I isolate naive OTII CD4+ T cells(CD45.2) and transfer these cells into B6 mice (CD45.1), The next day, I give 10 ug OVA peptide(control group gives PBS) by i.v. injection. 5 days after antigen injection, I sacrifice mice and analyze the cells I transfer into mice, but the percentage of Treg (in lymph node, spleen and mesenteric lymph node) in experiment and control group have no difference. And I don't know the reason of failure. Can anyone help me with this problem?
But in steady state, when antigen is injected into mice, it will let antigen-specific cells anergy or differentiate into Treg cells. And I characterize CD45.2+FOXP3+ as OT II Tregs.
you could activate Aryl hydrocarbon receptor with non-toxic ligands to stimulate Treg differentiation.
@Christoph Vogel
Can you explain in detail about why we can use non-toxic ligands to activate Aryl hydrocarbon receptor to stimulate Treg differentiation?
@Dominic R Beal
I think when we induce Treg cells, we can't use adjuvant to activate. Because it will biases the immune response to Th1 or Th2.
There is a lot of literature in Pubmed. Please use AhR and Treg as key words and you'll find a lot of helpful information. There are many different ligands for AhR. You could try beta-naphtoflavone. Be careful since one ligand (FICZ a UV product of tryptophan) has been reported to induce Th17.