Natural killer activity and antibody-dependent cellular cytotoxicity in patients with adult T-cell leukemia.
Natural killer (NK) activity of peripheral mononuclear cells (PMNC) from patients with adult T-cell leukemia (ATL), anti-HTLV-I antibody positive healthy carriers, and anti-HTLV-I antibody negative healthy persons (Ab-negative persons) was investigated using various target cells. PMNC from patients with ATL and healthy carriers had reduced NK activity against the NK-sensitive non-HTLV-I producing target cells, compared with the controls. In contrast, PMNC from patients with ATL, healthy carriers, and Ab-negative persons did not exhibit significant NK cell lysis against HTLV-I producing cells. However, one Ab-negative person exhibited increased NK cell lysis against an HTLV-I producing target cell. The effector cells involved in this enhanced cytolysis were found to be CD3+, HNK-1+, and CD8+. HTLV-I producing cells were lysed by PMNC from Ab-negative persons in the presence of anti-HTLV-I antibody (antibody-dependent cellular cytotoxicity; ADCC). The efficiency did not show significant difference between antibodies from patients with ATL and those from healthy carriers. The ADCC was specific to HTLV-I producing cells. PMNC from one patient with ATL in remission exhibited increased ADCC in the presence of autologous serum against HTLV-I, whereas PMNC from a patient with ATL or a healthy carrier did not exhibit ADCC. These results indicated that NK and K cells influence the immunological surveillance against HTLV-I infection or leukemic cells.
Uno
H
H
Kawano
K
K
Matsuoka
H
H
Tsuda
K
K
D000920:Antibody-Dependent Cell Cytotoxicity / Q000276:immunology*; D002460:Cell Line; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000276:immunology*