Establishment of a human thymic stromal cell line (R-3-4) and its adhesive capacity with T cells in vitro.

Abstract

T cells are considered to be activated in the thymus, and it has been emphasized recently that the thymic stromal cells play an important role in the process of T-cell maturation. To clarify how the stromal cells interact with T cells a cloned stromal cell line from human thymus was established and its adhesive capacity with T cells was studied. A recombinant plasmid, pSV3gpt containing SV40 large T antigen was introduced to human thymic stroma by the calcium phosphate co-precipitation method, and the thymic stromal cell line R-3-4 was obtained. Immunohistochemical examination showed that R-3-4 possessed with HLA-class 1 antigen, laminin, fibronectin, and keratin. To determine if the R-3-4 interacts with T cells, the binding activity of R-3-4 with T cells examined by using rosette formation technique. The R-3-4 formed rosette only with the T cells, but both B cells and myeloid cells did not bind to the R-3-4. This rosette formation between R-3-4 and T cells was inhibited when T cells were pretreated with anti-CD2 antibodies, suggesting that some mechanism involving CD2 participates in this binding. Our novel established thymic stromal cell line might be useful for studying the interactions between thymic stroma and T cells in vitro.