LTB and systemic lupus erythematosus: Of interest, transcripts for effectors of B cell signaling pathways including FCER2 (CD23), HLA-DQB1, IL 4 receptor, alpha (IL4R) and the protein tyrosine phosphatase, non-receptor type 6 or SHP-1 molecule (PTPN6) were down-regulated in SLE B cells along with lymphotoxin-β (LTB), CD24 and CXCR5.