Christiane Eberhardt

Christiane Sigrid Eberhardt is a physician-scientist with a background in vaccine-immunology and is currently working as clinical vaccinologist at the Center for Vaccinology in Geneva. She completed her MD at the University Aachen, Germany, followed by a residency in pediatrics and a fellowship in neonatology at the University Hospitals of Geneva, Switzerland and a fellowship training at Great Ormond Street Hospital in London, UK. She received a Master’s degree with distinctions in Immunology of Infectious Diseases from the London School of Hygiene and Tropical Medicine, UK. Dr Eberhardt gained extensive experiences in vaccine immunology as research fellow under Prof. Claire-Anne Siegrist at the Center for Vaccinology, Geneva, and as postdoctoral research fellow in Prof. Rafi Ahmed’s laboratory at the Emory Vaccine Center, Atlanta, US, where she focused her work on the understanding of human B cell and CD8 T cell immunology in the context of vaccination and viral infections. She conducted a policy-changing clinical study on the timing of maternal pertussis immunization, a work that was awarded with several prizes. She was supported for her training by private foundations and the Swiss National Science Foundation and currently holds two privately funded research grants to assess the ontogeny of B cell responses in early life.

PRESENTATION SUMMARY

Role of T cells in COVID-19 vaccination and beyond

During the COVID-19 pandemic, mRNA vaccines were rapidly employed to decrease mortality and morbidity in a population immunologically naïve to SARS-CoV-2 and thus particularly susceptible. It has become clear that T cells play a role in the protection against severe disease, and that T-cell mediated memory responses are less susceptible to SARS-CoV-2 mutations compared to neutralizing antibody responses. Particularly in patients treated with B-cell depleting agents, such as monoclonal anti-CD20 antibodies, SARS-CoV-2-specific antibody titers remain undetectable or low after two or even three doses of mRNA vaccines. Anti-CD20 treatment also affects antigen-presentation to T cells. However, we and others have shown that in anti-CD20-treated adult patients with multiple sclerosis (MS) or rheumatoid diseases (RD), two doses of COVID-19 mRNA vaccines induce robust and functional T-cell responses against the vaccine-strain virus similar to those of immunocompetent individuals. These T-cell responses are enhanced after a third dose and recognize both the vaccine-strain and the Delta and Omicron variants. Vaccine-strain specific memory T cells remained detectable 6 months after the second dose and could therefore be quickly reactivated by exposure into potent effector cells. This talk discusses T cell responses following COVID-19 vaccination and opens perspectives for further research.

Haut