Deciphering immunological imprinting in the context of COVID-19 Coronavirus Disease COVID ImmunologicalImprinting COVID19Vaccine SARSCoV2 AntigenicSeniority BackBoosting OriginalAntigenicSin ImmuneMemory VaccineEfficacy ImmunityCP
Primer: Immunological imprinting: Understanding COVID-19. Image Credit: Lightspring / Shutterstock
The term original antigenic "sin" seems to have a negative connotation. It points to the development of a lifelong antigenic bias following the first exposure to an antigen in childhood. Although reactivity towards the original strain is higher than towards newer strains, it is yet feasible to exploit OAS with the right vaccine formulation. Further, the researchers discussed the seemingly conflicting observations in the published scientific literature on OAS, i.e.
Another noteworthy feature of immune imprinting is that all immunological reactivity differences triggered by it could not be translated into epidemiological differences. Hence, variable susceptibility to infections could easily be considered an 'epidemiological imprint' that the first antigen exposure leaves at the population level.
Another term is 'back-boosting,' which refers to an elevation in antibody titers towards antigens encountered previously. Longitudinal studies used this term to describe antibody responses post-exposure to antigenically related pathogens, e.g., a modified influenza virus strain used in a vaccine or a newer strain causing re-infection.
While immunological data could help understand the observed epidemiological patterns, vice versa, i.e., extrapolating immunological results to clinical outcomes is not feasible. Considering the classic seroprotection curve, either of two possibilities arise:ii) comparable antibody titer fold variation could have markedly varying protective effects. Importantly, concerning disease severity, immune protection is multifactorial and not quantifiable by a single immunological assessment.
On the contrary, people primed with an ancestral SARS-CoV-2 strain via vaccination or infection, who contracted an infection with an antigenically drifted variant, showed higher neutralizing antibody titers against Wuhan-Hu-1-like antigen and the new infecting variant.
Belgique Dernières Nouvelles, Belgique Actualités
Similar News:Vous pouvez également lire des articles d'actualité similaires à celui-ci que nous avons collectés auprès d'autres sources d'information.
Novel self-amplifying RNA vaccine confers durable protection against COVID-19, reduces viral shedding in primate studyNovel self-amplifying RNA vaccine confers durable protection against COVID-19, reduces viral shedding in primate study Viral vaccines AntibodyResponse SARSCoV2 Boosterdoses Viralload COVID PLOSPathogens
Lire la suite »
UK live events Covid insurance scheme paid out just once\n\t\t\tKeep abreast of significant corporate, financial and political developments around the world.\n\t\t\tStay informed and spot emerging risks and opportunities with independent global reporting, expert\n\t\t\tcommentary and analysis you can trust.\n\t\t
Lire la suite »
Glasgow landlord given warning over HMO licence breach during Covid lockdownA Glasgow private landlord has been warned after renting out a flat to students despite his HMO licence having lapsed.
Lire la suite »
ALD Mortality by Race Before and During the COVID-19 PandemicThis cross-sectional study examines the national- and state-level age-adjusted mortality rates for alcohol-associated liver disease in 4 racial groups, with a focus on the American Indian or Alaska Native population.
Lire la suite »
Association between prolonged corticosteroids use in COVID-19 and increased mortality in hospitalized patients: a retrospective study with inverse probability of treatment weighting analysis - Critical CareBackground Previous studies have demonstrated a beneficial effect of early use of corticosteroids in patients with COVID-19. This study aimed to compare hospitalized patients with COVID-19 who received short-course corticosteroid treatment with those who received prolonged-course corticosteroid treatment to determine whether prolonged use of corticosteroids improves clinical outcomes, including mortality. Methods This is a retrospective cohort study including adult patients with positive testing for Sars-CoV-2 hospitalized for more than 10 days. Data were obtained from electronic medical records. Patients were divided into two groups, according to the duration of treatment with corticosteroids: a short-course (10 days) and a prolonged-course (longer than 10 days) group. Inverse probability treatment weighting (IPTW) analysis was used to evaluate whether prolonged use of corticosteroids improved outcomes. The primary outcome was in-hospital mortality. Secondary outcomes were hospital infection and the association of different doses of corticosteroids with hospital mortality. Restricted cubic splines were used to assess the nonlinear association between mortality and dose and duration of corticosteroids use. Results We enrolled 1,539 patients with COVID-19. Among them, 1127 received corticosteroids for more than 10 days (prolonged-course group). The in-hospital mortality was higher in patients that received prolonged course corticosteroids (39.5% vs. 26%, p | 0.001). The IPTW revealed that prolonged use of corticosteroids significantly increased mortality [relative risk (RR) = 1.52, 95% confidence interval (95% CI): 1.24–1.89]. In comparison to short course treatment, the cubic spline analysis showed an inverted U-shaped curve for mortality, with the highest risk associated with the prolonged use at 30 days (RR = 1.50, 95% CI 1.21–1.78). Conclusions Prolonged course of treatment with corticosteroids in hospitalized patients with COVID-19 was associated with higher mor
Lire la suite »