INFLUENCE OF L-GLUTAMIC ACID ON BINDING OF INTERLEUKIN-1-BETA, TUMOR-NECROSIS-FACTOR-ALPHA AND INTERLEUKIN-6 TO HL-60 CELLS

To elucidate the mechanism of differentiating activity on L-Glu to HL- 60 cells, its influence on binding of human recombinant interleukine-1 beta (rHuIL-1 beta), tumour necrosis factor-alpha (rHuTNF-alpha) and interleukine-6 (IL-6) by HL-60 cells was studied. It was established, that L-Glu converted the high affinity binding of [I-125]rHuIL-1 beta (K-d = 0.32 nM) and [I-125]rHuIL-6 (K-d = 0.075 nM) to HL-60 cells int o low affinity (corresponding K-d values - 13.3 and 2.1 nM) at concent ration 0.1 mu M. The preincubation for an hour of HL-60 cells with 0.1 mu M L-Glu was shown to result in an increase of affinity and number of [I-125]rHuTNF-alpha binding sites. Thus, L-Glu decreases the sensit ivity of the HL-60 cells to IL-1 beta and IL-6 and increases TNF-alpha binding at concentration 0.1 mu M. (C) 1998 Elsevier Science B.V. All rights reserved.