PECAM-1–dependent transmigration does not require the PECAM-1 cytoplasmic domain or cell border localization.

(A) IL-1β–treated RHP and PITC monolayers exposed to anti–PECAM-1 (Houston) or anti–MHC-1 antibodies. (B) IL-1β–treated RHP and PECAM-ΔCD monolayers exposed to anti–PECAM-1 (Houston) antibodies or BSA (100 μg/mL). Similar results were obtained with anti–MHC-1 antibodies instead of BSA (not shown). (C) IL-1β–treated RHP and AAAA monolayers exposed to anti–PECAM-1 (Houston) antibodies or anti–MHC-1 antibodies. Similar results were obtained with BSA instead of anti–MHC-1 antibodies (not shown). Transmigration rates are expressed as the normalized proportion of migrating PMNs compared with “unblocked” TM (set at 1.0) for each cell line. Data represent the mean ± SEM from a minimum of 3 transwells for each condition from 3 separate experiments. (*Significantly different from “unblocked” negative control, P < .05.)