Fig. 4

CD138-neg myeloma cells are more motile in vitro and disseminate better in vivo. a Myeloma cell motility assessed by transwell assay. Percent frequency of CD138+ and CD138− myeloma cells in lower chamber using bulk tumor or FACS sorted and separately tested CD138+ and CD138− subsets (n = 2). b Sorted and labeled CD138+ (red) and CD138− (green) fractions were imaged on collagen coated glass, and cluster sizes were measured by image analysis software. c Analysis of tumor size in the injected (left) tibia 5 weeks after IT injection of FACS-purified CD138 subsets using GFP+ (Vk14451 clone) or GFP− (Vk12598 clone) from ex vivo serum-starved tumors. Analysis of dissemination index (ratio of tumor burden in contralateral tibia over injected tibia) using both clones. Data in d–e are pooled from two experiments for GFP+ clone and one GFP− experiment shown that is representative of the second one as well. Means were analyzed by Mann–Whitney t test. Errors reflect SEM in (a), and SD in (e)