Induction of T cell serine proteinase 1 (TSP-1)-specific mRNA in mouse T lymphocytes

An oligonucleotide probe corresponding to nucleotides of a cDNA encoding the T cell-associated proteinase 1 (TSP-1) was chosen to study the induction and expression of TSP-1-specific transcripts in mouse T lymphocytes and tissues. We demonstrate that TSP-1 mRNA is only expressed in activated T lymphocytes and is absent from all mouse tissues tested including those containing resting mature T lymphocytes. Expression of the TSP-1 gene was observed in T lymphocytes in vitro in response to either phorbolester (phorbol 12-myristate 13-acetate), Ca2+ ionophore (A23187), lectin or alloantigen. In general, TSP-1 mRNA appeared and peaked later compared to interleukin 2 transcripts. Furthermore, TSP-1 mRNA was inducible in vitro in both Ly-2+ and L3T4+ lymphocyte populations treated with alloantigen and/or lectin. The transcription of the TSP-1 gene was always accompanied by the expression of proteinase activity. High expression of TSP-1 transcripts was also observed in in vivo derived T effector cells specific for lymphocytic choriomeningitis virus. However, TSP-1 mRNA was predominantly associated with virus-specific Ly-2+ T cells and correlated with their proteinase and cytolytic activities. The data suggest that TSP-1 gene transcription is a useful marker to characterize T effector cells in vitro and in vivo.