Humoral and cellular responses to SARS-CoV-2 in convalescent COVID-19 patients with multiple sclerosis

ABSTRACT

Introduction: Information about how SARS-CoV-2 specific humoral and cellular response is modified by disease-modifying therapies (DMTs) is scarce. Objective: To investigate humoral and cellular responses to SARS-CoV-2 and factors for presenting them in a Barcelona cohort of pwMS. Methods: Retrospective cohort study of adult unvaccinated PwMS with confirmed COVID-19 with at least one SARS-CoV-2 antibody (Ab) determination included from February 2020 to May 2021 and followed until May 2021. Demographic, clinical and laboratory data were obtained. Humoral SARS-CoV-2 response was measured with commercial chemiluminescence immunoassays targeting specific Ab against spike (IgG-S) and nucleocapsid proteins (Ig-N), as per clinical practice. SARS-CoV-2 specific T-cell response was studied in 42 selected pwMS according to DMT by a whole blood Interferon-Gamma (IFN-y) Release Immunoassay. Humoral and cellular response was assesed using a logistic regression model corrected for age, sex, comorbidities, MS form, expanded disability status scale, DMT, COVID-19 severity and PCR result. Results: 145 pwMS were enrolled (mean age 46.8 years;64.1% female;18.6% progressive forms, 20.7% untreated, 22.8% on anti-CD20s therapies and 56.6% on other DMTs). Humoral and cellular tests were performed from 0.3 to 13.1 months after COVID-19. 121(83.5%) presented positive Ab (57.6% anti-CD20 therapy, 90.2% other DMTs, 93.3% untreated). Untreated patients presented higher Ig-N titres (34.3[128.8]) compared to those with anti-CD20s (0.08[0.13], p<0.01), and other DMTs (19.55[42.92], p<0.01). Humoral response persisted over 6 months in 12/12 untreated, 9/22 with anti-CD20s and 22/28 with other DMTs (p=0.068). 31/42(73.8%) presented cellular response (81.0% anti- CD20, 62.5% other DMTs, 80.0% untreated), with similar levels of IFN-y levels among DMTs. 5/12(41.7%) anti-CD20-treated PwMS with negative Ab presented cellular response. In the multivariate analysis, humoral response decreased in anti-CD20 therapy (OR 0.08[95% CI,0.01-0.55]) and was associated with male sex (OR 3.59[1.02-12.68]). Cellular response was associated with seropositivity (OR13.0[1.29-130.4]), but can be present even in the absence of Ab. Conclusions: Humoral response is altered by DMTs, specially in anti-CD20-treated PwMS. Cellular response is associated with seropositivity but can be present in anti-CD20-treated PwMS even in the absence of Ab. Both can be detected up to 13.1 months after COVID-19.