A strong statistically significant difference in FLC concentrations was still observed between SLE patients and healthy controls after adjusting for total IgG, total IgA or total IgM concentrations, respectively (p<0.0001, regarding total FLC and λFLC and κFLC, individually, when adjusting for either total IgG, total IgA or total IgM, respectively), which was also expected as serum Ig levels were found to be similar between the two groups (Table 1). Here, CD40LG is linked to systemic lupus erythematosus.