text: LMP1 Upregulates IL10 Expression and Constitutively Activates Stat3
  (A) Relative expression of IL10, IL15, and IFNgamma mRNA in WT and LMP1 transgenic B cells (CD19+), as detected with an Rnase protection assay. Mouse lymphoma cell lines 967 and K46mu were used as controls. Expression levels were quantified with a phosphorimager and values were normalized to the ribosomal housekeeping gene L32. The cytokine:L32 ratio was set to 1 in the mouse B cell lymphoma line 967. 
  (B and C) Immunoblot analysis of activated pStat3 in purified B cells (CD19+) from WT and LMP1 transgenic mice (B) at the time of harvest, and (C) 4 h after culture with or without IL10, a neutralizing antibody to IL10, or a rat IgG1 isotype control. (C) Shown are the results for WT lymphoma 1 and LMP1 transgenic lymphoma 1. Arrows indicate the positions of the alpha and beta isoforms of Stat3. Actin was used as a loading control. 
  (D) Immunohistochemistry detection of activated nuclear pStat3 in the spleens of WT and LMP1 transgenic mice. Scale bar, 20 mum. 
  