Firstly, we aimed to compare the yield of detectable SmD1p-specific CD4+ T cells obtained by conventional intracellular staining for the Th1 lineage cytokine IFN-γ, the most abundant pro-inflammatory CD4+ T cell cytokine in murine lupus (11, 19), with intracellular staining for CD154. Here, CD4 is linked to systemic lupus erythematosus.