[The precursors and effectors of human lymphokine-activated killer (LAK) cells].
Natural killer cells were enriched in the second fraction (F2) of discontinuous Percoll density gradients from human PBL after centrifugation, whereas T lymphocytes were enriched in F4. The cytotoxicity against K562 by F2 LAK (F2 cells activated by rIL2) was higher than that of F2 cells. F2 LAK also acquired the ability to lyse NK-resistant tumor cell lines and noncultured lung cancer cells (6 out of 9 cases). All these activities of F2 LAK cells were significantly higher than those of F4 LAK cells. Besides, F2 LAK exhibited higher level of lysis against noncultured lung cancer cells than did LAK derived from PBL. Enzyme-labeled immunocytochemistry staining showed that the number of CD16+ and CD8+ cells in F2 was much more than that in F4. So the higher lytic ability of F2 LAK might come from two kinds of precursors: CD16+ typical NK cells and MHC unrestricted CD8+, NK-like' cytotoxic T lymphocytes. The number of CD4+ cells in F4 was much more than that in F2. They shouldn't be the precursors of LAK cells, otherwise the lytic ability of F4 LAK should be higher than that of F2 LAK. After being cultured with rIL2 for 3 days, F2 cells exhibited proliferative response. But the percentage of CD16+ and CD8+ cells in F2 LAK did not change much, and remained much higher than that in F4 LAK. So the effector cells of short-term cultured LAK might be the activated CD16+ NK cells and CD8+, NK-like' cytotoxic T lymphocytes as well.(ABSTRACT TRUNCATED AT 250 WORDS)
Guo
X
X
Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing.
D000911:Antibodies, Monoclonal; D016827:CD8 Antigens / Q000276:immunology; D002478:Cells, Cultured; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology*; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology*; D017452:Receptors, IgG / Q000276:immunology; D011994:Recombinant Proteins; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D016827:CD8 Antigens; D007376:Interleukin-2; D017452:Receptors, IgG; D011994:Recombinant Proteins