The P2Y11 receptor of human M2 macrophages activates canonical and IL-1 receptor signaling to translate the extracellular danger signal ATP into anti-inflammatory and pro-angiogenic responses

Abstract

The cytoprotective ATP receptor P2Y 11 is upregulated during M2 macrophage differentiation and contributes to the anti-inflammatory properties of this macrophage subset. Here, we studied P2Y 11 -induced reprogramming of human M2 macrophages at the level of mRNA and protein expression. Upregulation of IL-1 receptor (IL-1R) and its known downstream effectors VEGF, CCL20 and SOCS3 as well as downregulation of the ATP-degrading ecto-ATPase CD39 emerged as hallmarks of P2Y 11 activation. The anti-inflammatory signature of the P2Y 11 transcriptome was further characterized by the downregulation of P2RX7, toll-like receptors and inflammasome components. P2Y 11 -induced IL-1R upregulation formed the basis for reinforced IL-1 responsiveness of activated M2 macrophages, as IL-1α and IL-1ß each enhanced P2Y 11 -induced secretion of VEGF and CCL20 as well as the previously reported shedding of soluble tumor necrosis factor receptor 2 (sTNFR2). Raising intracellular cyclic AMP (cAMP) in M2 macrophages through phosphodiesterase 4 inhibition enhanced P2Y 11 -driven responses. The cAMP-binding effector, exchange protein activated by cAMP 1 (Epac1), which is known to induce SOCS3, differentially regulated the P2Y 11 /IL-1R response because pharmacological Epac1 inhibition enhanced sTNFR2 and CCL20 release, but had no effect on VEGF secretion. In addition to cAMP, calcium and protein kinase C participated in P2Y 11 signaling. Our study reveals how P2Y 11 harnesses canonical and IL-1R signaling to promote an anti-inflammatory and pro-angiogenic switch of human M2 macrophages, which may be controlled in part by an Epac1-SOCS3 axis. Supplementary Information The online version contains supplementary material available at 10.1007/s00018-022-04548-z.

P2Y11/IL-1 receptor crosstalk controls macrophage inflammation: a novel target for anti-inflammatory strategies?

“…We used NanoString technology for our gene expression studies [ 19 , 20 , 26 ]. The NanoString nCounter platform uses unique optical barcodes that hybridize to each target mRNA to enable digital counting of individual RNA molecules without any enzymatic amplification steps.…”

“…In contrast to the recombinant cell line, however, IL1A and IL1B upregulation was not significant in macrophages, suggesting that P2Y 11 -activated macrophages are more prone to respond to exogenous IL-1. IL-1R1 upregulation in response to P2Y 11 activation was confirmed at the protein level, initially in the recombinant cell line [ 19 , 26 ] and subsequently in primary human macrophages [ 19 , 20 ].…”

“…The transcriptome analysis in human macrophages also provided further evidence in favor of P2Y 11 as an anti-inflammatory P2Y receptor. The genes encoding NLRP3 inflammasome components (NLRP3, ASC, CASP1) were all downregulated and expression of several toll-like receptors (TLR5, TLR7, TLR8) was also suppressed [ 20 ]. In addition, it provided useful insights into how the receptor's function may be regulated.…”

“…One of the most prominent ATP-hydrolyzing enzymes is the ecto-ATPase CD39 [ 51 ], encoded by ENTPD1, which converts ATP via ADP to AMP. P2Y 11 signaling in human (M2) macrophages appears to be self-sustaining as it delays ATP breakdown by suppressing the expression of CD39, both at the mRNA and the protein level [ 20 ]. Prolonged P2Y 11 signaling through stabilization of its agonist ATP may be critical to the full implementation of the anti-inflammatory program and thus the restoration of homeostasis.…”

“…Several years ago, we have started to examine P2Y 11 function using a transcriptomic approach, first in a recombinant cell line and later in human macrophages [ 19 , 20 ]. A major finding of these studies was P2Y 11 /IL-1 receptor crosstalk.…”