IFI6 and systemic lupus erythematosus: It should be noted that no interferon inducible genes were identified as differentially expressed between tonsil PC versus PB and either tonsil PC or tonsil PB versus SLE PC.G1P3 alone was found to be differentially upregulated in tonsil PC compared with tonsil non-IgSC, demonstrating that normal IgSC do not possess an IFN inducible signature.