Detection of transcription factors in immune cell populations, particularly in subpopulations that are represented at low frequencies in lymphoid and nonlymphoid organs, presents a particular challenge when using traditional methods such as western blot analysis. Therefore, development of flow cytometry-based methods which allow identification of transcription factors in specific immune cell populations is of main interest. Here we developed and optimized a methodology for rapid and convenient detection of the transcription factor BCL11B in T lymphocyte subpopulations using flow cytometry. The optimal protocol employs saponin and Tween 20 both during the fixation and permeabilization steps, and we demonstrate that it is efficient for three anti-BCL11B antibodies covering distinctive BCL11B epitopes. In addition, we prove that the method preserves the staining of surface markers.
