title: Local lymph node assay (LLNA): comparison of different protocols by testing skin-sensitizing epoxy resin system components.
abstract: Thirteen epoxy resin system components were tested in the LLNA with regard to their sensitizing potency. Lymph node stimulation was quantified not only by measuring the incorporation of [3H]-thymidine into the ear lymph nodes but also the counts of cells recovered from these organs. Equivalent figures were obtained with both endpoints used for the evaluation of lymph node cell proliferation if the reference stimulation indices were adjusted. When dissolved in acetone, all test substances showed skin-sensitizing potential, mainly on the boundary between "strong" and "moderate" according to common potency evaluation schemes. Replacing acetone with acetone/olive oil (4:1) as a vehicle for four selected test items, resulted in considerably lower estimated concentrations for sensitization induction. The challenges in comparing the results obtained by different LLNA variations are discussed.
authors.affiliation: BASF SE, Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany.
authors.forename: Armin O
authors.initials: AO
authors.lastname: Gamer
authors.forename: Eberhard
authors.initials: E
authors.lastname: Nies
authors.forename: Hans-Werner
authors.initials: HW
authors.lastname: Vohr
mesh_terms: D000287:Administration, Topical; D000485:Allergens / Q000008:administration & dosage / Q000633:toxicity*; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D054644:Ear Auricle / Q000187:drug effects; D004853:Epoxy Resins / Q000008:administration & dosage / Q000633:toxicity*; D005189:False Positive Reactions; D005260:Female; D007114:Immunization / Q000379:methods*; D008198:Lymph Nodes / Q000187:drug effects*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D023421:Models, Animal; D010328:Patch Tests / Q000379:methods; D028223:Pinus; D011849:Radioactive Tracers; D018709:Statistics, Nonparametric; D018675:Toxicity Tests / Q000379:methods*
chemical_list: D000485:Allergens; D004853:Epoxy Resins; D011849:Radioactive Tracers