Characterization of Extrathymic T Cells Induced by Recombinant Murine Interferon-β in the Peritoneal Cavity of Nude Mice

Abstract

The effects of recombinant murine interferon-β (rMuIFN-β) on extrathymic lymphocyte formation in the peritoneal cavity of BALB/c athymic nude mice and tumor-bearing nude mice were examined for comparison with BALB/c normal euthymic mice. The 7 days of administration of 1 X 10⁵ IU rMuIFN-β caused the number of these cells to increase remarkably in the peritoneal cavity as a unique subset of asialoGM1⁺CD4⁺CD8^-TcRαβ⁺ T cells. The asialoGM1⁺CD4⁺ T cells produced IL-2 and IFN-γ in primary culture without stimulant but did not proliferate. Thus, extrathymic T cells can be induced easily in the peritoneal cavity in addition to the thymus for host defense systems.