RT Journal Article SR Electronic T1 Immune response to SARS-CoV-2 vaccination in relation to peripheral immune cell profiles among patients with multiple sclerosis receiving ocrelizumab JF Journal of Neurology, Neurosurgery & Psychiatry JO J Neurol Neurosurg Psychiatry FD BMJ Publishing Group Ltd SP jnnp-2021-328197 DO 10.1136/jnnp-2021-328197 A1 Saskia Räuber A1 Melanie Korsen A1 Niklas Huntemann A1 Leoni Rolfes A1 Thomas Müntefering A1 Vera Dobelmann A1 Alexander M Hermann A1 Tristan Kölsche A1 Karin von Wnuck Lipinski A1 Christina B Schroeter A1 Christopher Nelke A1 Liesa Regner-Nelke A1 Jens Ingwersen A1 Marc Pawlitzki A1 Bianca Teegen A1 Michael Harry Barnett A1 Hans-Peter Hartung A1 Orhan Aktas A1 Philipp Albrecht A1 Bodo Levkau A1 Nico Melzer A1 Tobias Ruck A1 Sven G Meuth A1 David Kremer YR 2022 UL http://jnnp.bmj.com/content/early/2022/02/21/jnnp-2021-328197.abstract AB Background Vaccination has proven to be effective in preventing SARS-CoV-2 transmission and severe disease courses. However, immunocompromised patients have not been included in clinical trials and real-world clinical data point to an attenuated immune response to SARS-CoV-2 vaccines among patients with multiple sclerosis (MS) receiving immunomodulatory therapies.Methods We performed a retrospective study including 59 ocrelizumab (OCR)-treated patients with MS who received SARS-CoV-2 vaccination. Anti-SARS-CoV-2-antibody titres, routine blood parameters and peripheral immune cell profiles were measured prior to the first (baseline) and at a median of 4 weeks after the second vaccine dose (follow-up). Moreover, the SARS-CoV-2-specific T cell response and peripheral B cell subsets were analysed at follow-up. Finally, vaccination-related adverse events were assessed.Results After vaccination, we found anti-SARS-CoV-2(S) antibodies in 27.1% and a SARS-CoV-2-specific T cell response in 92.7% of MS cases. T cell-mediated interferon (IFN)-γ release was more pronounced in patients without anti-SARS-CoV-2(S) antibodies. Antibody titres positively correlated with peripheral B cell counts, time since last infusion and total IgM levels. They negatively correlated with the number of previous infusion cycles. Peripheral plasma cells were increased in antibody-positive patients. A positive correlation between T cell response and peripheral lymphocyte counts was observed. Moreover, IFN-γ release was negatively correlated with the time since the last infusion.Conclusion In OCR-treated patients with MS, the humoral immune response to SARS-CoV-2 vaccination is attenuated while the T cell response is preserved. However, it is still unclear whether T or B cell-mediated immunity is required for effective clinical protection. Nonetheless, given the long-lasting clinical effects of OCR, monitoring of peripheral B cell counts could facilitate individualised treatment regimens and might be used to identify the optimal time to vaccinate.Data are available upon reasonable request. Further information and requests for resources and anonymised clinical data should be directed to and will be fulfilled by David Kremer (DavidMaxJoe.Kremer@med.uni-duesseldorf.de)