Innate immune cell activation by adjuvant AS01 in human lymph node explants is age independent.

Vaccine adjuvants are thought to work by stimulating innate immunity in the draining lymph node (LN), although this has not been proven in humans. To bridge the data obtained in animals to humans, we have developed an in situ human LN explant model to investigate how adjuvants initiate immunity. Slices of explanted LNs were exposed to vaccine adjuvants and revealed responses that were not detectable in LN cell suspensions.

Functional and epigenetic changes in monocytes from adults immunized with an AS01-adjuvanted vaccine.

The adjuvant AS01 plays a key role in the immunogenicity of several approved human vaccines with demonstrated high efficacy. Its adjuvant effect relies on activation of the innate immune system. However, specific effects of AS01-adjuvanted vaccines on innate cell function and epigenetic remodeling, as described for Bacille Calmette-Guérin (BCG) and influenza vaccines, are still unknown.

Rituximab-to-vaccine interval on SARS-CoV-2 immunogenicity in children: The potential role of prior natural infection.

Background: Treatment with anti-CD20 antibodies (rituximab) is used in both adults and children to treat various autoimmune and oncological diseases. Rituximab depletes B CD20+ cells and, thereby, antibody response to vaccines. This study aimed to examine the antibody response to mRNA-based COVID-19 vaccines in children aged 5-18 years undergoing rituximab treatment compared to healthy matched children.

Immune response to the recombinant herpes zoster vaccine in people living with HIV over 50 years of age compared to non-HIV age-/gender-matched controls (SHINGR'HIV): a multicenter, international, non-randomized clinical trial study protocol.

Background: The burden of herpes zoster (shingles) virus and associated complications, such as post-herpetic neuralgia, is higher in older adults and has a significant impact on quality of life. The incidence of herpes zoster and post-herpetic neuralgia is increased in people living with HIV (PLWH) compared to an age-matched general population, including PLWH on long-term antiretroviral therapy (ART) with no detectable viremia and normal CD4 counts. PLWH - even on effective ART may- exhibit sustained immune dysfunction, as well as defects in cells involved in the response to vaccines.

Refined innate plasma signature after rVSVΔG-ZEBOV-GP immunization is shared among adult cohorts in Europe and North America.

Background: During the last decade Ebola virus has caused several outbreaks in Africa. The recombinant vesicular stomatitis virus-vectored Zaire Ebola (rVSVΔG-ZEBOV-GP) vaccine has proved safe and immunogenic but is reactogenic. We previously identified the first innate plasma signature response after vaccination in Geneva as composed of five monocyte-related biomarkers peaking at day 1 post-immunization that correlates with adverse events, biological outcomes (haematological changes and viremia) and antibody titers.

State-of-the-Science of human papillomavirus vaccination in women with human immunodeficiency Virus: Summary of a scientific workshop.

The burden of cervical cancer is disproportionately distributed globally, with the vast majority of cases occurring in low- and middle-income countries. Women with human immunodeficiency virus (HIV) (WWH) are at increased risk of human papillomavirus (HPV) infection and cervical cancer as compared to HIV-negative individuals. HPV vaccination remains a priority in regions with a high burden of cervical cancer and high HIV prevalence.

C-type lectin receptor agonists elicit functional IL21-expressing Tfh cells and induce primary B cell responses in neonates.

Introduction: C-type lectin receptor (CLR) agonists emerged as superior inducers of primary B cell responses in early life compared with Toll-like receptor (TLR) agonists, while both types of adjuvants are potent in adults.

Methods: Here, we explored the mechanisms accounting for the differences in neonatal adjuvanticity between a CLR-based (CAF01) and a TLR4-based (GLA-SE) adjuvant administered with influenza hemagglutinin (HA) in neonatal mice, by using transcriptomics and systems biology analyses.

Results: On day 7 after immunization, HA/CAF01 increased IL6 and IL21 levels in the draining lymph nodes, while HA/GLA-SE increased IL10.

Antibody response in children with multisystem inflammatory syndrome related to COVID-19 (MIS-C) compared to children with uncomplicated COVID-19.

Objectives: To comprehensively analyze the quality of the antibody response between children with Multisystem inflammatory syndrome (MIS-C) and age-matched controls at one month after SARS-CoV-2 exposure, and infected in the same time-period.

Methods: Serum from 20 MIS-C children at admission, and 14 control children were analyzed. Antigen specific antibody isotypes and subclasses directed against various antigens of SARS-CoV-2 as well as against human common coronavirus (HCoVs) and commensal or pathogenic microorganisms were assessed by a bead-based multiplexed serological assay and by ELISA.

Systems serology-based comparison of antibody effector functions induced by adjuvanted vaccines to guide vaccine design.

The mechanisms by which antibodies confer protection vary across vaccines, ranging from simple neutralization to functions requiring innate immune recruitment via Fc-dependent mechanisms. The role of adjuvants in shaping the maturation of antibody-effector functions remains under investigated. Using systems serology, we compared adjuvants in licensed vaccines (AS01/AS01/AS03/AS04/Alum) combined with a model antigen.

Systems analysis of human responses to an aluminium hydroxide-adsorbed TLR7 agonist (AS37) adjuvanted vaccine reveals a dose-dependent and specific activation of the interferon-mediated antiviral response.

The candidate Adjuvant System AS37 contains a synthetic toll-like receptor agonist (TLR7a) adsorbed to alum. In a phase I study (NCT02639351), healthy adults were randomised to receive one dose of licensed alum-adjuvanted meningococcal serogroup C (MenC-CRM) conjugate vaccine (control) or MenC-CRM conjugate vaccine adjuvanted with AS37 (TLR7a dose 12.5, 25, 50 or 100 µg).

Neutralization capacity of antibodies elicited through homologous or heterologous infection or vaccination against SARS-CoV-2 VOCs.

Emerging SARS-CoV-2 variants raise questions about escape from previous immunity. As the population immunity to SARS-CoV-2 has become more complex due to prior infections with different variants, vaccinations or the combination of both, understanding the antigenic relationship between variants is needed. Here, we have assessed neutralizing capacity of 120 blood specimens from convalescent individuals infected with ancestral SARS-CoV-2, Alpha, Beta, Gamma or Delta, double vaccinated individuals and patients after breakthrough infections with Delta or Omicron-BA.

Fitness of B-Cell Responses to SARS-CoV-2 WT and Variants Up to One Year After Mild COVID-19 - A Comprehensive Analysis.

Objective: To comprehensively evaluate SARS-CoV-2 specific B-cell and antibody responses up to one year after mild COVID-19.

Methods: In 31 mildly symptomatic COVID-19 participants SARS-CoV-2-specific plasmablasts and antigen-specific memory B cells were measured by ELISpot. Binding antibodies directed against the proteins spike (S), domain S1, and nucleocapsid (N) were estimated using rIFA, ELISA, and commercially available assays, and avidity measured using thiocyanate washout.

Utility of urinary cytokine levels as predictors of the immunogenicity and reactogenicity of AS01-adjuvanted hepatitis B vaccine in healthy adults.

Plasma cytokines are useful indicators of the inflammatory response to vaccination, and can serve as potential biomarkers of the systemic reactogenicity and immunogenicity of vaccines. Measurement of cytokines in urine may represent a non-invasive alternative to the blood-based markers. To evaluate whether urinary cytokine levels can help predict vaccine responses to an AS01-adjuvanted vaccine, we measured concentrations of 24 cytokines in the urine from 30 hepatitis B virus (HBV)-naïve adults following administration of AS01-adjuvanted HBV surface antigen vaccine (NCT01777295).

Omicron-Specific Cytotoxic T-Cell Responses After a Third Dose of mRNA COVID-19 Vaccine Among Patients With Multiple Sclerosis Treated With Ocrelizumab.

Importance: The SARS-CoV-2 variant B.1.1.

Robust T-Cell Responses in Anti-CD20-Treated Patients Following COVID-19 Vaccination: A Prospective Cohort Study.

Background: Patients treated with anti-CD20 therapy are particularly at risk of developing severe coronavirus disease 2019 (COVID-19); however, little is known regarding COVID-19 vaccine effectiveness in this population.

Methods: This prospective observational cohort study assesses humoral and T-cell responses after vaccination with 2 doses of mRNA-based COVID-19 vaccines in patients treated with rituximab for rheumatic diseases or ocrelizumab for multiple sclerosis (n = 37), compared to immunocompetent individuals (n = 22).

Results: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibodies were detectable in only 69.

Association Between Immunogenicity and Reactogenicity: A Post Hoc Analysis of 2 Phase 3 Studies With the Adjuvanted Recombinant Zoster Vaccine.

A recurrent question is whether transient reactions to vaccines translate into better immune responses. Using clinical data from 2 large phase 3 studies of the recombinant zoster vaccine, we observed a small but statistically significant association between the intensity of a frequent side effect (pain) after vaccination and immune responses to vaccination. However, despite the statistical correlation, the impact on the immune response is so small, and the immune response in individuals without pain already sufficient, that pain cannot be a surrogate marker for an appropriate immune response.

Robust innate responses to SARS-CoV-2 in children resolve faster than in adults without compromising adaptive immunity.

SARS-CoV-2 infection in children is less severe than it is in adults. We perform a longitudinal analysis of the early innate responses in children and adults with mild infection within household clusters. Children display fewer symptoms than adults do, despite similar initial viral load, and mount a robust anti-viral immune signature typical of the SARS-CoV-2 infection and characterized by early interferon gene responses; increases in cytokines, such as CXCL10 and GM-CSF; and changes in blood cell numbers.

Longitudinal Analysis of Inflammatory Response to SARS-CoV-2 in the Upper Respiratory Tract Reveals an Association with Viral Load, Independent of Symptoms.

Background: SARS-CoV-2 infection leads to high viral loads in the upper respiratory tract that may be determinant in virus dissemination. The extent of intranasal antiviral response in relation to symptoms is unknown. Understanding how local innate responses control virus is key in the development of therapeutic approaches.

Pediatric COVID-19: Immunopathogenesis, Transmission and Prevention.

Children are unique in the context of the COVID-19 pandemic. Overall, SARS-CoV-2 has a lower medical impact in children as compared to adults. A higher proportion of children than adults remain asymptomatic following SARS-CoV-2 infection and severe disease and death are also less common.