Human kappa light chain levels are significantly higher in animals bearing tumors expressing soluble syndecan-1.

Sera from animals were collected at 1, 4, 6, and 8 weeks after injection of tumor cells and analyzed for kappa light chain by ELISA. Data include all animals that were injected with tumor cells (13 neo, 14 Syn-1, and 15 sSyn-1) and shown are means from duplicate samples ± SD from a single ELISA assay. The sSyn-1 results reflect use of both the sSyn-1.10 and sSyn-1.2 clones that gave similar results in vivo. At week 8, P < .0001 for neo versus sSyn-1 and Syn-1 versus sSyn-1.