Monocytes expressing CX3CR1 orchestrate the development of vincristine-induced pain
Elizabeth A. Old, … , Mauro Perretti, Marzia Malcangio
Elizabeth A. Old, … , Mauro Perretti, Marzia Malcangio
Published April 17, 2014
Citation Information: J Clin Invest. 2014;124(5):2023-2036. https://doi.org/10.1172/JCI71389.
View: Text | PDF
Research Article Neuroscience

Monocytes expressing CX3CR1 orchestrate the development of vincristine-induced pain

Abstract

A major dose-limiting side effect associated with cancer-treating antineoplastic drugs is the development of neuropathic pain, which is not readily relieved by available analgesics. A better understanding of the mechanisms that underlie pain generation has potential to provide targets for prophylactic management of chemotherapy pain. Here, we delineate a pathway for pain that is induced by the chemotherapeutic drug vincristine sulfate (VCR). In a murine model of chemotherapy-induced allodynia, VCR treatment induced upregulation of endothelial cell adhesion properties, resulting in the infiltration of circulating CX3CR1+ monocytes into the sciatic nerve. At the endothelial-nerve interface, CX3CR1+ monocytes were activated by the chemokine CX3CL1 (also known as fractalkine [FKN]), which promoted production of reactive oxygen species that in turn activated the receptor TRPA1 in sensory neurons and evoked the pain response. Furthermore, mice lacking CX3CR1 exhibited a delay in the development of allodynia following VCR administration. Together, our data suggest that CX3CR1 antagonists and inhibition of FKN proteolytic shedding, possibly by targeting ADAM10/17 and/or cathepsin S, have potential as peripheral approaches for the prophylactic treatment of chemotherapy-induced pain.

Authors

Elizabeth A. Old, Suchita Nadkarni, John Grist, Clive Gentry, Stuart Bevan, Ki-Wook Kim, Adrian J. Mogg, Mauro Perretti, Marzia Malcangio

×

Figure 5

Vincristine treatment activates endothelial cells.

Options: View larger image (or click on image) Download as PowerPoint
Vincristine treatment activates endothelial cells. (A–C) Expression of a...
(A–C) Expression of adhesion molecules VCAM-1 and ICAM-1 by primary HUVECs is increased by VCR (10 nM) or TNF-α (10 ng/ml) compared with control (cell media) following 18-hour incubation. (A) Representative plots for cells stained for CD31 and VCAM-1. (B) Cumulative data for CD31/VCAM-1 double-positive HUVECs. (C) ICAM-1 and CD31 levels on HUVECs. MFI, median fluorescence intensity (units). (B and C) Mean ± SEM of 3 distinct experiments. C, control, treated with media only. *P < 0.05, **P < 0.001 compared to saline, 1-way ANOVA followed by Tukey post-hoc test. (D and E) The expression of mature FKN protein in HUVECs is unchanged by incubation in VCR (10 nM for 30 minutes; n = 3 cultures). (D) Quantification of band density calculated using Bio-Rad’s Quantity One software and normalized to GAPDH loading control. (E) Representative blot of FKN and GAPDH loading control in HUVEC lysates. (F and G) FKN expression by endothelial cells in vivo is unchanged by VCR treatment. (F) Representative photomicrographs showing expression of FKN-mCherry in CD31+ (endothelial) cells in transverse sciatic nerve sections obtained from Cx3cl1mcherry mice treated with either saline or 2 cycles of VCR. Scale bar: 100 μm; 50 μm (inset). (G) No change in (FKN)mcherry+CD31+ cells in the sciatic nerves after 1 day of VCR and at end of VCR cycles. The number of CD31+ cells that are positive for (FKN)mcherry was calculated following counting in whole nerve sections (mean ± SEM, n = 4 mice per group).