Fujii S. Role of interferon-alpha and clonally expanded T cells in the immunotherapy of chronic myelogenous leukemia.
Leuk Lymphoma 2000;
38:21-38. [PMID:
10811445 DOI:
10.3109/10428190009060316]
[Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Twenty five percent of patients in the chronic phase of chronic myelogenous leukemia (CML) are treated with interferon-alpha (IFN-alpha) to induce a cytogenic remission. In addition to its direct effects on leukemic cells, IFN-alpha has been shown to induce immunologic alterations, including upregulation of the expression of major histocompatibility (MHC) antigens in antigen-presenting cells (APCs), as well as augmentation of the activity of the lymphocytes against tumor cells. However, there has been little direct evidence supporting a causal interaction between cellular immunoreactivity and clinical responsiveness to IFN-alpha. We have shown that one approach to elucidate the immunological mechanisms by which IFN-alpha exerts its anti-CML activity is by analyzing therapy-induced modulation in T-cell receptor (TCR) Vbeta chain usage, using the reverse transcription-polymerase chain reaction (RT-PCR) followed by single-strand conformation (SSCP) analysis. This method is particularly attractive, since it provides an index of antigen-specific T cell expansion, but does not require the extraction and purification of the antigens involved in the T-cell response. T cell clones that express the Vbeta 10, 12, and 14 families predominate in the peripheral blood (PB) of CML patients. The enhanced expression of the Vbeta 9 and 20 families has been detected in IFN-alpha responsive patients but not patients who are poorly responsive to this agent. This suggests that expansion of T cells expressing these TCR Vbeta gene families may serve as a prognostic factors of the clinical responsiveness of CML patients to IFN-alpha. In addition, since T cell clones that express certain Vbeta families may react with a discrete set of antigenic peptides presented on the surface of malignant cells, a better understanding of the immunobiology of T cells in CML may allow for the design of increasing efficacious immune therapy for this disease.
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