ABSTRACT
The objective of this study was to investigate the change of native immune adhering function (ENIAF) in self-plasma of patients with hematologic and lymphoid neoplasms and its effect on the killing activity of NK cells. The whole blood was anticoagulated with citric acid. 5 microl precipitated red blood cells and 500 microl plasma of patients or controls were directly mixed with 750 microl quantitative K562 cells at 37 degrees C for 30 minutes. One K562 cell attached by one or more erythrocytes was counted as one rosette, the ratio of rosettes was calculated. Using K562 cells as target cells, the killing activity of NK cells isolated from normal persons was detected by MTT assay, the change of the killing activity was observed after adding RBCs. The results indicated that the ratio of rosettes formed by RBCs of 21 normal controls and K562 cells was 15.3% +/- 6.4%, and the ratio of rosettes formed by RBCs of 24 patients and K562 cells was 7.6% +/- 7.0%. The ability of ENIAF in patients with hematologic and lymphoid neoplasms was significantly lower than that in healthy individuals (t = 3.61, p < 0.001). The killing rate of NK cells in peripheral blood of normal individuals was 67% - 71% without adding RBCs, and it increased by 14.7% +/- 5.2% after adding RBCs of normal controls but decreased by 4.3% +/- 7.6% with RBCs of patients. It is concluded that the ENIAF of RBCs in patients with hematopoietic and lymphoid neoplasms decreases, accompanying the reduction of the killing activity of NK cells to K562 cells, so to detect change of ENIAF may be helpful for the assessment of the immunological function of patients with hematopoietic and lymphoid neoplasms.