title: Inhibitory effects of progesterone differ in dendritic cells from female and male rodents.
abstract: BACKGROUND
  Steroid hormones, such as progesterone, are known to have immunomodulatory effects. Our research group previously reported direct effects of progesterone on dendritic cells (DCs) from female rodents. Primarily affecting mature DC function, progesterone effects included inhibition of proinflammatory cytokine secretion, downregulation of cell surface marker (major histocompatibility complex class II, CD80) expression, and decreased T-cell proliferative capacity, and were likely mediated through progesterone receptor (PR) because the PR antagonist RU486 reversed these effects.
  
  
  OBJECTIVE
  The goal of this study was to assess differences in response to progesterone by DCs from female and male rodents.
  
  
  METHODS
  Using real-time reverse-transcriptase polymerase chain reaction, transcriptional expression of steroid hormone receptors was measured in immature bone marrow-derived DCs (BMDCs) from male and female rats. Expression of steroid hormone receptor protein was also assessed in these cells using flow cytometry and fluorescence microscopy. To evaluate functional differences between BMDCs from female and male rats in response to the steroid hormone progesterone, levels of secreted cytokines were measured using enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Higher numbers of immature BMDCs from males expressed glucocorticoid receptor (GR) and androgen receptor (AR) proteins compared with females (males vs females, mean [SD]: GR = 68.75 [7.27] vs 43.61 [13.97], P = NS; AR = 75.99 [15.38] vs 8.25 [1.88], P = 0.002), whereas higher numbers of immature BMDCs from females expressed PR protein compared with males (females vs males: PR = 74.19 [12.11] vs 14.14 [4.55], P = 0.043). These differences were not found at the level of transcription (females vs males: GR = 0.088 vs 0.073, P = NS; AR = 0.076 vs 0.069, P = NS; PR = 0.075 vs 0.065, P = NS). Compared with those from females, mature BMDCs from males produced higher quantities of cytokines (tumor necrosis factor-alpha [TNF-alpha], interleukin [IL]-1beta, IL-10) (females vs males: TNF-alpha = 920.0 [79.25] vs 1100.61 [107.97], P = NS; IL-1beta = 146.60 [38.04] vs 191.10 [10.47], P = NS; IL-10 = 167.25 [4.50] vs 206.15 [23.48], P = NS). Conversely, BMDCs from females were more sensitive to progesterone, as indicated by a more dramatic reduction in proinflammatory cytokine secretion (females vs males, highest concentration of progesterone: TNF-alpha = 268.94 [28.59] vs 589.91 [100.98], P = 0.04; IL-1beta = 119.50 [10.32] vs 154.35 [6.22], P = NS).
  
  
  CONCLUSIONS
  These findings suggest that progesterone effects on DCs in rodents may be more pronounced in females than in males, and this is likely due to differences in PR protein expression. Our observations may help elucidate disparities in the incidence and severity of autoimmune disorders between females and males, and the role specific steroid hormones play in regulating immune responses.
authors.affiliation: Section on Neuroendocrine Immunology & Behavior, National Institute of Mental Health/NIH, Bethesda, Maryland 20892, USA.
authors.forename: Cherié L
authors.initials: CL
authors.lastname: Butts
authors.forename: Eve
authors.initials: E
authors.lastname: Bowers
authors.forename: J Cash
authors.initials: JC
authors.lastname: Horn
authors.forename: Shetha A
authors.initials: SA
authors.lastname: Shukair
authors.forename: Elena
authors.initials: E
authors.lastname: Belyavskaya
authors.forename: Leonardo
authors.initials: L
authors.lastname: Tonelli
authors.forename: Esther M
authors.initials: EM
authors.lastname: Sternberg
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects*; D000818:Animals; D000941:Antigens / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002469:Cell Separation; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D016753:Interleukin-10 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D008297:Male; D011374:Progesterone / Q000494:pharmacology*; D011372:Progestins / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D011980:Receptors, Progesterone / Q000187:drug effects / Q000378:metabolism; D012727:Sex Characteristics; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000941:Antigens; D053583:Interleukin-1beta; D011372:Progestins; D012333:RNA, Messenger; D011980:Receptors, Progesterone; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D011374:Progesterone