Expression of inhibitory receptor ILT3 on neoplastic B cells is associated with lymphoid tissue involvement in chronic lymphocytic leukemia

Autor: Lawrence Tsao, Govind Bhagat, Su Wang, Nicole Suciu-Foca, Bachir Alobeid, Julie G. Fisher, Manuel Menes, Tetsunori Seki, Hana Lin, Adriana I. Colovai, Chuan Wang
Rok vydání: 2007
Předmět:
Zdroj: Cytometry Part B: Clinical Cytometry. :354-362
ISSN: 1552-4957
1552-4949
DOI: 10.1002/cyto.b.20164
Popis: T cell responses against leukemia-associated antigens have been reported in chronic lymphocytic leukemia (CLL). However, the relentless accumulation of CLL B cells in some patients indicates that anti-tumor immune responses are inefficient. Inhibitory receptors from the Ig-like transcript (ILT) family, such as ILT3 and ILT4, are crucial to the tolerogenic activity of antigen presenting cells. In this study, we examined the expression of ILT3 on CD5+ B cells obtained from 47 patients with CLL. Using flow cytometry and RT-PCR, we found that B CLL cells from 23 of 47 patients expressed ILT3 protein and mature ILT3 mRNA. ILT3 protein and mRNA were not found in normal B cells obtained from donors without CLL. Expression of ILT4 in normal and B CLL cells showed a pattern similar to ILT3. The frequency of ILT3 positive CLL B cells was higher in patients with lymphoid tissue involvement, suggesting that ILT3 may have prognostic value in CLL. Our findings indicate that expression of ILT3 and ILT4 on CLL B cells represents a phenotypic abnormality that may play a role in tolerization of tumor-specific T cells.
Databáze: OpenAIRE