title: Regulation of histamine synthesis in mouse CD4+ and CD8+ T lymphocytes.
abstract: OBJECTIVE
  Previously, we have shown that mouse T lymphocytes produce de novo histamine in response to mitogens. The aim of this study was to examine which subsets of T cells produce histamine and to clarify the regulatory mechanisms of the reaction.
  
  
  METHODS
  CD4+ and CD8+ T lymphocytes were separated from spleen cells of mast cell-deficient WBB6/F1 (W/Wv) mice using anti-CD4- and anti-CD8-coupled magnetic beads, respectively.
  
  
  RESULTS
  Both CD4+ T cells and CD8+ T cells released histamine when treated with Con A as a function of incubation time. Since histamine bound to each cell fraction was negligible before and after the treatment, it is highly likely that this indicates de novo synthesis of histamine by these cells. Granulocyte/macrophage colony-stimulating factor (GM-CSF) or IL-3 strongly enhanced the Con A-induced histamine formation. IL-1-alpha also potentiated the Con A-dependent histamine production. Dexamethasone, but not progesterone, significantly inhibited the Con A-dependent as well as Con A-independent histamine synthesis. Both GM-CSF and IL-3 caused a marked accumulation of histidine decarboxylase (HDC, EC 4.11.22) mRNAs in the cells.
  
  
  CONCLUSIONS
  These results suggest that GM-CSF and IL-3 enhance histamine synthesis in CD4+ T cells and CD8+ T cells.
authors.affiliation: Bioscience Center, Nagoya University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kubo
authors.forename: K
authors.initials: K
authors.lastname: Nakano
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D016207:Cytokines / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D005938:Glucocorticoids / Q000494:pharmacology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006632:Histamine / Q000096:biosynthesis*; D006640:Histidine Decarboxylase / Q000096:biosynthesis; D007371:Interferon-gamma / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000166:cytology / Q000378:metabolism
chemical_list: D016207:Cytokines; D005938:Glucocorticoids; D012333:RNA, Messenger; D003208:Concanavalin A; D003907:Dexamethasone; D006632:Histamine; D007371:Interferon-gamma; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006640:Histidine Decarboxylase