Two studies on the physical response of patients with rheumatic diseases to vaccination against SARS-CoV-2 are featured in the January issue of Arthritis & Rheumatology.
First, B cell depletion is an established therapeutic principle in a wide range of autoimmune diseases. However, B cells are also critical for inducing protective immunity after infection and vaccination. Thus, Simon et al. undertook a study to assess humoral and cellular immune responses after infection with, or vaccination against, SARS-CoV-2 in patients with B cell depletion and controls who are B cell competent.
In the second study, Connolly et al. evaluated disease flare and post-vaccination reactions (reactogenicity) in patients with rheumatic and musculoskeletal diseases (RMDs) following two-dose SARS-CoV-2 messenger RNA (mRNA) vaccination.
The Studies
Simon et al. assessed antibody responses (tested using enzyme-linked immunosorbent assay) and T cell responses (tested using interferon-γ enzyme-linked immunospot assay) against the SARS-CoV-2 spike S1 and nucleocapsid proteins in a limited number of previously infected (n=6) and vaccinated (n=8) patients with autoimmune diseases and B cell depletion, as well as previously infected (n=30) and vaccinated (n=30) healthy controls.
The researchers observed B cell and T cell responses to the nucleocapsid protein only after infection; however, B cell and T cell responses to spike S1 were found after both infection and vaccination. Vaccination induced a SARS-CoV-2 antibody response in all vaccinated controls (30 of 30 [100%]), but in none of the vaccinated patients with B cell depletion (0 of 8). In contrast, after SARS-CoV-2 infection, both the patients with B cell depletion and healthy controls developed antibodies. T cell responses against the spike S1 and nucleocapsid proteins were found in both infected and vaccinated patients with B cell depletion, as well as in the control group.
These data show that B cell depletion completely blocks humoral but not T cell SARS-CoV-2 vaccination response. Further, limited humoral immune responses are found after SARS-CoV-2 infection in patients with B cell depletion.
Connolly et al. studied patients with rheumatic and musculoskeletal diseases (RMD) who received a two-dose SARS-CoV-2 mRNA vaccination between December 2020 and April 2021. The patients (n=1,377) completed questionnaires detailing local and systemic reactions experienced within seven days of each vaccine dose (dose 1 and dose 2), and one month after dose 2, detailing any flares of their RMD. Associations between demographic/clinical characteristics and flares requiring treatment were evaluated using modified Poisson regression.
Among the patients, 11% reported flares requiring treatment; there were no reports of severe flares. Flares were associated with prior SARS-CoV-2 infection (relative risk [RR] 2.09, P=0.02), flares in the six months preceding vaccination (RR 2.36, P<0.001), and the use of combination immunomodulatory therapy (RR 1.95, P<0.001). The most frequently reported local and systemic reactions included injection site pain (87% after dose 1, 86% after dose 2) and fatigue (60% after dose 1, 80% after dose 2). Reactogenicity increased after dose 2, particularly for systemic reactions. No allergic reactions or SARS-CoV-2 diagnoses were reported.
