Hodgkin and Reed-Sternberg cells of Hodgkin lymphoma Interleukin 13 and interleukin 13 receptor are frequently expressed by

Hodgkin lymphoma (HL) is characterized by the abnormal expression of multiple cytokines, accounting for its unique clinicopathologic features. We have previously shown that interleukin-13 (IL-13) is secreted by HL cell lines and may serve as an autocrine growth factor. To determine the frequency of IL-13 expression in lymphoma patients, tissue sections from 36 patients with classical HL, 5 patients with nodular lymphocyte predominance HL (NLPHL), and 23 patients with non-Hodgkin lymphoma (NHL) were subjected to in situ hybridization. In 31 of 36 cases (86%) of classical HL patients of all histologic subtypes, between 25% to almost 100% of Hodgkin and Reed Sternberg (HRS) cells were positive for IL-13 expression. In contrast, in no case of NLPHL and in only 4 of 23 NHL cases (1 of 5 T-cell-rich B-cell lymphomas, 2 of 5 anaplastic large cell lymphomas, and 1 of 5 peripheral T-cell lymphomas) did the neoplastic cells express IL-13. The expression of the IL-13 receptor chain alpha1 (IL-13 alpha1) was also analyzed by in situ hybridization. In 24 of 27 (89%) cases of classical HL, between 25% to 75% of HRS cells, as well as a high frequency of lymphocytes and histiocytes, were positive for IL-13R alpha1 expression. These results were confirmed by the construction of complementary DNA libraries from single HRS cells, followed by polymerase chain reaction analysis, in which IL-13R alpha1 transcripts were found to be present in all 6 cases of HL. These data indicate that expression of IL-13 and IL-13R alpha1 is a common feature of HRS cells in HL, consistent with the hypothesis that IL-13 may play a role in autocrine growth in classical HL, (C) 2001 by The American Society of Hematology.