EXPRESSION OF THE COMMON CYTOKINE RECEPTOR-GAMMA CHAIN BY MURINE DENDRITIC CELLS INCLUDING EPIDERMAL LANGERHANS CELLS

The common cytokine receptor gamma chain (gamma(c)) is an indispensabl e component of interleukin (IL)-2, IL-4, IL-7, IL-9, and IL-15 recepto rs, and its expression has been detected in several leukocyte populati ons, including T cells, B cells, monocytes, natural killer cells, and neutrophils. The purpose of this study was to determine whether gamma( c) receptors are expressed by dendritic cells (DC). Constitu tive gamm a(c) mRNA expression was observed by reverse transcription polymerase chain reaction and/or Northern blotting for: (a) Ia(+) epidermal Lange rhans cells (LC), (b) 4F7(+) splenic DC, (c) granulocyte/macrophage co lony-stimulated factor-propagated bone marrow-derived DC, and (d) the epidermal-derived DC line, XS52, which retains important functions of epidermal LC. Exposure of XS52 cells to recombinant IL-4 induced a rap id up-regulation of c-myc mRNA expression, and this IL-4-dependent sig naling was blocked almost completely by anti-;gamma, monoclonal antibo dy (mAb) TUGm2 in a soluble form. Moreover, c-myc up-regulation was in ducible in XS52 cells by the same mAb in an immobilized form. These re sults imply that molecules recognized by this antibody (i.e. gamma(c) receptors) are expressed on XS52 cell surfaces. We thus conclude that DC express functional gamma(c) receptors, which then mediate cytokine- dependent regulation of DC functions.