Observation of T Cell Surface Antigens in the Clinical Course of Adult T-Cell Leukemia: Case Report of a Spontaneous Remission

Abstract

A patient with acute adult T-cell leukemia (ATL) in whom spontaneous remission was observed without any specific treatment having been given is described. The abnormal cell phenotype was CD4+, CD45RO+ and CD8-. As the number of abnormal cells decreased, CD4+ cell count decreased and CD8+ cells and CD45RA+ cells increased to normal levels (45 and 77%, respectively). Further, the number of cells with CD45RO antigen of intermediate fluorescence intensity increased. Five months after admission, we assessed the patient as being in a state of complete clinical remission; no abnormal cells were detected in peripheral blood, lymph node enlargement had disappeared and the serum chemistry was normal. When the abnormal cells in peripheral blood had disappeared, Southern blot analysis for HTLV-I proviral DNA still revealed a weak monoclonal band with EcoRl digestion, and HTLV-I proviral DNA was detected by polymerase chain reaction analysis. Thus, it appeared that very few abnormal cells persisted although the laboratory findings for ATL were normal. Our case could contribute to the understanding of the mechanism that underlies spontaneous remission in ATL.

Serological identification of adult T‐cell leukaemia‐associated antigens

“…At present, there is no effective therapy for ATL. Although conventional chemotherapies do not appear to prolong the life of patients with ATL (Shimoyama et al, 1988;Shimoyama, 1991;Yamada et al, 2001), which is mainly caused by severe infection and drug resistance, spontaneous tumour regression has been described to occur in some ATL patients (Shimamoto et al, 1993;Kawabata et al, 2001), probably because of the immune response against ATL-associated antigens (Suzuki et al, 1995;Jinnohara et al, 1997). Recently, several studies have shown that allogeneic haematopoietic stem cell transplantation (allo-HSCT) could improve the prognosis of ATL patients Kami et al, 2003).…”

Clinical significance of CD45RO expression on peripheral blood mononuclear cells in HTLV‐I‐infected individuals

“…We reported a patient with acute type ATL who went into spontaneous remission and whose CD45RO-FI level was increased during the period of high disease activity and decreased during the phase in which spontaneous remission occurred (Suzuki et al, 1995). This clinical finding suggested that the CD45RO cells are involved in the immune surveillance mechanism in ATL patients.…”

“…Patients with acute type ATL who undergo spontaneous remission may represent a key to solving the problem. We describe a patient with acute type ATL who showed spontaneous remission and whose CD45RO expression on peripheral mononuclear cells (PBMC) changed in parallel with the clinical course from high disease activity to spontaneous remission (Suzuki et al, 1995). This finding suggests that the CD45RO antigen plays a role in the immune surveillance system in ATL patients.…”

Spontaneous Remission in Acute Type Adult T-Cell Leukemia/Lymphoma

“…Since the first case of spontaneous regression of ATL in 1983, more than 20 patients have been reported (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14). Since the first case of spontaneous regression of ATL in 1983, more than 20 patients have been reported (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14).…”