You can find answers in these articles....

http://www.ncbi.nlm.nih.gov/pubmed/24797503

http://www.ncbi.nlm.nih.gov/pubmed/23962745

http://www.ncbi.nlm.nih.gov/pubmed/23904441

Good  Luck

please see this article :

http://www.ncbi.nlm.nih.gov/pubmed/16670296

I guess that it might be play imortant role in naiive B or memory B cells. 

  Its role in mediating pro- and anti-inflammatory effects, IL-27 promotes CD4+ T cell differentiation to the Th1 lineage by inducing expression of the transcription factor T-bet and up regulating IL-12Rβ2., IL-27 suppresses Th2 and Th17 differentiation and proliferation.  Binding to the IL-27R, which is expressed most abundantly on activated T cells and NK cells with lower expression on B cells and naïve T-cells, leads to the phosphorylation and activation of the JAK/STAT pathway, with STAT1 and STAT3 as the predominant factors mediating the effects of IL-27.

thank you Dear Juan Otaso Sir for your valuable answer

You are wellcome