Project description:RNA was extracted from whole blood of subjects collected in Tempus tubes prior to COVID-19 mRNA booster vaccination. D01 and D21 correspond to samples collected at pre-dose 1 and pre-dose 2 respectively. RNA was also extracted from blood collected at indicated time points post-vaccination. DB1, DB2, DB4 and DB7 correspond to booster day 1 (pre-booster), booster day 2, booster day 4 and booster day 7 respectively. The case subject experienced cardiac complication following mRNA booster vaccination. We performed gene expression analysis of case versus controls over time.
Project description:Vaccination triggers the production of antigen-specific antibodies, including IgG. IgG molecules are glycosylated at the Fc region, and these glycan modifications markedly influence Fc receptor binding and downstream immune functions. Notably, infections with enveloped viruses such as SARS-CoV-2 can trigger the production of afucosylated IgG, which enhances FcγRIIIa binding and promotes antibody-dependent cellular cytotoxicity. Despite its importance, the glycosylation profiles of antigen-specific IgG following vaccination remain understudied, particularly in animal models. In this study, we investigated the Fc glycosylation patterns of antigen-specific IgG in hamsters and rhesus macaques following immunization with the Ad26.COV2.S COVID-19 vaccine. Overall, our findings demonstrate that IgG Fc glycosylation dynamics in these animal models largely parallel those in humans. For example, we observed a transient afucosylated IgG response in both species, resembling the response previously reported in humans. These results indicate that IgG Fc glycosylation responses to vaccination in macaques and hamsters recapitulate key features of the human response, supporting their use as translational models for adenovirus vector-based vaccination studies.
Project description:COVID-19, caused by SARS-CoV-2, is a virulent pneumonia, with >4,000,000 confirmed cases worldwide and >280,000 deaths as of May 13, 2020. It is critical to develop and evaluate vaccines and therapeutic interventions as rapidly as possible. Mice, the ideal animal for such studies, are resistant to SARS-CoV-2. Here, we overcome this difficulty by exogenous delivery of human ACE2 with a replication-deficient adenovirus (Ad5-hACE2). Ad5-hACE2-sensitized mice developed pneumonia characterized by weight loss, severe pulmonary pathology, and high-titer virus replication in lungs. Type I interferon, T cells and, most importantly, signal transducer and activator of transcription 1 (STAT1) are critical for virus clearance and diminished disease in these mice. Ad5-hACE2-transduced mice enabled rapid assessments of a vaccine candidate, of human convalescent plasma, and of two antiviral therapies (poly I:C and remdesivir). In summary, we describe a murine model of broad and immediate utility to investigate COVID-19 pathogenesis, and to evaluate new therapies and vaccines.
Project description:Acute viral infections can have durable functional impacts on the immune system long after recovery, but how they affect homeostatic immune states and responses to future perturbations remain poorly understood. Here we use systems immunology approaches, including longitudinal multimodal single cell analysis (surface proteins, transcriptome, and V(D)J sequences), to comparatively assess baseline immune statuses and responses to influenza vaccination in 33 healthy individuals after recovery from mild, non-hospitalized COVID-19 (mean: 151 days after diagnosis) and 40 age- and sex-matched controls who never had COVID-19. At baseline and independent of time since COVID-19, recoverees had elevated T-cell activation signatures and lower expression of innate immune genes in monocytes. COVID-19-recovered males had coordinately higher innate, influenza-specific plasmablast, and antibody responses after vaccination compared to healthy male and COVID-19-recovered females, partly because male recoverees had monocytes with higher IL-15 responses early after vaccination coupled with elevated pre-vaccination frequencies of "virtual memory" like CD8+ T-cells poised to produce more IFNg upon IL-15 stimulation. In addition, the expression of the repressed innate immune genes in monocytes increased by day 1 through day 28 post-vaccination in recoverees, thus moving towards the pre-vaccination baseline of healthy controls. In contrast, these genes decreased on day 1 and returned to the baseline by day 28 in controls. Our study reveals sex-dimorphic impacts of prior mild COVID-19 and suggests that viral infections in humans can establish new immunological set-points impacting future immune responses in an antigen-agnostic manner.
Project description:At this stage in the COVID-19 pandemic, most infections are 'breakthrough' infections that occur in individuals with prior immunity to SARS-CoV-2 through infection or vaccination. Understanding both innate and adaptive immune induction in the setting of breakthrough infection is critical to refining vaccine strategies to ensure long-term efficacy against emerging variants, yet existing studies have primarily focused on adaptive immune responses. Here, we performed single-cell transcriptomic, proteomic, and functional profiling of innate and adaptive immunity during primary and breakthrough COVID-19 infections by comparing immune responses between unvaccinated and vaccinated individuals during the SARS-CoV-2 Delta wave. Breakthrough infections were characterized by a significantly less activated transcriptomic profile in CD56dim NK cells and monocytes, with induction of pathways limiting NK cell proliferation and monocyte migratory potential. Furthermore, we observed a female-specific trend of increased transcriptomic activation of CD16+ monocytes and type-2 conventional dendritic cells (cDC2s) during breakthrough infections. Despite these differences, antibody-dependent cellular cytotoxicity responses were similar between breakthrough and primary infection groups. These insights suggest that prior vaccination prevents overactivation of innate immune responses during breakthrough infections with discernible sex-specific patterns and underscore the potential of harnessing vaccines in mitigating pathologic immune responses resulting from overactivation.