Skin Sensitization Test

This test examines the potential of a chemical to cause contact dermatitis, which is a type of immune response known as a delayed hypersensitivity reaction. Traditionally, 

Essentials of Toxic Chemical Risk Science and Society 

In recent years, the mouse local lymph node assay (LLNA) has been approved as an alternative to the guinea pig test. It is based on the proliferation of lymphocytes (a type of immune cell) in lymph nodes draining the site of contact with the chemical. In the LLNA, the substance is applied to the mouse s ear on days 1-3 of the test but withheld on days 4 and 5 to give the immune system a chance to respond. On day 6, the mouse is injected in its tail vein with a small amount of a radioactive DNA base such as H-thymidine (tritiated thymidine) to label newly formed immune cells. The mouse is sacrificed, its auricular lymph nodes (located near the ears) are cut out, and their radioactivity is measured. Increased radioactivity in the lymph nodes of treated animals compared with controls indicates that the test chemical sensitizes the immune system and can cause contact dermatitis. The LLNA is more objective than the traditional guinea pig test because the amount of immune cell proliferation can be determined as a function of dose. 

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Di-w-octylphthalate was negative in a skin sensitization test in guinea pigs (Eastman Kodak Company 1978). No further details were provided in this summary report. 

D. A. Basketter, G. F. Gerberick, I. Kimber, and S. E. Loveless. The local lymph node assay A viable alternative to currently accepted skin sensitization tests. Food Chem. Toxicol. 34 985-997 (1996). 

Applied to the skin of rats and rabbits, the undiluted liquid produced skin irritation, with subsequent degeneration of the epidermis skin sensitization tests in guinea pigs were negative. 

Immunotoxicity. There are currently no data on the effects of 2-hexanone on the human immune system via any route of exposure. Animal data included an inhalation study in which there was a 40% decrease in peripheral white blood cells in rats exposed to 2-hexanone (Katz et al. 1980). In addition, 2,5-hexanedione, a metabolite of 2-hexanone, was shown to adversely affect lymphoid organs of the immune system in rats and to cause impairment of immunity in mice (Upreti and Shanker 1987). Immunological assessments, including analysis of peripheral blood components and effects on lymphoid tissue, conducted as part of intermediate-or chronic-duration studies and skin sensitization tests would be useful in developing a dose-response relationship and assessing the potential risk to chronically exposed persons in the vicinity of hazardous waste sites or to exposed workers. 

In general, all dermatologiccil preparations must be subjected to skin sensitization tests. 

Skin sensitization tests assess the ability of chemicals to affect the immune system, such that a second contact causes a more severe reaction than the first. The antigen involved is presumed to be formed in the bonding of the chemical to body proteins. The antibodies that form to this ligand-protein complex give rise to an allergic reaction with subsequent exposure. 

Kimber I, et al. (2001) Skin sensitization testing in potency and risk assessment. Toxicological Sciences 59(2) 198-208. 

Allergies to resorcinol have been widely described. It is therefore wise to do a skin sensitivity test behind the ear 8 days before a resorcinol peel. Any contact with resorcinol can sensitize the patient (or the physician) to it, so the test... 

Ashikaga T, Yoshida Y, Hirota M, Yoneyama K, Itagaki H, Sakaguchi H, Miyazawa M, Ito Y, Suzuki H, Toyoda H (2006) Development of an in vitro skin sensitization test using human cell lines the human cell line activation test (h-CLAT). I. Optimization oftheh-CLAT protocol. Toxicol In Vitro 20 767-773... 

Natsch A, Emter R, Ellis G (2009) Filling the concept with data integrating data from different in vitro and in silico assays on skin sensitizers to explore the battery approach for animal-free skin sensitization testing. Toxicol Sci 107 106-121... 

Gildea LA, Ryan CA, Foertsch LM, Kennedy JM, Dearman RJ, Kimber I, Gerberick GF. Identification of gene expression changes induced by chemical allergens in dendritic cells opportunities for skin sensitization testing. J Invest Dermatol 2006 126 1813-1822. 

S. Kitajima, J. Momma, T. Inoue, Reactivities of the skin-sensitization test in guinea pig (GPMT) as a function of three parameters induction doses (MID), challenge doses (SCD), and direct exposures (DED), Ann. N. Y. Acad. Sci., 919 312-314 (2000). 

In guinea pig skin sensitization test, with observations at 24 and 48 h after application, no... 

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