title: Cross-reactivity between methylisothiazolinone, octylisothiazolinone and benzisothiazolinone using a modified local lymph node assay.
abstract: BACKGROUND
  In the light of the exceptionally high rates of contact allergy to the preservative methylisothiazolinone (MI), information about cross-reactivity between MI, octylisothiazolinone (OIT) and benzisothiazolinone (BIT) is needed.
  
  
  OBJECTIVE
  To study cross-reactivity between MI and OIT, and between MI and BIT.
  
  
  METHODS
  Immune responses to MI, OIT and BIT were studied in vehicle and MI-sensitized female CBA mice by a modified local lymph node assay. The inflammatory response was measured by ear thickness, cell proliferation of CD4+and CD8+T cells, and CD19+B cells in the auricular draining lymph nodes.
  
  
  RESULTS
  MI induced significant, strong, concentration-dependent immune responses in the draining lymph nodes following a sensitization phase of three consecutive days. Groups of MI-sensitized mice were challenged on day 23 with 0·4% MI, 0·7% OIT and 1·9% BIT - concentrations corresponding to their individual EC3 values. No statistically significant difference in proliferation of CD4+and CD8+T cells was observed between mice challenged with MI compared with mice challenged with BIT and OIT.
  
  
  CONCLUSIONS
  The data indicate cross-reactivity between MI, OIT and BIT, when the potency of the chemical was taken into account in choice of challenge concentration. This means that MI-sensitized individuals may react to OIT and BIT if exposed to sufficient concentrations.
authors.affiliation: National Allergy Research Centre, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Kildegårds Allé, 2900 Hellerup, Denmark.
authors.forename: J F
authors.initials: JF
authors.lastname: Schwensen
authors.affiliation: Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Menné Bonefeld
authors.affiliation: Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Kildegårds Allé, 2900 Hellerup, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Zachariae
authors.affiliation: Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Agerbeck
authors.affiliation: Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: T H
authors.initials: TH
authors.lastname: Petersen
authors.affiliation: Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: C
authors.initials: C
authors.lastname: Geisler
authors.affiliation: Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark.
authors.forename: U E
authors.initials: UE
authors.lastname: Bollmann
authors.affiliation: Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Bester
authors.affiliation: National Allergy Research Centre, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Kildegårds Allé, 2900 Hellerup, Denmark.
authors.forename: J D
authors.initials: JD
authors.lastname: Johansen
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D004202:Disinfectants / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004431:Ear, External / Q000187:drug effects; D005260:Female; D007111:Immunity, Cellular / Q000502:physiology; D023441:Local Lymph Node Assay; D008198:Lymph Nodes / Q000187:drug effects* / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008808:Mice, Inbred CBA; D013844:Thiazoles / Q000008:administration & dosage / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D004202:Disinfectants; D013844:Thiazoles; C512915:isothiazolidinone; C011506:2-methyl-4-isothiazolin-3-one; C015699:1,2-benzisothiazoline-3-one