Abstract
The human Cell Line Activation Test (h-CLAT) is an in vitro skin sensitization method based on augmentation of CD86 and CD54 expression in THP-1 cells (human monocytic leukemia cell line). In our previous Japanese inter-laboratory study, we reported that the transferability and reproducibility of the h-CLATis basically good. The aim of this study was to define the criteria for selecting appropriate THP-1 cells inthe h-CLAT. In this study, new THP-1 cell lots were obtained from three cell banks: one in America,Europe and Japan. Using these three lots plus the cell lot we had previously used and obtained from ATCCwe investigated the CD86/CD54 expression following exposure to two allergens (DNCB and Ni) and onenon-allergen (SLS). Compared with the previous ATCC lot, two new lots showed similar results. Mean-while, the third new lot showed distinctly different results in cell viability and CD86/CD54 augmentationinduced by Ni compared to the other three lots. These results showed that the variability of cellular responses in the THP-1 cells depended on the cell source. In conducting the h-CLAT, it would be importantto select appropriate THP-1 cells to predict correctly the skin sensitization potential.
