The development of chimeric antigen receptor (CAR) T-cell therapies has been opening a new era in cell-based immunotherapy. However, like classical medicine-based therapies, efficiency of functional cell delivery toward target organs and cells is crucial for producing beneficial and adverse-effects of the cell-based therapy. To explore the pathogenesis of allergy diseases, we have been developing new mouse models of allergic inflammation, especially focusing the role of antigen-specific T cells. Antigen administration to mice transferred with in vitro-differentiated antigen-specific T cells evokes inflammatory responses at the site of antigen exposure. In response to chemokines produced and with the usage of several cell adhesion molecules upregulated, allergen-specific T cells efficiently recruit and proliferate in the inflammation sites. T cell has capacity to obtain various immune-regulatory properties following in vitro culture under specific conditions. Large number of T cells expressing T cell receptors reactive to specific antigens can be prepared by employing somatic cell nuclear transfer techniques. I would like to provide these data probably helpful for considering new cell delivery system in cell-based immunotherapy.