robust anti-S-RBD IgG and NAbs. The neutralizing capacity against VOCs increased significantly post-vaccination no matter healthy individuals or SARS-CoV-2 recovered patients. In addition, RBD-specific IgG-secreting B cells in SARS-CoV-2 recovered patients were significantly higher than that in healthy vaccine recipients. After the vaccine booster, the frequencies of specific IFN-γ+ CD4+ T cell, IL-2+ CD4+ T cell, and TNF-α+ CD4+ T cell responses were significantly increased in SARS-CoV-2 recovered patients. Our data highlighted the safety and utility of SARS-CoV-2 inactivated vaccine and demonstrated that robust humoral and cellular immune response can be reactivated by one-dose inactivated vaccine in SARS-CoV-2 recovered patients.

PurposeImmune checkpoint blockade agents were shown to provide a survival advantage in urothelial carcinoma, while some patients got minimal benefit or side effects. Therefore, we aimed to investigate the prognostic value of m6A methylation regulators, and developed a nomogram for predicting the response to atezolizumab in urothelial carcinoma patients.MethodsA total of 298 advanced urothelial carcinoma patients with response data in the IMvigor210 cohort were included. Differential expressions of 23 m6A methylation regulators in different treatment outcomes were conducted. Subsequently, a gene signature was developed in the training set using the least absolute shrinkage and selection operator (LASSO) regression. Based on the multivariable logistic regression, a nomogram was constructed by incorporating the gene signature and independent clinicopathological predictors. The performance of the nomogram was assessed by its discrimination, calibration, and clinical utility with internal validation.ResultsSix m6A methylation regulators, including IGF2BP1, IGF2BP3, YTHDF2, HNRNPA2B1, FMR1, and FTO, were significantly differentially expressed between the responders and non-responders. These six regulators were also significantly correlated with the treatment outcomes. Based on the LASSO regression analysis, the gene signature consisting of two selected m6A methylation regulators (FMR1 and HNRNPA2B1) was constructed and showed favorable discrimination. The nomogram integrating the gene signature, TMB, and PD-L1 expression on immune cells, showed favorable calibration and discrimination in the training set (AUC 0.768), which was confirmed in the validation set (AUC 0.755). Decision curve analysis confirmed the potential clinical usefulness of the nomogram.ConclusionsThis study confirmed the prognostic value of FMR1 and HNRNPA2B1, and constructed a nomogram for individualized prediction of the response to atezolizumab in patients with urothelial carcinoma, which may aid in making treatment strategies.

Background and Aims: Patients with severe fever with thrombocytopenia syndrome (SFTS) commonly show liver function impairment. This study aimed to characterize the liver function indices in SFTS patients and investigate their association with mortality. Methods: Clinical information and laboratory results of 459 laboratory-confirmed SFTS patients, including 78 deceased and 381 surviving patients, were retrospectively analyzed. To explore the infectivity of SFTS caused by novel Bunyavirus (SFTSV) in hepatocytes, Huh7 human hepatoma cells were infected with various concentrations of SFTSV in vitro. Results: The proportion of SFTS patients developing liver injury during hospitalization was 73.2% (336/459); the hepatocellular injury was the predominant type. The median time to occurrence of liver injury from disease onset was 8 d. Liver injury in the deceased group occurred earlier than that in the surviving group. Alanine aminotransferase (ALT) level between 2-5 times upper limit of normal (ULN) at 4-6 d and between 5-15 ULN at 7-12 d of disease course were independent predictors of mortality. Alkaline phosphatase (ALP) >2 ULN at 7-9 d and elevated ALP at 10-12 days after disease onset were risk factors for death. ALT and aspartate transaminase (AST) levels were correlated with lymphocyte count and platelet-to-lymphocyte ratio (PLR). Total bilirubin (TB), ALT, AST levels showed positive correlation with viral load. In the in vitro experiment, SFTSV infected and replicated inside Huh7 cells. Conclusions: Liver injury is common in SFTS patients. ALT and ALP were independent predictors of SFTS-related mortality. Frequent monitoring and evaluation of liver function indices are needed for SFTS patients.

While the immunogenicity of inactivated vaccines against coronavirus disease 2019 (COVID‐19) has been characterized in several well-conducted clinical trials, real-world evidence concerning immune responses against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) raised by such vaccines is currently missing. Here, we comprehensively characterized various parameters of SARS-CoV-2-specific cellular and humoral immune responses induced by inactivated COVID-19 vaccines in 126 individuals under real-world conditions. After two doses of vaccination, S-receptor binding domain IgG (S-RBD IgG) and neutralizing antibody (NAb) were detected in 87.06% (74/85) and 78.82% (67/85) of individuals, respectively. Female participants developed higher concentrations of S-RBD IgG and NAb compared to male vaccinees. Interestingly, a longer dosing interval between the first and second vaccination resulted in a better long-term SARS-CoV-2 S-RBD IgG response. The frequencies of CD4+ T cells that produce effector cytokines (IFN-γ, IL-2, and TNF-α) in response to stimulation with peptide pools corresponding to the SARS-CoV-2 spike (S), nucleocapsid (N) or membrane (M) protein were significantly higher in individuals received two doses of vaccine than those received one dose of vaccine and unvaccinated individuals. S, N, or M-specific CD4+ and CD8+ T cell responses were detectable in 95.83% (69/72) and 54.16% (39/72) of double-vaccinated individuals, respectively. The longitudinal analysis demonstrated that CD4+ T cell responses recognizing S, N, and M waned quickly after a single vaccine dose, but were boosted and became more sustained following a second dose. Overall, we provide a comprehensive characterization of immune responses induced by inactivated COVID-19 vaccines in real-world settings, suggesting that both humoral and cellular SARS-CoV-2-specific immunity are elicited in the majority of individuals after two doses of inactivated COVID-19 vaccines.

Abstract Background The incidence of breast cancer ranks the first among female malignant tumors. Although the effect of breast cancer treatment strategies has been very ideal and the mortality rate of breast cancer has decreased, some patients are still not sensitive to these, which eventually leads to rapid recurrence, metastasis and poor prognosis. Ferroptosis is a kind of Regulated cell death, which induced by accumulation of lipid peroxidation products and Reactive Oxygen Species (ROS). It is quite different from apoptosis and autophagy in cell morphological characteristics and biochemical indicators. According to the latest studies, ferroptosis can reduce the activity of GPX4 (Gutathione Peroxidase 4) in cells and accumulate ROS and lipid Peroxidase products through iron metabolism, ROS metabolism, amino acid metabolism and lipid metabolism, etc., thus causing ferroptosis. Ferroptosis is a hotspot in the study of drug resistance and metastasis of breast cancer. Simvastatin is a kind of commonly used oral cholesterol-lowering drugs, belongs to the HMG CoA reductase inhibitors. Some clinical studies have shown that statins can reduce the risk of a variety of cancers, including breast cancer, and the risk of recurrence. Other basic experiment show lipophilic statins have anti-cancer effect. Simvastatin is the most lipophilic of all statins in use. Recent studies have found that simvastatin can be used in combination with docetaxel to enhance the effect of chemotherapy in prostate cancer, but has not been reported in breast cancer. In this study, we investigated whether simvastatin could induce ferroptosis in breast cancer by inhibiting GPX4 and play the role of chemotherapy sensitization in combination with docetaxel. Methods (1) CCK8 assay was used for cell proliferation in vitro by simvastatin and docetaxel in breast cancer cells MDA-MB-231 and MCF-7. (2) The anti-cancer effect of simvastatin in vivo was verified by xenograft experiments in nude mice. (3) GPX4 mRNA and protein levels were detected by qPCR and Western blot. (4) GPXs activity test, ROS level test and MDA level test were used for ferroptosis detection.(5) the expression of ferroptosis-related genes ACSL4, PTGS2 and NOX1 was detected by qPCR.(6) anti-tumor effect of simvastatin combined with docetaxel in breast cancer cells mda-mb-231 and McF-7 was detected in vitro by CCK8 method.(7) By MDA-MB-231 tumor xenograft models surveyed anti-tumor activity of simvastatin and docetaxel. Results CCK8 results showed that simvastatin significantly inhibited cell proliferation in breast cancer cells MDA-MB-231 and MCF-7 (P<0.001), with the IC50 values of MDA-MB-231 was 4.67um and MCF-7 was 81.53um,. In the xenograft experiments of nude mice, it was found that compared with the control group, the tumor volume of the simvastatin group was significantly reduced. In qPCR and Western blot, simvastatin was found to significantly inhibit GPX4 mRNA and protein expression. Compared with the control group, in breast cancer cells MDA-MB-231 and MCF-7, simvastatin can reduce the activity of GPXs and increase the level of ROS and MDA, thus causing ferroptosis in breast cancer cells. qPCR showed that ferroptosis -related gene ACSL4 and PTGS2, which are related to lipid metabolism, and ROS metabolism were significantly increased. In the xenograft experiments of nude mice, it was found that compared with the control group and the single drug group, the tumor volume of simvastatin combined with docetaxel group was significantly reduced. Conclusion Simvastatin can inhibit the proliferation of breast cancer cells both in vivo and in vitro, inhibit the expression of breast cancer cell MDA-MB-231 and MCF-7 GPX4, and induce ferroptosis. Besides, simvastatin sensitizes the effect of docetaxel. Citation Format: Sihong Lu, Nan Shao, Jong Bi, Ying Lin. Simvastatin induces ferroptosis in breast cancer cells by inhibiting GPX4 and sensitizes chemotherapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS18-44.

Background: Patients with cirrhosis have an increased risk of short-term mortality, however, few studies quantify the association between neutrophil-to-lymphocyte ratio (NLR) and 90-day transplant-free mortality in cirrhotic patients.Methods: We prospectively analyzed 3,970 patients with chronic liver diseases from two multicenter cohorts in China (January 2015 to December 2016 and July 2018 to January 2019). Restricted cubic splines (RCS) were used to analyze the relation of NLR and all-causes 90-day transplant-free mortality in cirrhosis.Results: A total of 2,583 cirrhotic patients were enrolled in our study. Restricted cubic splines showed that the odds ratio (OR) of all causes 90-day transplant-free mortality started to increase rapidly until around NLR 6.5, and then was relatively flat (p for non-linearity <0.001). The risk of 90-day transplant-free mortality in cirrhotic patients with NLR < 6.5 increased with an increment of 23% for every unit increase in NLR (p < 0.001). The patients with NLR < 4.5 had the highest risk (OR: 2.34, 95% CI 1.66–3.28). In multivariable-adjusted stratified analyses, the increase in the incidence of 90-day transplant-free mortality with NLR increasing was consistent (OR >1.0) across all major prespecified subgroups, including infection group (OR: 1.04, 95% CI 1.00–1.09) and non-infection (OR: 1.06, 95% CI 1.02–1.11) group. The trends for NLR and numbers of patients with organ failure varied synchronously and were significantly increased with time from day 7 to day 28.Conclusions: We found a non-linear association between baseline NLR and the adjusted probability of 90-day transplant-free mortality. A certain range of NLR is closely associated with poor short-term prognosis in patients with cirrhosis.

Long-term antibody responses and neutralizing activities in response to SARS-CoV-2 infection are not yet clear. Here we quantify immunoglobulin M (IgM) and G (IgG) antibodies recognizing the SARS-CoV-2 receptor-binding domain (RBD) of the spike (S) or the nucleocapsid (N) protein, and neutralizing antibodies during a period of 6 months from COVID-19 disease onset in 349 symptomatic COVID-19 patients who were among the first be infected world-wide. The positivity rate and magnitude of IgM-S and IgG-N responses increase rapidly. High levels of IgM-S/N and IgG-S/N at 2-3 weeks after disease onset are associated with virus control and IgG-S titers correlate closely with the capacity to neutralize SARS-CoV-2. Although specific IgM-S/N become undetectable 12 weeks after disease onset in most patients, IgG-S/N titers have an intermediate contraction phase, but stabilize at relatively high levels over the 6 month observation period. At late time points, the positivity rates for binding and neutralizing SARS-CoV-2-specific antibodies are still >70%. These data indicate sustained humoral immunity in recovered patients who had symptomatic COVID-19, suggesting prolonged immunity.

Importance: Hepatic encephalopathy is a severe complication, and its contribution to clinical adverse outcomes in patients with acute-on-chronic liver diseases from the East is unclear. Objective: We aimed to investigate the impact of hepatic encephalopathy on clinical characteristics and adverse outcomes in prospective and multicenter cohorts of patients with acute-on-chronic liver diseases. Design: We conducted a cohort study of two multicenter prospective cohorts. Setting: China. Participants: Acute-on-chronic liver disease patients with various etiologies. Exposure: The diagnosis and severity of hepatic encephalopathy were assessed using the West Haven scale. Main Outcome Measure: The correlation between clinical adverse outcomes and varying hepatic encephalopathy grades was analyzed in the target patients. Results: A total of 3,949 patients were included, and 340 of them had hepatic encephalopathy. The incidence of hepatic encephalopathy was higher in patients with alcohol consumption (9.90%) than in those with hepatitis B virus infection (6.17%). The incidence of 28- and 90-day adverse outcomes increased progressively from hepatic encephalopathy grades 1–4. Logistic regression analysis revealed that hepatic encephalopathy grades 3 and 4 were independent risk factors for the 28- and 90-day adverse outcome in the fully adjusted model IV. Stratified analyses showed similar results in the different subgroups. Compared to grades 1–2 and patients without hepatic encephalopathy, those with grade 3 hepatic encephalopathy had a significant increase in clinical adverse outcomes, independent of other organ failures. Conclusions and Relevance: Hepatic encephalopathy grades 3–4 were independent risk factors for 28- and 90-day adverse outcomes. Hepatic encephalopathy grade 3 could be used as an indicator of brain failure in patients with acute-on-chronic liver disease.

Urolithiasis is a common urological disease, and treatment strategy options vary between different stone types. However, accurate detection of stone composition can only be performed in vitro. The management of infection stones is particularly challenging with yet no effective approach to pre-operatively identify infection stones from non-infection stones. Therefore, we aimed to develop a radiomic model for preoperatively identifying infection stones with multicenter validation. In total, 1198 eligible patients with urolithiasis from three centers were divided into a training set, an internal validation set, and two external validation sets. Stone composition was determined by Fourier transform infrared spectroscopy. A total of 1316 radiomic features were extracted from the pre-treatment Computer Tomography images of each patient. Using the least absolute shrinkage and selection operator algorithm, we identified a radiomic signature that achieved favorable discrimination in the training set, which was confirmed in the validation sets. Moreover, we then developed a radiomic model incorporating the radiomic signature, urease-producing bacteria in urine, and urine pH based on multivariate logistic regression analysis. The nomogram showed favorable calibration and discrimination in the training and three validation sets (area under the curve [95% confidence interval], 0.898 [0.840-0.956], 0.832 [0.742-0.923], 0.825 [0.783-0.866], and 0.812 [0.710-0.914], respectively). Decision curve analysis demonstrated the clinical utility of the radiomic model. Thus, our proposed radiomic model can serve as a non-invasive tool to identify urinary infection stones in vivo, which may optimize disease management in urolithiasis and improve patient prognosis.

Evidence suggests that platelets may directly interact with SARS-CoV-2, raising the concern whether ACE2 receptor plays a role in this interaction. The current study showed that SARS-CoV-2 interacts with both platelets and megakaryocytes despite the limited efficiency. Abundance of the conventional receptor ACE2 and alternative receptors or co-factors for SARS-CoV-2 entry was characterized in platelets from COVID-19 patients and healthy persons as well as human megakaryocytes based on laboratory tests or previously reported RNA-seq data. The results suggest that SARS-CoV-2 interacts with platelets and megakaryocytes via ACE2-independent mechanism and may regulate alternative receptor expression associated with COVID-19 coagulation dysfunction.

Major advances have been made in understanding the dynamics of humoral immunity briefly after the acute coronavirus disease 2019 (COVID-19). However, knowledge concerning long-term kinetics of antibody responses in convalescent patients is limited. During a one-year period post symptom onset, we longitudinally collected 162 samples from 76 patients and quantified IgM and IgG antibodies recognizing the nucleocapsid (N) protein or the receptor binding domain (RBD) of the spike protein (S). After one year, approximately 90% of recovered patients still had detectable SARS-CoV-2-specific IgG antibodies recognizing N and RBD-S. Intriguingly, neutralizing activity was only detectable in ~43% of patients. When neutralization tests against the E484K-mutated variant of concern (VOC) B.1.351 (initially identified in South Africa) were performed among patients who neutralize the original virus, the capacity to neutralize was even further diminished to 22.6% of donors. Despite declining N- and S-specific IgG titers, a considerable fraction of recovered patients had detectable neutralizing activity one year after infection. However, neutralizing capacities, in particular against an E484K-mutated VOC were only detectable in a minority of patients one year after symptomatic COVID-19. Our findings shed light on the kinetics of long-term immune responses after natural SARS-CoV-2 infection and argue for vaccinations of individuals who experienced a natural infection to protect against emerging VOC.

Approximately half of the SARS-CoV-2 infections occur without apparent symptoms, raising questions regarding long-term humoral immunity in asymptomatic individuals. Plasma levels of immunoglobulin G (IgG) and M (IgM) against the viral spike or nucleoprotein were determined for 25,091 individuals enrolled in a surveillance program in Wuhan, China. We compared 405 asymptomatic individuals who mounted a detectable antibody response with 459 symptomatic COVID-19 patients. The well-defined duration of the SARS-CoV-2 endemic in Wuhan allowed a side-by-side comparison of antibody responses following symptomatic and asymptomatic infections without subsequent antigen re-exposure. IgM responses rapidly declined in both groups. However, both the prevalence and durability of IgG responses and neutralizing capacities correlated positively with symptoms. Regardless of sex, age, and body weight, asymptomatic individuals lost their SARS-CoV-2-specific IgG antibodies more often and rapidly than symptomatic patients did. These findings have important implications for immunity and favour immunization programs including individuals after asymptomatic infections.

Background: Chest CT image guided handling of pneumonia patients with negative RT-PCR detection of SARS-CoV-2 in high endemic areas is still controversial b