The h-CLAT Method

The h-CLAT method, which was developed in Japan, is based on the augmentation of surface marker CD86 and/or CD54 expression in THP-1 cells. After 24 h treatment with a test chemical, the expression of CD86 and CD54 of THP-1 cells is analysed using flow cytometry. The main prerequisite for the method is the solubility of the test chemical in the culture medium. Many publications have shown the usefulness of the h-CLAT method for the prediction of the skin sensitization potential of targeted chemicals. Moreover, after formal validation of the h-CLAT method by EURL ECVAM, the OECD has recently adopted a new TG No. 442E for the h-CLAT method[1]. Because h-CLAT will not be sufficient as a stand-alone method to cover the endpoint of skin sensitization, data generated with the h-CLAT method should be considered in the context of integrated approaches. The test developers strongly believe that the h-CLAT method will play an important role in in vitro skin sensitization testing.