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Background: Multiple myeloma (MM) patients are at high risk of severe infections including COVID-19 due to an immune dysregulation affecting both innate and adaptive immune responses. However, our understanding of the immune responses to infection and vaccination in MM patients is limited. To gain more detailed insights into infection- and vaccine-elicited T cell immunity in MM, we studied the CD8+ T cell response on the single-epitope level in SARS-CoV-2 convalescent and mRNA-vaccinated MM patients. Methods: We compared peptide/MHC class I tetramer-enriched SARS-CoV-2-specific CD8+ T cells and antibody responses in MM patients (convalescent: n = 16, fully vaccinated: n = 5, vaccinated convalescent: n = 5) and healthy controls (HCs) (convalescent: n = 58, fully vaccinated: n = 7) either after infection with SARS-CoV-2 alone, complete mRNA vaccination or SARS-CoV-2 infection and single-shot mRNA vaccination (hybrid immunity). Results: MM patients have lower frequencies and a lower proportion of fully functional virus-specific CD8+ T cells compared to HCs, after both SARS-CoV-2 infection and vaccination. CD8+ T cell memory subset distribution in MM patients is skewed towards reduced frequencies of central memory (TCM) T cells and higher frequencies of effector memory 1 (TEM1) T cells. In contrast, the humoral immune response was comparable in both cohorts after viral clearance. Notably, CD8+ T cell frequencies as well as the humoral immune response were improved by a single dose of mRNA vaccine in convalescent MM patients. Conclusions: MM patients have relative immunological deficiencies in SARS-CoV-2 immunity but benefit from hybrid immunity. These findings underline the relevance of vaccinations in this vulnerable patient group. [ABSTRACT FROM AUTHOR]

Background and purpose: Acute hepatitis E virus (HEV) infections have been associated with various neurological disorders, including individual cases with Bell's palsy. Nonetheless, systematic studies in the latter are lacking. Therefore, this retrospective study systematically screened a cohort of patients with Bell's palsy for an acute HEV infection. Methods: Overall, 104 patients with Bell's palsy treated in our clinic between 2008 and 2018 were identified. Serum samples were analyzed for anti‐HEV immunoglobulin (Ig)M and IgG antibodies by enzyme‐linked immunosorbent assay. Additionally, serum samples were tested for HEV RNA by polymerase chain reaction in 92 of these 104 patients presenting within the first 7 days from symptom onset. A large group of 263 healthy individuals served as controls. Results: None of the patients with Bell's palsy but two healthy controls (0.8%) had an acute HEV infection. Anti‐HEV IgG seroprevalence indicating previous infection was unexpectedly high in patients with Bell's palsy (34%) and revealed an age‐dependent increase. Conclusions: In this first systematic study, no cases of Bell's palsy in association with an acute HEV infection were identified. However, based on previous case descriptions, rare associations cannot be excluded. Therefore, large prospective multicenter studies will be necessary for conclusions that are more definitive. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 spike mRNA vaccines1–3 mediate protection from severe disease as early as ten days after prime vaccination3, when neutralizing antibodies are hardly detectable4–6. Vaccine-induced CD8+ T cells may therefore be the main mediators of protection at this early stage7,8. The details of their induction, comparison to natural infection, and association with other arms of vaccine-induced immunity remain, however, incompletely understood. Here we show on a single-epitope level that a stable and fully functional CD8+ T cell response is vigorously mobilized one week after prime vaccination with bnt162b2, when circulating CD4+ T cells and neutralizing antibodies are still weakly detectable. Boost vaccination induced a robust expansion that generated highly differentiated effector CD8+ T cells; however, neither the functional capacity nor the memory precursor T cell pool was affected. Compared with natural infection, vaccine-induced early memory T cells exhibited similar functional capacities but a different subset distribution. Our results indicate that CD8+ T cells are important effector cells, are expanded in the early protection window after prime vaccination, precede maturation of other effector arms of vaccine-induced immunity and are stably maintained after boost vaccination.Longitudinal analyses of SARS-CoV-2 mRNA vaccine-elicited epitope-specific CD8+ T cell responses shows that CD8+ T cells are rapidly induced after prime vaccination and stably maintained after boost vaccination. [ABSTRACT FROM AUTHOR]