title: Thy-1+ epidermal cells proliferate in response to concanavalin A and interleukin 2.
abstract: Mouse epidermal cells (EC) are composed of at least two phenotypically discrete populations of cells that in epidermal sheets have a dendritic morphology: Ia+ Langerhans cells (LC) and dendritic, bone marrow-derived, Ia- cells that express Thy-1 antigen (Thy-1+ dEC). Thy-1+ dEC lack other typical T cell markers such as L3T4, Lyt-1, and Lyt-2; however they do express Ly-5 and asialo GM1 in common with NK cells and certain other leukocytes. To investigate the functional capabilities of Thy-1+ dEC in vitro, cell suspensions prepared from trypsin-disaggregated sheets of mouse body wall epidermis were first enriched to 8 to 20% Ia+ and 20 to 40% Thy-1+ cells by centrifugation over Isolymph and then were cultured for 2 to 10 days with Concanavalin A (Con A) and/or partially purified rat IL 2. Con A-induced proliferation of EC was readily seen, with the maximal response occurring at a Con A concentration of 2.5 micrograms/ml on day 5 of culture. Con A responses were significantly enhanced by the continuous presence of 1 microgram/ml indomethacin. Responses both in the presence and absence of Con A were significantly enhanced by the addition of 5 to 10 U/ml of partially purified rat IL 2; proliferation in cultures stimulated by both Con A and IL 2 continued to increase throughout the 10-day culture period. Culture of fluorescence-activated cell sorter (FACS)-separated EC suspensions revealed that Thy-1-depleted EC and irradiated Thy-1+ EC failed to proliferate in response to Con A and IL 2, whereas unirradiated purified Thy-1+ EC gave enhanced Con A- and IL 2-induced responses compared with the unseparated population. Finally, to distinguish between the proliferation of small numbers of mature peripheral T cells and that of Thy-1+ dEC, antibody and complement-depletion studies were conducted with an unusual monoclonal anti-Thy-1 reagent, 20-10-5S, and with the anti-T cell reagents, anti-L3T4 and anti-Lyt-2. Thy-1+ dEC, but not LC, express the 20-10-5S determinant; furthermore, in CBA (Thy-1.2) mice 20-10-5S reacts with Thy-1+ dEC, thymocytes, and peripheral T cells, whereas in AKR/J (Thy-1.1) mice, it reacts only with Thy-1+ dEC and thymocytes and not with peripheral T cells. Pretreatment of AKR/J EC with 20-10-5S and complement abolished the capacity of such cells to respond to Con A and to IL 2.(ABSTRACT TRUNCATED AT 400 WORDS)
authors.forename: J L
authors.initials: JL
authors.lastname: Nixon-Fulton
authors.forename: P R
authors.initials: PR
authors.lastname: Bergstresser
authors.forename: R E
authors.initials: RE
authors.lastname: Tigelaar
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis / Q000276:immunology; D002455:Cell Division / Q000187:drug effects; D002469:Cell Separation / Q000379:methods; D002499:Centrifugation, Density Gradient; D003208:Concanavalin A / Q000494:pharmacology*; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology*; D005260:Female; D007376:Interleukin-2 / Q000502:physiology*; D051379:Mice; D008806:Mice, Inbred AKR; D008809:Mice, Inbred C3H; D008808:Mice, Inbred CBA; D010641:Phenotype; D013535:Suspensions; D018800:Thy-1 Antigens
chemical_list: D000954:Antigens, Surface; D007376:Interleukin-2; D013535:Suspensions; D018800:Thy-1 Antigens; D003208:Concanavalin A