title: Resistance of some leukemic blasts to lysis by lymphokine activated killer (LAK) cells.
abstract: Peripheral blood mononuclear cells (PBMC) from healthy donors and AML patients in remission were stimulated with phytohemagglutinin (PHA) and recombinant interleukin-2 (IL-2). These stimulated cells (lymphokine activated killer (LAK) cells) showed increased DNA synthesis as measured by 3H-Thymidine uptake. A synergistic effect of PHA and IL-2 was found. LAK cells' ability to kill acute myeloid leukemia (AML) blasts was investigated by the 51Cr release assay. LAK cells showed a cytotoxicity (over 10% specific 51Cr release) against 9/12 leukemic blasts, even at effector/target (E/T) ratios as low as 5:1. However, on average only 22.2% (SD 11.8) and 36.5% (SD 12.5) 51Cr release were obtained in 4- and 18-hour cytotoxicity assays, respectively, at an E/T ratio of 20:1. Leukemic blasts in 3/12 AML cases and normal PBMC were entirely resistant to lysis, even at an E/T ratio of 80:1. Susceptibility to lysis was not correlated to peanut-agglutinin receptor expression. LAK cells were more cytotoxic towards the K-562 cell line (natural killer activity) than unstimulated PBMC.
authors.affiliation: Division of Hematology, Karolinska Hospital, Stockholm, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Panayotides
authors.forename: A
authors.initials: A
authors.lastname: Porwit
authors.forename: A M
authors.initials: AM
authors.lastname: Sjögren
authors.forename: J
authors.initials: J
authors.lastname: Wasserman
authors.forename: P
authors.initials: P
authors.lastname: Reizenstein
mesh_terms: D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000276:immunology*; D015470:Leukemia, Myeloid, Acute / Q000276:immunology*; D008213:Lymphocyte Activation; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D007376:Interleukin-2; D011994:Recombinant Proteins