The following is a summary of “Recall vaccination increases detectable B-cell reactivity in persons with multiple sclerosis treated with ocrelizumab,” published in the April 2025 issue of Journal of Neurology by Moiola et al. 

Repeated anti-SARS-CoV-2 vaccination in persons with MS (pwMS) on ocrelizumab raises concerns about immune response variability. 

Researchers conducted a retrospective study to investigate antiviral antibody and T-cell responses following mRNA vaccination for SARS-CoV-2 in ocrelizumab-treated persons with multiple sclerosis. 

They stimulated peripheral blood mononuclear cells with SARS-CoV-2 peptide pools and assessed T-cell reactivity using ELISPOT for IFN-γ detection and multiparametric flow cytometry for T-cell activation. Anti-SARS-CoV-2 spike and nucleocapsid antibodies in plasma were analyzed using 2 commercial platforms. 

The results showed that the ELISPOT assay against the SARS-CoV-2 spike protein revealed robust T-cell reactivity following mRNA vaccination, sustained through repeated cycles but declining 2 years after the last boost. Flow cytometry confirmed the presence of CD8⁺ T memory stem cells, which increased after repeated boosts, similar to anti-SARS-CoV-2 antibodies. 

Investigators found that repeated vaccination cycles increased T and B-cell reactivity against SARS-CoV-2. The immune response strengthened with each boost. 

Source: link.springer.com/article/10.1007/s00415-025-13027-x