Objective: CD4+ helper T lymphocytes and gamma delta T cells play important role in antimicrobial immunity, however, the mechanism of interactions in question still remains to be elucidated.
Methods: CD4+ T cells and gamma delta T cells separated from peripheral blood lymphocytes of healthy donors by panning technique were stimulated with intracellular pathogen-Mycobacterium tuberculosis and human herpes virus-6 as well as extracellular pathogen-Trichomonas Vaginalis respectively in vitro.
Results: The stimuli induced CD4+ T cells significantly to proliferate and producing Th1-type cytokine profile-IL-2 and IFN-gamma. With a semipermeable co-culture system in vitro, antigen-activated CD4+ Th1-like cells were found to promote the proliferation and cytotoxicity of gamma delta T cells via soluble factors.
Conclusion: Functions of gamma delta T cells might be inhanced by CD4+ cells with Th1-type cytokines in antimicrobial immunity.