Autoantibodies to the δ-opioid receptor function as opioid agonists and display immunomodulatory activity

Received 21 August 2009; received in revised form 7 October 2009; accepted 9 October 2009. published online 02 November 2009.

Abstract

In this report, we show that affinity purified human anti-delta opioid receptor (DOR) autoantibodies from IVIG are specific to DOR and possess agonistic properties displayed by their ability to dramatically decrease forskolin stimulated cAMP accumulation. Anti-DOR autoantibody also caused phosphorylation of the opioid receptor. Anti-DOR autoantibody treatment showed a significant reduction in CXCR4 gene expression as well as surface protein expression. In contrast, anti-DOR autoantibody treatment significantly upregulated CCR5 gene and protein expression. The presence of anti-DOR autoantibodies in IVIG and their potent immunomodulatory activity is further evidence to support the cross-talk between the neuroendocrine and immune systems.

Keywords: Opioid receptors, Autoantibodies, Immunomodulation

a Department of Immunobiology, University of Arizona, 1656 E. Mabel Street, PO Box 245221, Tucson, Arizona 85724, USA

b Arizona Arthritis Center, University of Arizona, 1656 E. Mabel Street, PO Box 245221, Tucson, Arizona 85724, USA

Corresponding author. Tel.: +1 520 626 7013; fax: +1 520 626 2100.

PII: S0165-5728(09)00399-3

doi:10.1016/j.jneuroim.2009.10.007

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