SARS-CoV-2 spike antibody and T cell response in MS patients on high efficacy therapies post vaccine

There is limited knowledge about SARS-CoV-2 spike antibody and long-term T cell responses in multiple sclerosis (MS) patients on high efficacy treatments post SARS-CoV-2 vaccine.

To assess spike antibody and T cell responses in MS patients on fingolimod (FIN), ocrelizumab (OCR) and healthy controls (HC) post vaccine.

We studied spike antibody seroconversion rates and T cell responses by flow cytometry in HC and MS patients.

The seroconversion rate in FIN patients after 2-vax at 2-3 m 6/8 (75 %), 5-6 m 9/9 (100 %) and after 3 vax at 2-3 m 12/12 (100 %), 5-6 m 16/19 (84.21 %) and 8-12 m 5/5 (100 %). The seroconversion rate in OCR patients after 2-vax at 2-3 m 8/29 (27.6 %), 5-6 m 3/16 (18.8 %), 8-12 m 1/3 (33.3 %) and after 3 vax at 2-3 m 12/12 (100 %), 5-6 m 10/21 (47.6 %) and 8-12 m 7/12 (58.33 %). HC show a 100 % seroconversion rate. HC and OCR patients preserve both the percentage and absolute number of CD4+ T cells. FIN patients have a profound CD4+ T cell loss but compensatory rise in CD8+ T cell percentages. FIN patients exhibit the highest percentage of IFNγ+ CD4+ T cells and IFNγ+/TNFα+ CD8+ T cells.

Healthy controls show the highest spike antibody seroconversion rate while ocrelizumab treated patients remain low even after a third dose despite preserved CD4+ counts, whereas fingolimod treated patients lose CD4+ T cells but compensate with inflated CD8+ frequencies and a cytokine rich effector T cell profile.