Evidence for opioid receptors on cells involved in host defense and the immune system

Burt M. Sharp, Sabita Roy, Jean M. Bidlack

Research output: Contribution to journalArticlepeer-review

156 Scopus citations


Although the role of opiates and opioids in the physiological and pathological function of the immune system is only beginning to be unraveled, converging lines of evidence indicate that the opioid receptors expressed by immune cells are often the same or similar to the neuronal subtypes, particularly δ and κ. Recent studies also point to the existence of novel opioid receptors and/or binding sites on immune cells that are selective for morphine. Opioids and their receptors, particularly those with high affinity for δ agonists, appear to function in an autocrine/paracrine manner. Thus, opioid peptides generated from immune-derived proenkephalin A act as cytokines, capable of regulating myriad functions of both granulocytes and mononuclear cells. Further identification and characterization of receptors and signal transduction pathways that account for some of the unique properties of opiate binding and immunomodulation (e.g., dose-dependent effects of morphine that occur at exceptionally low concentrations relative to the K(d)'s of the neuronal μ receptor or the morphine binding site reported on activated human T-cells) represents one of the major research challenges ahead. Elucidating mechanisms, such as these, may provide unique therapeutic opportunities through the application of opioid immunopharmacology to disorders involving immune responses in peripheral organs and the central nervous system.

Original languageEnglish (US)
Pages (from-to)45-56
Number of pages12
JournalJournal of Neuroimmunology
Issue number1-2
StatePublished - Mar 15 1998

Bibliographical note

Funding Information:
This work was supported by NIDA DA-04196 (B. Sharp), DA-08188 (S. Roy), DA-04355 (J. Bidlack) and DA-09676 (J. Bidlack).


  • Delta
  • Kappa
  • Mu


Dive into the research topics of 'Evidence for opioid receptors on cells involved in host defense and the immune system'. Together they form a unique fingerprint.

Cite this