Association of the CD28 markers with the disease activity in systemic lupus erythematosus patients

Background: Systemic Lupus Erythematosus (SLE) is a complex autoimmune disease with diverse manifestations and unpredictable activity. CD28 markers, particularly sCD28, is a promising biomarker for evaluating SLE disease activity. This study aimed to investigate the significance of CD28 markers in evaluating disease activity in SLE and the role of sCD28 in various clinical manifestations. Methods: A total of 40 female subjects, aged between 18 and 45 years, who fulfilled the 2019 EULAR/ACR classification criteria for SLE were recruited in this study. Twenty healthy matched individuals were also recruited as control. Comprehensive data on demographic information, clinical manifestations, laboratory test findings, and treatment history were collected from all participants. The Indonesian version of SLEDAI-2K score was utilized to assess disease activity, categorizing patients into active SLE and lupus low disease activity (LLDAS). Collected data were analyzed on SPSS for Windows version 25.0. Results: Patients with SLE in LLDAS category had significantly lower SLEDAI scores (1.8 ± 1.4 vs 11.7 ± 4.9, p<0.001) with mild clinical manifestation. Active SLE patients had the lowest percentages of CD4 ⁺CD28 ⁺ cells (5.7 ± 4.1%) and the highest sCD28 concentration (26.2 ± 11.3 ng/ml) compared to other groups. Moreover, sCD28 concentration demonstrated a moderate positive correlation with SLE disease activity. In most cases, higher sCD28 concentrations were associated with clinical manifestations, particularly in neuropsychiatric lupus (OR 7.1 [1.8 - 67.9], p=0.047), nephritis (OR 14.5 [1.6 - 131.9], p=0.017), and mucocutaneous manifestations (OR 3.4 [1.9 - 12.8], p=0.035). Conclusions: Our study establishes the link between CD28 markers and disease activity, including certain clinical manifestations in SLE. We suggest that CD28 has a potential role in predicting disease activity. However, further research through longitudinal studies is required to strengthen these findings.