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Query: UNIPROT:P10145 (
IL-8
)
23,849
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The CXC chemokine,
IL-8
, is a potent chemoattractant of neutrophils and binds to two distinct receptors, termed IL-8R1 and IL-8R2. These receptors share high affinity for
IL-8
, however, only IL-8R1 is specific for
IL-8
whereas IL-8R2 binds other related chemokines, including GRO alpha with high affinity. Stable Jurkat transfectants were generated expressing either functional IL-8R1 or IL-8R2 (J-IL8R1 and J-
IL8R2
). Both J-IL8R1 and J-
IL8R2
exhibited high affinity
IL-8
binding (Kd 3-5 nM) with respective receptor densities of 23,000 +/- 3,000 and 18,500 +/- 1,500. Pre-treatment of both transfectants with 1.0 micrograms/ml B. pertussis toxin (PTx) resulted in inhibition of
IL-8
mediated intracellular Ca2+ mobilisation and chemotaxis, without altering the receptor's affinity for its ligand. This indicates that both receptors couple to a PTx-sensitive G-protein. Further studies showed that IL-8R1 and IL-8R2 could mediate time-dependent phosphorylation of p42/p44 MAP-kinase. In both transfectants, phosphorylation was maximal at 1-2 min after
IL-8
stimulation and could be inhibited by PTx. Stimulation of J-IL8R1 and J-
IL8R2
with GRO alpha revealed that this chemokine was a more potent activator of MAP-kinase in J-
IL8R2
, an observation reflected in the high affinity binding of GRO alpha to IL-8R2. These studies indicate that chemokines are capable of activating protein kinases and with regards to PTx-sensitivity and MAP-kinase stimulation, no significant differences between IL-8R1 and IL-8R2 post-receptor signalling occur during cell activation by
IL-8
.
...
PMID:A comparison of post-receptor signal transduction events in Jurkat cells transfected with either IL-8R1 or IL-8R2. Chemokine mediated activation of p42/p44 MAP-kinase (ERK-2). 775 May 73
Neutrophil leukocytes, the target cells for interleukin-8 and related CXC chemokines, bear high numbers of two types of
IL-8
receptors (IL-8R1 and IL-8R2). By cDNA transfection Jurkat cell lines were generated that stably express either IL-8R1 or IL-8R2 (J-IL8R1 and J-
IL8R2
). J-IL8R1 expressed 4,000 +/- 1,000 copies of IL-8R1, and bound
IL-8
with high affinity (Kd 1-4 nM) and GRO alpha and NAP-2 with low affinity (Kd 200-500 nM). J-
IL8R2
expressed 17,000 +/- 3,000 copies of IL-8R2, and bound all three chemokines with high affinity. Both transfectants showed a similar degree of chemotactic migration after stimulation with
IL-8
, GRO alpha and NAP-2. All three chemokines were equally potent as attractants of J-
IL8R2
, whereas
IL-8
was 300 to 1,000-fold more potent than GRO alpha or NAP-2 as attractant of J-IL8R1. The potencies, therefore, agree with the affinities of the ligands to IL-8R1 and IL-8R2. Our results demonstrate that both
IL-8
receptors function independently, and mediate chemotaxis in response to
IL-8
and other CXC chemokines.
...
PMID:Both interleukin-8 receptors independently mediate chemotaxis. Jurkat cells transfected with IL-8R1 or IL-8R2 migrate in response to IL-8, GRO alpha and NAP-2. 813 38
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
, GRO alpha, 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 125 I labeled
IL-8
and
IL-8
-induced changes of the cytosolic free Ca2+ concentration were inhibited by anti-IL8RI 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 GRO alpha. The response to
IL-8
was inhibited slightly by anti-IL8R1 and more substantially when both monoclonal antibodies were present, while the response to GRO alpha 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 GRO alpha 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 GRO alpha or NAP-2, also elicited phospholipase D activity. The effect of
IL-8
was again inhibited by anti-IL-8R1 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.
...
PMID:Different functions for the interleukin 8 receptors (IL-8R) of human neutrophil leukocytes: NADPH oxidase and phospholipase D are activated through IL-8R1 but not IL-8R2. 869 78