The effects of tacrolimus and transformation growth factor beta (TGF-beta1) on Langerhans cell (LC) differentiation of their epidermal precursors were studied. Tacrolimus and TGF-beta1 act synergistically on LC generation and the expression of CD40, CD80, CD86, CD83 and MHC-II. The combination stabilizes TGF-beta receptor II expression and decreased LC stimulatory capacity towards T-cells. The therapeutic effects of tacrolimus may depend on adjusting the balance of the dendritic cell population to favor LC formation (Kwiek, B. et al. J Allergy Clin Immunol 2008, 122[1]: 126-132).