Fig. 6.

Transfection with NSIST cDNA increases mAb CS-56 immunolabeling to COS cell membrane fractions. COS cells were transfected with NSIST cDNA or with an irrelevant cDNA (LNGFR). Cell membranes were separated by SDS-PAGE on a 5–15% gradient gel, transferred to nitrocellulose, and probed with anti-CS mAb CS-56. A broad band spanning ∼60–200 kDa is prominent in the NSIST-transfected sample, but only weakly visible in membranes from the nontransfected cells. Some additional bands are also specifically labeled in the NSIST lane. There was no labeling when irrelevant IgM was used as the primary antibody (data not shown).