Table 2. Collaborative enhancement binding of anti-muPECAM-1 [125I]-mAb in cellular homogenates of live cells stably expressing muPECAM-1.

	Bmax,fmol mAb/μg total protein added	Kd, nM
Mec13.3 solo	2.3±0.5	9.4±0.2
Mec13.3 paired	6.2±1.0	7.2±0.2
CEPAL, fold change	2.69±0.36*	0.77±0.02*
390 solo	1.25±0.03	5.8±1.1
390 paired	1.62±0.02	5.7±1.9
CEPAL, fold change	1.30±0.02*	0.98±0.22

Binding parameters, Kd and Bmax, are presented as the mean ± SD of three or more independent experiments performed in triplicates. Fold change is presented as a change of paired vs solo, ±SD. (*, P<0.001).