Figure 2.

l-selectin is shed after in vitro CD4 ligation. Enriched huCD4⁺ T cells from mCD4KO/huCD4tg mice were incubated in vitro with or without anti-huCD4 mAb as described in Materials and Methods. After 4 h cells were harvested and analyzed for l-selectin expression by confocal microscopy. Samples were double stained for CD3 (shown in green) and l-selectin (shown in red). (A) CD3 expression and l-selectin expression on untreated and anti-huCD4 mAb-treated cells that had and had not been made permeable with saponin (0.1%). (B) To control for sufficient permeability, cells were stained with rhodamine-conjugated phalloidin. Results are representative of at least three experiments.