Guinea Pig Sensitization Tests

In three cases of acute human exposure from industrial accidents, symptoms included light-headedness, drowsiness, anxiety and apprehension, and nausea slurred speech and vomiting also occurred in one case. In human patch tests, a 23% solution caused severe irritation and possible sensitization. However, guinea pig sensitization tests did not confirm a potential for sensitization. ... 

When triethanolamine was applied to the skin of rabbits for 72 hours, there was moderate hyperemia, edema, and necrosis. In a guinea pig sensitization test, there was no evidence of sensitization. In the eyes of rabbits, one drop caused moderate, transient injury at 24 hours. ... 

Guinea pig sensitization tests require 6-8 weeks and, therefore, take a long time to complete. 

Coltsfoot demonstrated a weak sensitizing capacity in a guinea pig sensitization test (Zeller et al. 1985). 

Susten, A.S. and MJ. Breitenstein. 1990. Failure of acrolein to produce sensitization in the guinea pig maximization test. Contact Dermat. 22 299-300. 

Sarlo, K., et al., Respiratory allergenicity of detergent enzymes in the guinea pig intratracheal test association with sensitization of occupationally exposed individuals, Fundam. Appl. Toxicol., 39, 44, 1997. 

Certain strains of inbred guinea-pigs can be sensitized to mercuric chloride, and the ability to become sensitized appeared to be transmitted as a dominant characteristic which was not sex-linked [210-212]. By the guinea-pig maximisation test and using a mercuric chloride concentration of 0.1%, a sensitization rate of 8/25 was found and mercuric chloride was graded as a moderate sensitizer [213],... 

FIGURE 15.5. Line chart for guinea pig maximization test for dermal sensitization. 

The guinea pig maximization test (GPMT) is a preferred method for the detection of skin sensitizers. It belongs to the class of adjuvant-tests, where the substance will be applied in Freund s complete adjuvant (FCA). The test is based on the possible induction of an immune response of the skin during an induction period (at least 1 week). This pretreatment of the subject will eventually result in a hypersensitive reaction during a further exposure, the so-called challenging phase. 

S. Frankild, A. Volund, J. E. Wahlberg, and K. E. Andersen. Comparison of the sensitivities of the Buehler test and teh guinea pig maximization test for predictive testing of contact allergey. Acta Derm. Venereol. 80 256-262 (2000). 

There are currently three OECD test guideline methods for test of skin sensitization in animals. These include the Guinea-Pig Maximization Test (GPMT), the Buehler test, and the murine Local Lymph Node Assay (LLNA). 

Bisphenol A causes slight skin and eye irritation. It did not cause contact allergy in a guinea pig maximization test. Furthermore, no cross-reactions were detected when animals sensitized to the diglycidyl ether of bisphenol A were tested with bisphenol A. 

Guinea Pig Maximization Test One of a number of skin tests for screening possible contact allergens. Considered to be a useful model for predicting likely moderate and strong sensitizers in humans. 

The guinea pig intratracheal test has been used to establish the relative potency of different detergent enzymes and establish safe occupational exposure levels. As the name implies, guinea pigs are sensitized by intratracheal exposure and induction of cytophilic antibodies are assessed. Dose responses obtained for new enzymes are compared to a reference enzyme for which safe exposure levels have been established. The relative potency of the new enzyme to this reference is used to establish a safe exposure level for the new enzyme. 

The skin permeability of this chemical is low the log Kp value from the reasoning algorithm is -6.856 and the chemical is known to give a weak response in the guinea pig maximization test, which indicates an equivocal response in mammals. This information leads to the prediction from the software that skin sensitization in humans is doubtful. 

In addition to the above testing protocols, the local lymph node assay (LLNA) has been validated and accepted to assess the skin sensitization potential of chemicals in animals. This does not replace the guinea pig maximization test but is considered to be an equivalent. This in vivo method helps to reduce the number of animals used for contact sensitization activity. This test is based on the principle that sensitizer can induce a primary proliferation of lymphocytes in the lymph node draining the site of chemical application. This provides a quantitative measurement in which the proliferation is proportional to the dose applied. 

In primary irritation tests no or only slight effects were seen at the skin or in the eyes of the treated rabbits respectively [3.205, 3.206]. No skin sensitization occurred in a Guinea pig maximization test [3.203]. 

There are several acceptable ways to evaluate DTH responses in nonclinical species. Of these, the most common are the guinea pig assays used to assess contact sensitization. Both the Magnusson and Kligman model (guinea pig maximization test) and the Buehler model measure the elicitation phase of the hypersensitivity response, though the tests vary in their methods of chemical application and utilization of adjuvants. Most recently, the local lymph node assay has been accepted as a stand alone test for chemical hypersensitivity. This assay is conducted in mice and measures the induction phase of sensitization. In humans, the most common methods to assess delayed hypersensitivity are the patch test (contact sensitivity for diagnostic purposes) and the human repeat insult patch test (contact sensitivity for predictive purposes). Additionally, intradermal... 

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