Comparable humoral and cellular immunity against Omicron variant BA.4/5 of once-boosted BA.1/2 convalescents and twice-boosted COVID-19-naïve individuals.

The fourth vaccination dose confers additional protective immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in individuals with no prior coronavirus disease-19 (COVID-19). However, its immunological benefit against currently circulating BA.4/5 is unclear in individuals who have received a booster shot and been infected with Omicron variant BA.1/2. We analyzed immune responses in whom had been boosted once and did not have COVID-19 (n = 16), boosted once and had COVID-19 when BA.1/2 was dominant in Korea (Hybrid-6M group, n = 27), and boosted twice and did not have COVID-19 (Vx4 group, n = 15). Antibody binding activities against RBDo BA.1 and RBDo BA.4/5 , antigen-specific memory CD4+ and CD8+ T-cell responses against BA.4/5, and B-cell responses against SARS-CoV-2 wild-type did not differ statistically between the Hybrid-6M and Vx4 groups. The humoral and cellular immune responses of the Hybrid-6M group against BA.4/5 were comparable to those of the Vx4 group. Individuals who had been boosted and had an Omicron infection in early 2022 may not have high priority for an additional vaccination.

Distinct Immune Response at 1 Year Post-COVID-19 According to Disease Severity.

Background: Despite the fact of ongoing worldwide vaccination programs for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), understanding longevity, breadth, and type of immune response to coronavirus disease-19 (COVID-19) is still important to optimize the vaccination strategy and estimate the risk of reinfection. Therefore, we performed thorough immunological assessments 1 year post-COVID-19 with different severity. Methods: We analyzed peripheral blood mononuclear cells and plasma samples at 1 year post-COVID-19 in patients who experienced asymptomatic, mild, and severe illness to assess titers of various isotypes of antibodies (Abs) against SARS-CoV-2 antigens, phagocytic capability, and memory B- and T-cell responses. Findings: A total of 24 patients (7, 9, and 8 asymptomatic, mild, and severe patients, respectively) and eight healthy volunteers were included in this study. We firstly showed that disease severity is correlated with parameters of immune responses at 1 year post-COVID-19 that play an important role in protecting against reinfection with SARS-CoV-2, namely, the phagocytic capacity of Abs and memory B-cell responses. Interpretation: Various immune responses at 1 year post-COVID-19, particularly the phagocytic capacity and memory B-cell responses, were dependent on the severity of the prior COVID-19. Our data could provide a clue for a tailored vaccination strategy after natural infection according to the severity of COVID-19.

SARS-CoV-2 is associated with changes in brain structure in UK Biobank.

There is strong evidence of brain-related abnormalities in COVID-191-13. However, it remains unknown whether the impact of SARS-CoV-2 infection can be detected in milder cases, and whether this can reveal possible mechanisms contributing to brain pathology. Here we investigated brain changes in 785 participants of UK Biobank (aged 51-81 years) who were imaged twice using magnetic resonance imaging, including 401 cases who tested positive for infection with SARS-CoV-2 between their two scans-with 141 days on average separating their diagnosis and the second scan-as well as 384 controls. The availability of pre-infection imaging data reduces the likelihood of pre-existing risk factors being misinterpreted as disease effects. We identified significant longitudinal effects when comparing the two groups, including (1) a greater reduction in grey matter thickness and tissue contrast in the orbitofrontal cortex and parahippocampal gyrus; (2) greater changes in markers of tissue damage in regions that are functionally connected to the primary olfactory cortex; and (3) a greater reduction in global brain size in the SARS-CoV-2 cases. The participants who were infected with SARS-CoV-2 also showed on average a greater cognitive decline between the two time points. Importantly, these imaging and cognitive longitudinal effects were still observed after excluding the 15 patients who had been hospitalised. These mainly limbic brain imaging results may be the in vivo hallmarks of a degenerative spread of the disease through olfactory pathways, of neuroinflammatory events, or of the loss of sensory input due to anosmia. Whether this deleterious effect can be partially reversed, or whether these effects will persist in the long term, remains to be investigated with additional follow-up.

Exploring the Link Between Vitamin D Deficiency and Cytokine Storms in COVID-19 Patients: An In Silico Analysis.

COVID-19 has become a global infectious pandemic affecting the entire world with complications related to the lungs and compromised immune systems. Recently, cytokine storms, which are hallmarks of the disease, have been identified in most COVID-19 patients. In addition, vitamin D deficiency is increasingly appearing to be another element exposing COVID-19 patients to a preferential increase in their symptoms. In an effort to identify a possible link between cytokine storms and vitamin D deficiency to streamline a possible treatment, an in silico analysis using bioinformatics approach was performed using collections of highly expressed cytokines in both severe acute respiratory syndrome and COVID-19 patients (commonly elevated cytokines) as well as vitamin D deficiency-associated genes (VD). Gene Multiple Association Network Integration Algorithm was used for network interactions, whereas the Enrichr enrichment analysis tool was used for biological functions. The network analysis GLay clustering results indicated the vitamin D receptor as a possible link between these two groups. Furthermore, cell chemotaxis and chemotactic-related features were identified as significantly affected pathways, which serve as possible key players mitigating cytokine storms under low vitamin D availability.

Longitudinal Analysis of Human Memory T-Cell Response According to the Severity of Illness up to 8 Months After Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

BACKGROUND: Understanding the memory T-cell response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial for assessing the longevity of protective immunity after SARS-CoV-2 infection or coronavirus disease 2019 (COVID-19) vaccination. However, the longitudinal memory T-cell response up to 8 months post-symptom onset (PSO) according to the severity of illness is unknown. METHODS: We analyzed peripheral blood mononuclear cells (PBMCs) from healthy volunteers or patients with COVID-19 who experienced asymptomatic, mild, or severe illness at 2, 5, and 8 months PSO. SARS-CoV-2 spike, nucleocapsid, and membrane protein-stimulated PBMCs were subjected to flow cytometry analysis. RESULTS: A total of 24 patients (7 asymptomatic, 9 with mild disease, and 8 with severe disease) and 6 healthy volunteers were analyzed. SARS-CoV-2-specific OX40+CD137+CD4+ T cells and CD69+CD137+CD8+ T cells persisted at 8 months PSO. Also, antigen-specific cytokine-producing or polyfunctional CD4+ T cells were maintained for up to 8 months PSO. Memory CD4+ T-cell responses tended to be greater in patients who had severe illness than in those with mild or asymptomatic disease. CONCLUSIONS: Memory response to SARS-CoV-2, based on the frequency and functionality, persists for 8 months PSO. Further investigations involving its longevity and protective effect from reinfection are warranted.

Impacts of biomedical hashtag-based Twitter campaign: #DHPSP utilization for promotion of open innovation in digital health, patient safety, and personalized medicine

The open innovation hub Digital Health and Patient Safety Platform (DHPSP) was recently established with the purpose to invigorate collaborative scientific research and the development of new digital products and personalized solutions aiming to improve human health and patient safety. In this study, we evaluated the effectiveness of a Twitter-based campaign centered on using the hashtag #DHPSP to promote the visibility of the DHPSP initiative. Thus, tweets containing #DHPSP were monitored for five weeks for the period 20.10.2020-24.11.2020 and were analyzed with Symplur Signals (social media analytics tool). In the study period, a total of 11,005 tweets containing #DHPSP were posted by 3,020 Twitter users, generating 151,984,378 impressions. Analysis of the healthcare stakeholder-identity of the Twitter users who used #DHPSP revealed that the most of participating user accounts belonged to individuals or doctors, with the top three user locations being the United States (501 users), the United Kingdom (155 users), and India (121 users). Analysis of co-occurring hashtags and the full text of the posted tweets further revealed that the major themes of attention in the #DHPSP Twitter-community were related to the coronavirus disease 2019 (COVID-19), medicine and health, digital health technologies, and science communication in general. Overall, these results indicate that the #DHPSP initiative achieved high visibility and engaged a large body of Twitter users interested in the DHPSP focus area. Moreover, the conducted campaign resulted in an increase of DHPSP member enrollments and website visitors, and new scientific collaborations were formed. Thus, Twitter campaigns centered on a dedicated hashtag prove to be a highly efficient tool for visibility-promotion, which could be successfully utilized by healthcare-related open innovation platforms or initiatives.