B cells are not known to be a major component of the sarcoidosis granuloma, with one exception — lung sections, particularly those from HLA-DRB1*03+ patients with sarcoidosis, show vimentin-rich tertiary lymphoid structures with a corresponding increase in both IgG and IgA antivimentin antibody titers in the blood (85). The gene discussed is HLA-DRB1; the disease is sarcoidosis.