XXXX -stimulated aortic endothelial cells secrete a novel T lymphocyte chemotactic and growth factor.

@entity1 @entity32 @entity1619 @entity69 @entity750 @entity2902 @entity731 @entity9186 @entity291
@entity731 contain multiple cell types including smooth muscle cells, macrophages, and T lymphocytes. The development of an extralymphatic T lymphocyte focus of @entity32 in this condition requires chemoattractant-induced cell migration and growth factor-induced cell activation. In a previous study, we described a novel 13-15-kDa T lymphocyte-specific chemotactic cytokine, @entity1619 ( @entity1619 ), secreted by @entity750 -stimulated @entity291 aortic endothelial cells that is distinct from previously identified endothelial cell-derived interleukins (IL) 1, 6, and 8. Because of the association between T lymphocyte chemotactic and growth factor activity, in the current study we investigated the effect of @entity1619 on T cell growth. We assessed its capacity to induce markers of the passage of T cells from the resting (G0) state into the G1 phase of the cell cycle, such as receptors for @entity2902 ( @entity2902 ) and @entity69 ( @entity69 ) and class II major histocompatibility complex antigens (HLA-DR). Incubation of G0 freshly isolated @entity1 T lymphocytes for 48 h with chromatographically resolved, partially purified @entity1619 resulted in a threefold increase in expression of the @entity2902 subunit of @entity2902 , a threefold increase in @entity69 , and a twofold increase in HLA-DR. Passage into the G1 phase of the cell cycle was confirmed by cell cycle analysis employing @entity9186 . Evaluation of CD4+ and CD8+ T cell subsets by double-antibody labeling demonstrated that the @entity2902 subunit of @entity2902 was induced in both T cell subsets. Although incubation of @entity1 T cells with @entity1619 alone did not induce proliferation, addition of exogenous @entity2902 to T cells pulsed with @entity1619 for 24 h caused a proliferative response with a stimulation index of 3. By up-regulating functional cell surface receptors for @entity2902 , @entity1619 is a competence growth factor for T lymphocytes and primes them to respond to @entity2902 . By virtue of its effect on T cells, as a chemotactic and competence factor, this endothelial cell-derived mitoattractant could participate with other T cell growth factors like @entity2902 in the recruitment and amplification of the extralymphatic T cell component of @entity731 .
