medwireNews: Findings from a small study suggest that rituximab-treated patients with depleted B cells may be able to mount a T cell-mediated immune response to COVID-19 vaccination, despite having an impaired antibody response.
Daniel Aletaha (Medical University of Vienna, Austria) and team evaluated the humoral and cell-mediated response to the Pfizer–BioNTech (BNT162b2) vaccine in five patients with immune-mediated diseases who had their last rituximab infusion 4–12 months prior to vaccination. They report that three of these people did not have detectable CD19+ B cells and did not develop an antibody response against the SARS-CoV-2 receptor binding domain, whereas two patients had CD19+ B cells and had a positive antibody response, “suggesting the development of a humoral immune response once peripheral B cells are repopulated.”
Despite the diminished humoral immune response in patients with depleted B cells, Aletaha et al say that an interferon-γ response to SARS-CoV-2 peptides, indicating T cell reactivity, was detected in the rituximab-treated patients, irrespective of the antibody response.
These findings suggest that treatment with rituximab “may not have to preclude SARS-CoV-2 vaccination, since a cellular immune response will be mounted even in the absence of circulating B cells,” write the researchers in a letter to the Annals of the Rheumatic Diseases.
They conclude: “It will be important to understand if T cell immunity is important or possibly even sufficient to protect patients against infection with the virus on vaccination.”
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2021 Springer Healthcare Ltd, part of the Springer Nature Group
11 May 2021: The coronavirus pandemic is affecting all healthcare professionals across the globe. Medicine Matters’ focus, in this difficult time, is the dissemination of the latest data to support you in your research and clinical practice, based on the scientific literature. We will update the information we provide on the site, as the data are published. However, please refer to your own professional and governmental guidelines for the latest guidance in your own country.