INTERLEUKIN-10 PRODUCTION BY A B-CELL LINE DERIVED FROM HUMAN POSTTRANSPLANT LYMPHOPROLIFERATIVE DISEASE

Interleukin-10 (IL-10) is a cytokine known to regulate growth and diff erentiation in activated human B cells. We studied IL-10 production in a B-cell line derived from Epstein-Barr virus associated post-transpl ant lymphoproliferative disease (PTLD). Reverse transcriptase polymera se chain reaction (RT-PCR) demonstrated IL-10 mRNA within the cells. T ranscripts of the virally encoded homologue BCRF-1 were not detected. ELISA assays demonstrated translation of IL-10 message into the corres ponding cytokine, and its subsequent secretion into the culture medium . The rate of H-3-thymidine incorporation by the PTLD cells was not af fected by immunologic neutralization of the secreted cytokine, or, by addition of exogenous recombinant IL-10 to the culture medium. Thus, I L-10 does not have an autocrine growth regulatory role in this PTLD li ne.