title: The influence of opioids on the humoral and cell-mediated immune responses in mice. The role of macrophages.
abstract: BACKGROUND
  Our experiments were aimed to test the influence of treatment with different opioids (morphine, fentanyl, methadone) on the humoral and cell-mediated immune responses.
  
  
  METHODS
  Mice were treated intraperitoneally (ip) with opioids for several days and next either immunized with sheep red blood cells (SRBC) to test the antibody production or skin-sensitized with hapten picryl chloride (PCL) to induce contact hypersensitivity (CHS). In addition, the effects of opioids on the production of reactive oxygen intermediates (ROIs) and cytokines by peritoneal macrophages (Mf) and on the expression of surface markers on these cells and blood leukocytes were estimated.
  
  
  RESULTS
  Opioids caused an enhancement of ROIs and cytokines production when macrophages were stimulated with zymosan or lipopolysaccharide (LPS) and reduced the expression of antigen presentation markers on Mf. Numbers of anti-SRBC plaque forming cells (PFC) and antibodies titres were lower in mice treated with all tested opioids. Depending on the use of particular opioid and the phase of allergic reaction, effects of the treatment on CHS were diverse. While morphine decreased the early and late phases of induction of CHS responses, methadone increased both reactions. In case of the effector phase of CHS, morphine and fentanyl increased both its early and late stages, while methadone decreased the late reaction. Treatment of recipients with opioids had diverse influence on the passive transfer of CHS in these animals.
  
  
  CONCLUSIONS
  Our experiments show that the action of opioids on the immune system is a complex phenomenon dependent on such variables as type of opioid, character of response (humoral versus cellular) and types of cells involved. Here Mf seem to play a significant role.
authors.affiliation: Department of Pain Treatment and Palliative Care, Jagiellonian University Medical College, Sniadeckich 10, PL 31-531 Kraków, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Filipczak-Bryniarska
authors.forename: Bernadeta
authors.initials: B
authors.lastname: Nowak
authors.forename: Emilia
authors.initials: E
authors.lastname: Sikora
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Nazimek
authors.forename: Jarosław
authors.initials: J
authors.lastname: Woroń
authors.forename: Jerzy
authors.initials: J
authors.lastname: Wordliczek
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Bryniarski
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D016207:Cytokines / Q000096:biosynthesis; D005434:Flow Cytometry; D007111:Immunity, Cellular / Q000187:drug effects*; D056724:Immunity, Humoral / Q000187:drug effects*; D008264:Macrophages / Q000502:physiology*; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D016897:Respiratory Burst / Q000187:drug effects
chemical_list: D000701:Analgesics, Opioid; D016207:Cytokines