title: Elevated serum levels of soluble Tac peptide in adult T-cell leukemia: correlation with clinical status during chemotherapy.
abstract: Adult T-cell leukemia associated with human T-cell leukemia virus type I (HTLV-I) is characterized by a clonal expansion of a CD4-positive subset of T lymphocytes that constitutively express high numbers of interleukin-2 receptors and that frequently infiltrate the skin; osteolytic bone lesions, and hypercalcemia. Using an enzyme-linked immunosorbent assay (ELISA) test, we measured the level of soluble Tac peptide, one chain of the human interleukin-2 receptor, in the serum of 50 patients with adult T-cell leukemia (38 Japanese and 12 American patients), 8 patients with other hematologic malignancies, 8 asymptomatic HTLV-I-antibody-positive carriers, and 17 normal controls. The serum level of soluble Tac peptide (geometric mean U/mL, 95% CI) was elevated at presentation in all patients with adult T-cell leukemia (16,461; 819 to 330,896) when compared with normal controls (238; 112 to 502), patients with other hematologic malignancies (1302; 475 to 3569), and healthy HTLV-I antibody-positive carriers (490; 115 to 2086). The highest levels were seen in patients (n = 33) with acute (32,154; 2587 to 399,598) compared with chronic (5464; 661 to 45,156) disease (n = 14). Serum levels of Tac peptide also tended to be more elevated in patients with adult T-cell leukemia with hypercalcemia (32,072; 2461 to 417,908) compared with normocalcemic patients (13,885; 496 to 388,436). Serial measurements of soluble Tac peptide levels in serum were done in four patients with adult T-cell leukemia during chemotherapy and the levels reflected disease activity. These observations suggest that the measurement of soluble Tac peptide levels in patients with adult T-cell leukemia is useful as a noninvasive measure of tumor burden and will help in the diagnosis of the disease and management of these patients.
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D006800:Deltaretrovirus Infections / Q000097:blood* / Q000188:drug therapy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D007938:Leukemia / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011971:Receptors, Immunologic / Q000378:metabolism*; D015375:Receptors, Interleukin-2
chemical_list: D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D007770:L-Lactate Dehydrogenase