Comparison of TEM of PLP-specific T cells in the 2 bEnd cell lines. TEM of PLP-specific T cells was compared across bEndI1/2.1 (A) or bEndI1.1 (B) re-expressing wild-type ICAM-1 or ICAM-1 mutants. One representative experiment, performed as described in Figure 2A, directly compared TEM of SJLB.PLP3 across unstimulated and TNF-α-stimulated bEndI1/2.1 (A) or bEndI1.1 (B) with their TEM across the respective daughter endothelioma lines transduced with wild-type (wt) ICAM-1 or the ICAM-1 mutants M1, M2, M3, M4, and M5. The ICAM-1 mutants M2, M3, and M4 harboring mutations of tyrosines to phenylalanines re-established TEM of PLP-specific T cells across unstimulated and TNF-α-stimulated bEnd I1/2.1 and bEndI1.1 comparable to wild-type ICAM-1 (panels A, B). In contrast, the cytoplasmic deletion mutants M1 and M5, although restoring some TEM of PLP-specific T cells across bEnd I1/2.1 and bEndI1.1, were unable to reconstitute TEM to wild-type levels. Bars represent mean ± SD (n = 3); significant differences of wt versus mutant are marked as follows: ^*P < .05, significant; ^**P < .01, very significant; ^***P < .001, extremely significant.