A ubiquitin-independent proteasome pathway controls activation of the CARD8 inflammasome

CARD8 is a pattern-recognition receptor that forms a caspase-1-activating inflammasome. CARD8 undergoes constitutive autoproteolysis, generating an N-terminal (NT) fragment with a disordered region and a ZU5 domain and a C-terminal (CT) fragment with UPA and CARD domains. Dipeptidyl peptidase 8 and dipeptidyl peptidase 9 inhibitors, including Val-boroPro, accelerate the degradation of the NT fragment via a poorly characterized proteasome-mediated pathway, thereby releasing the inflammatory CT fragment from autoinhibition. Here, we show that the core 20S proteasome, which degrades disordered and misfolded proteins independent of ubiquitin modification, controls activation of the CARD8 inflammasome. In unstressed cells, we discovered that the 20S proteasome degrades just the NT disordered region, leaving behind the folded ZU5, UPA, and CARD domains to act as an inhibitor of inflammasome assembly. However, in Val-boroPro–stressed cells, we show the 20S proteasome degrades the entire NT fragment, perhaps due to ZU5 domain unfolding, freeing the CT fragment from autoinhibition. Taken together, these results show that the susceptibility of the CARD8 NT domain to 20S proteasome-mediated degradation controls inflammasome activation.     

Adverse events of special interest and mortality following vaccination with mRNA (BNT162b2) and inactivated (CoronaVac) SARS-CoV-2 vaccines in Hong Kong: A retrospective study

BackgroundSafety monitoring of coronavirus disease 2019 (COVID-19) vaccines is crucial during mass vaccination rollout to inform the choice of vaccines and reduce vaccine hesitancy. Considering the scant evidence directly comparing the safety profiles of mRNA and inactivated SARS-CoV-2 vaccines, this territory-wide cohort study aims to compare the incidence of various adverse events of special interest (AESIs) and all-cause mortality between CoronaVac (inactivated vaccine) and BNT162b2 (mRNA-based vaccine). Our results can help vaccine recipients make an informed choice.Methods and findingsA retrospective, population-based cohort of individuals who had received at least 1 dose of BNT162b2 or CoronaVac from 23 February to 9 September 2021 in Hong Kong, and had data linkage to the electronic medical records of the Hong Kong Hospital Authority, were included. Those who had received mixed doses were excluded. Individuals were observed from the date of vaccination (first or second dose) until mortality, second dose vaccination (for first dose analysis), 21 days after vaccination, or 30 September 2021, whichever came first. Baseline characteristics of vaccinated individuals were balanced between groups using propensity score weighting. Outcome events were AESIs and all-cause mortality recorded during 21 days of post-vaccination follow-up after each dose, except anaphylaxis, for which the observation period was restricted to 2 days after each dose. Incidence rate ratios (IRRs) of AESIs and mortality comparing between CoronaVac and BNT162b2 recipients were estimated after each dose using Poisson regression models. Among 2,333,379 vaccinated individuals aged 18 years or above, the first dose analysis included 1,308,820 BNT162b2 and 955,859 CoronaVac recipients, while the second dose analysis included 1,116,677 and 821,560 individuals, respectively. The most frequently reported AESI among CoronaVac and BNT162b2 recipients was thromboembolism (first dose: 431 and 290 per 100,000 person-years; second dose: 385 and 266 per 100,000 person-years). After the first dose, incidence rates of overall AESIs (IRR = 0.98, 95% CI 0.89–1.08, p = 0.703) and mortality (IRR = 0.96, 95% CI 0.63–1.48, p = 0.868) associated with CoronaVac were generally comparable to those for BNT162b2, except for Bell palsy (IRR = 1.95, 95% CI 1.12–3.41, p = 0.018), anaphylaxis (IRR = 0.34, 95% CI 0.14–0.79, p = 0.012), and sleeping disturbance or disorder (IRR = 0.66, 95% CI 0.49–0.89, p = 0.006). After the second dose, incidence rates of overall AESIs (IRR = 0.97, 95% CI 0.87–1.08, p = 0.545) and mortality (IRR = 0.85, 95% CI 0.51–1.40, p = 0.516) were comparable between CoronaVac and BNT162b2 recipients, with no significant differences observed for specific AESIs. The main limitations of this study include residual confounding due to its observational nature, and the possibility of its being underpowered for some AESIs with very low observed incidences.ConclusionsIn this study, we observed that the incidences of AESIs (cumulative incidence rate of 0.06%–0.09%) and mortality following the first and second doses of CoronaVac and BNT162b2 vaccination were very low. The safety profiles of the vaccines were generally comparable, except for a significantly higher incidence rate of Bell palsy, but lower incidence rates of anaphylaxis and sleeping disturbance or disorder, following first dose CoronaVac versus BNT162b2 vaccination. Our results could help inform the choice of inactivated COVID-19 vaccines, mainly administered in low- and middle-income countries with large populations, in comparison to the safety of mRNA vaccines. Long-term surveillance on the safety profile of COVID-19 vaccines should continue.

In a retrospective study, Carlos King Ho Wong, Kristy Tsz Kwan Lau, and colleagues study adverse events reported following COVID-19 vaccination in Hong Kong.     

Investigation on glycosylation patterns of proteins from human liver cancer cell lines based on the multiplexed proteomics technology

Glycosylation, a very important post-translational modification of proteins, is increasingly coming into notice. However, large-scale, throughput investigations on glycosylated proteins are few. We applied a sensitive and fast fluorescence-based multiplexed proteomics (MP) technology which included two-dimensional gel electrophoresis (2-DE) followed by the fluorescence staining of glycoprotein and mass spectrometry identification for the purpose of constructing glycoprotein databases of the typical human hepatocellular carcinoma cell lines including Hep3B cell line without metastasis and MHCC97H with highly metastatic potential as well as the control non-tumor Chang liver cell. 74+/-2 (n=3), 78+/-3 (n=3) and 72+/-5 (n=3) glycoprotein spots were detected on 2-DE gels from Chang liver, Hep3B and MHCC97H cell sample using this MP technique, respectively. In all, 80 glycoproteins from three cell lines were successfully identified via peptide mass profiling using MALDI-TOF-MS/MS and the identified glycoproteins were annotated to our databases. In addition, we also found the glycosylation pattern differences among these three cell lines. The protein glycosylation alteration would be have great significance for the diagnosis of HCC and prediction of its metastasis. This study described the construction of glycosylation patterns of proteins and glycoproteome databases of human liver cells by the novel technological platform. The glycoproteome databases also provide essential basis for following study.     

Tropism of avian influenza A (H5N1) in the upper and lower respiratory tract

Poor human-to-human transmission of influenza A H5N1 virus has been attributed to the paucity of putative sialic acid alpha2-3 virus receptors in the epithelium of the human upper respiratory tract, and thus to the presumed inability of the virus to replicate efficiently at this site. We now demonstrate that ex vivo cultures of human nasopharyngeal, adenoid and tonsillar tissues can be infected with H5N1 viruses in spite of an apparent lack of these receptors.     

Secreted Hydrolytic and Haemolytic Activities of Malassezia Clinical Strains

Mycopathologia - Malassezia yeasts are opportunistic pathogens associated with a number of skin diseases in animals and humans. The free fatty acids released through these organisms’ lipase...     

cnvCapSeq: detecting copy number variation in long-range targeted resequencing data

Targeted resequencing technologies have allowed for efficient and cost-effective detection of genomic variants in specific regions of interest. Although capture sequencing has been primarily used for investigating single nucleotide variants and indels, it has the potential to elucidate a broader spectrum of genetic variation, including copy number variants (CNVs). Various methods exist for detecting CNV in whole-genome and exome sequencing datasets. However, no algorithms have been specifically designed for contiguous target sequencing, despite its increasing importance in clinical and research applications. We have developed cnvCapSeq, a novel method for accurate and sensitive CNV discovery and genotyping in long-range targeted resequencing. cnvCapSeq was benchmarked using a simulated contiguous capture sequencing dataset comprising 21 genomic loci of various lengths. cnvCapSeq was shown to outperform the best existing exome CNV method by a wide margin both in terms of sensitivity (92.0 versus 48.3%) and specificity (99.8 versus 70.5%). We also applied cnvCapSeq to a real capture sequencing cohort comprising a contiguous 358 kb region that contains the Complement Factor H gene cluster. In this dataset, cnvCapSeq identified 41 samples with CNV, including two with duplications, with a genotyping accuracy of 99%, as ascertained by quantitative real-time PCR.     

Different associations of white matter lesions with depression and cognition

ABSTRACT: BACKGROUND: To test the hypothesis that white matter lesions (WML) are primarily associated with regional frontal cortical volumes, and to determine the mediating effects of these regional frontal cortices on the associations of WML with depressive symptoms and cognitive dysfunction. METHODS: Structural brains MRIs were performed on 161 participants: cognitively normal, cognitive impaired but not demented, and demented participants. Lobar WML volumes, regional frontal cortical volumes, depressive symptom severity, and cognitive abilities were measured. Multiple linear regression analyses were used to identify WML volume effects on frontal cortical volume. Structural equation modeling was used to determine the MRI-depression and the MRI-cognition path relationships. RESULTS: WML predicted frontal cortical volume, particularly in medial orbirtofrontal cortex, irrespective of age, gender, education, and group status. WML directly predicted depressive score, and this relationship was not mediated by regional frontal cortices. In contrast, the association between WML and cognitive function was indirect and mediated by regional frontal cortices. CONCLUSIONS: These findings suggest that the neurobiological mechanisms underpinning depressive symptoms and cognitive dysfunction in older adults may differ.