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Local Lymph Node Assay

Table of Contents

1. Test Submission
   1. Cover Letter
   2. Submission
2. Appendices
   1. Local Lymph Node Assay Bibliography
   2. List of Chemicals
      1. Chemicals Tested in Local Lymph Node Assay
      2. Discordant Results Between Local Lymph Node Assay and Guinea Pig or Human Test Methods
      3. Disintegrations Per Minute Data and Stimulation Indices for Discordant Results
   3. Key Local Lymph Node Assay Papers
   4. Sample Local Lymph Node Assay Protocol
   5. ICCVAM Local Lymph Node Assay Test Submission Guidelines

APPENDIX B: Table 2

Discordant Results Between the Local Lymph Node Assay and Guinea Pig or Human Test Methods

^#Positive results based on EC classification threshold
^*Result obtained in a non-standard guinea pig test
^**Ref Benzocaine paper

¹Significant human contact allergen that should be positive in a predictive test.
²Very, difficult sensitiser in predictive tests is only a human allergen under unique conditions of exposure.
³A false positive in the LLNA.
⁴Likely to be a true positive based on both the LLNA and structure activity considerations; the guinea pig data are from a nonstandard version of the GPMT that omits the patch induction phase.
⁵Acrylate allergy is a complex subject, with many acrylate derivatives being suspected of giving rise at least to some degree of clinical disease.
⁶A well-described contact allergen in medicaments, but which was much weaker than Kanamycin in a human predictive test.
⁷A very weak allergen in human predictive tests (equivalent to paraben) and which is thus an unexpected positive in the LLNA.
⁸Whilst this substance was positive in the GPMT (which involves injection), its size and charge will result in extremely poor skin penetration, such that it is unlikely to cause allergic contact dermatitis. Thus, the LLNA result is likely to be the more meaningful.
⁹False negative in the LLNA.
¹⁰A false negative probably due to poor skin penetration engendered by the size of the compound, its very high log P, and the presence of a charged group.
¹¹This substance is a rare allergen except in specific disease states; it is not positive in predictive assays except the human maximization test.
¹²Unexpected negative in both the LLNA and guinea pig tests.
¹³Although a clear positive in the GPMT, this substance was negative in both the LLNA and on the basis of substantial human exposure experience, suggesting it is the LLNA result which is correct.