Objectives Immunogenicity to the SARS-CoV-2 mRNA vaccines in adolescents and young adults (AYA) with childhood-onset rheumatic diseases (cRD) is unknown. We aimed to evaluate the humoral immunogenicity and safety of the vaccines in our AYA with cRD. Methods A monocentric observational study with 159 AYA (50.3% female and 70.4% Chinese). Humoral immunogenicity was assessed at 2–3 and 4–6 weeks following first and second vaccination by cPass™ SARS-CoV-2 Neutralisation Antibody Assay. Inhibition signal of ≥ 30% defined the cut-off for positive detection of the SARS-CoV-2 neutralising antibodies. Vaccine safety and disease activity were assessed within 6 weeks after second vaccination. Results 64.9% and 99.1% of 159 patients (median age 16.9-year-old, IQR : 14.7–19.5) mounted positive SARS-CoV-2 neutralising responses after first and second vaccination, respectively. Most patients (89.8%) had ≥90% inhibition signal after second vaccination. Methotrexate and mycophenolate mofetil increased the risk associated with negative cPass neutralisation responses following the first vaccination. Holding both medications after each vaccination did not affect immunogenicity. There was no symptomatic COVID-19 infection. Local reaction remained the most common (23.3–25.2%) adverse event, without serious complication. Two and seven patients flared following the first and second vaccination, respectively. Subgroup analyses of the 12–18-year-old cohort did not show any differences in vaccine efficacy, predictors of poor response and general safety, but higher proportion of disease flares. Conclusions SARS-CoV-2 mRNA vaccines were efficacious after the two-dose regimen in almost all AYA with cRD without serious adverse event. The rate of disease flare observed is 4.4% after the second mRNA vaccine dose.

Juvenile spondyloarthritis (JSpA) refers to a diverse spectrum of immune-mediated inflammatory arthritides whose onset occurs in late childhood and adolescence. Like its adult counterpart, JSpA is typified by a strong association with human leukocyte antigen-B27 (HLA-B27) and potential axial involvement, while lacking rheumatoid factor (RF) and distinguishing autoantibodies. A characteristic manifestation of JSpA is enthesitis (inflammation of insertion sites of tendons, ligaments, joint capsules or fascia to bone), which is commonly accompanied by bone resorption and new bone formation at affected sites. In this Review, advances in the role of HLA-B27, enthesitis and its associated osteoproliferation in JSpA pathophysiology and treatment options will be discussed. A deeper appreciation of how these elements contribute to the JSpA disease mechanism will better inform diagnosis, prognosis and therapy, which in turn translates to an improved quality of life for patients.

An accurate depiction of the convalescent COVID-19 immunome will help delineate the immunological milieu crucial for disease resolution and protection. Using mass cytometry, we characterized the immune architecture in patients recovering from mild COVID-19. We identified a virus-specific immune rheostat composed of an effector T (Teff) cell recall response that is balanced by the enrichment of a highly specialized regulatory T (Treg) cell subset. Both components were reactive against a peptide pool covering the receptor binding domain (RBD) of the SARS-CoV-2 spike glycoprotein. We also observed expansion of IFNγ+ memory CD4+ T cells and virus-specific follicular helper T (TFH) cells. Overall, these findings pinpoint critical immune effector and regulatory mechanisms essential for a potent, yet harmless resolution of COVID-19 infection.