High establishment efficiency of lymph node stromal cells which spontaneously produce multiple cytokines derived from adult T-cell leukemia/lymphoma patients.

Stromal cells isolated from lymph nodes of adult T-cell leukemia/lymphoma (ATL) patients were cultured. Such lymph node stromal cells (LNSC) could be maintained for more than one year, whereas LNSC from other lymphoproliferative disorders ceased to proliferate within months. The rate of human T lymphotropic virus type I (HTLV-I) integration in these LNSC was examined by nested polymerase chain reaction (PCR) and estimated to be about 1 genome per 100 cells. These LNSC showed the same combination of cytokine production irrespective of the patient origin, granulocyte-macrophage (GM)-CSF, G-CSF, interleukin (IL)-1 beta, IL-6, interferon (IFN)-gamma and IL-8, being positive but not M-CSF, IL-1 alpha, IFN-alpha, tumor necrosis factor (TNF)-alpha, IL-2, LD78 and the IL-1 receptor antagonist (IL-1ra). The results show that LNSC from ATL patients have pronounced proliferation activity and constitutively secrete various cytokines. They therefore provide useful models for studying the microenvironment of lymph nodes in vitro, and especially the growth mechanism of ATL cells.