Comparison of mouse strains using the local lymph node assay

The local lymph node assay (LLNA), as recommended by the Interagency Coordi nating Committee on the Validation of Alternative Methods (ICCVAM), only al lows for the use of CBA mice. The objective of these studies was to begin t o assess the response of chemical sensitizers in the LLNA across six strain s of female mice (C57BL/6, SJL/J, BALB/c, B6C3F1, DBA/2 and CBA). The moder ate sensitizer alpha-hexylcinnamaldehyde (HCA) was chosen as the test chemi cal, while toluene diisocyanate (TDI) and 2,4-dinitrofluorobenzene (DNFB) w ere evaluated at single concentrations as positive controls. Draining lymph node cell proliferation following acetone exposure varied across strains. SJL mice had a significantly higher degree of proliferation with 2111 d.p.m ./2 nodes. The remaining five strains demonstrated responses which ranged f rom 345 to 887 dpm/2 nodes. DBA/2, B6C3F1, BALB/c and CBA mice had essentia lly equal levels of lymph node proliferation following exposure to the thre e chemicals. While C57BL/6 mice gave similar results as CBA mice following DNFB and HCA administration, the LLNA response to TDI was considerably lowe r. SJL mice provided low stimulation indexes (SI) values for all three chem icals evaluated, Regardless of the level of LLNA response, all six mouse st rains identified the sensitization potential of HCA, TDI or DNFB. Based on these studies, DBA/2, B6C3F1 and BALB/c mice are good choices for continued evaluation as additional mouse strains for use in the LLNA. (C) 2000 Elsev ier Science Ireland Ltd. All rights reserved.