TY - JOUR
T1 - Different functions for the interleukin 8 receptors (IL-8R) of human neutrophil leukocytes
T2 - NADPH oxidase and phospholipase D are activated through IL-8R1 but not IL-8R2
AU - Jones, S. A.
AU - Wolf, M.
AU - Qin, S.
AU - Mackay, C. R.
AU - Baggiolini, M.
PY - 1996/7/26
Y1 - 1996/7/26
N2 - Two monoclonal antibodies, anti-IL8R1 and anti-IL8R2, raised against both interleukin 8 receptors (IL-8R) of human neutrophils, IL-8R1 and IL- 8R2, were used to study individual receptor functions after stimulation with IL-8, GROα, or NAP-2. Efficacy and selectivity of the antibodies were tested in Jurkat cells transfected with cDNA coding for one or the other receptor. The binding of 125I-labeled IL-8 and IL-8-induced changes of the cytosolic free Ca2+ concentration were inhibited by anti-lL8Rl in cells expressing IL-8R1 and by anti-IL8R2 in cells expressing IL-8R2. In human neutrophils, release of elastase was observed after stimulation with IL-8 or GROα. The response to IL-8 was inhibited slightly by anti-IL8R1 and more substantially when both monoclonal antibodies were present, while the response to GROα was inhibited by anti-IL8R2 but was not affected by anti-IL8R1. These results indicate that both IL-8 receptors can signal independently for granule enzyme release. Superoxide production, a measure of the respiratory burst, was obtained with increasing concentrations of IL-8 with maximum effects at 25 to 50 nM, but no response was observed upon challenge with GROα or NAP-2 up to 1000 nM. The superoxide production induced by IL-8 was inhibited by anti- IL8R1, but was not affected by anti-IL8R2. Stimulation of neutrophils with IL-8, in contrast to GROα or NAP-2, also elicited phospholipase D activity. The effect of IL-8 was again inhibited by anti-IL8R1 but not by anti-IL8R2, indicating that this response, like the respiratory burst, was mediated by IL-8R1. Taken together, our results show that IL-8R1 and IL-8R2 are functionally different. Responses, such as cytosolic free Ca2+ changes and the release of granule enzymes, are mediated through both receptors, whereas the respiratory burst and the activation of phospholipase D depend exclusively on stimulation through IL-8R1.
AB - Two monoclonal antibodies, anti-IL8R1 and anti-IL8R2, raised against both interleukin 8 receptors (IL-8R) of human neutrophils, IL-8R1 and IL- 8R2, were used to study individual receptor functions after stimulation with IL-8, GROα, or NAP-2. Efficacy and selectivity of the antibodies were tested in Jurkat cells transfected with cDNA coding for one or the other receptor. The binding of 125I-labeled IL-8 and IL-8-induced changes of the cytosolic free Ca2+ concentration were inhibited by anti-lL8Rl in cells expressing IL-8R1 and by anti-IL8R2 in cells expressing IL-8R2. In human neutrophils, release of elastase was observed after stimulation with IL-8 or GROα. The response to IL-8 was inhibited slightly by anti-IL8R1 and more substantially when both monoclonal antibodies were present, while the response to GROα was inhibited by anti-IL8R2 but was not affected by anti-IL8R1. These results indicate that both IL-8 receptors can signal independently for granule enzyme release. Superoxide production, a measure of the respiratory burst, was obtained with increasing concentrations of IL-8 with maximum effects at 25 to 50 nM, but no response was observed upon challenge with GROα or NAP-2 up to 1000 nM. The superoxide production induced by IL-8 was inhibited by anti- IL8R1, but was not affected by anti-IL8R2. Stimulation of neutrophils with IL-8, in contrast to GROα or NAP-2, also elicited phospholipase D activity. The effect of IL-8 was again inhibited by anti-IL8R1 but not by anti-IL8R2, indicating that this response, like the respiratory burst, was mediated by IL-8R1. Taken together, our results show that IL-8R1 and IL-8R2 are functionally different. Responses, such as cytosolic free Ca2+ changes and the release of granule enzymes, are mediated through both receptors, whereas the respiratory burst and the activation of phospholipase D depend exclusively on stimulation through IL-8R1.
KW - enzyme release
KW - GROα
KW - NAP-2
KW - neutrophil activation
KW - respiratory burst
UR - http://www.scopus.com/inward/record.url?scp=0029900788&partnerID=8YFLogxK
U2 - 10.1073/pnas.93.13.6682
DO - 10.1073/pnas.93.13.6682
M3 - Article
C2 - 8692878
AN - SCOPUS:0029900788
SN - 0027-8424
VL - 93
SP - 6682
EP - 6686
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 13
ER -