Figure 1.
Sequence alignments and surface plasmon resonance analysis of the affinity of cCD58 for CD2. (A) Interdomain sequence alignments for the CD2-subset of the IgSF: human CD2 (hCD2 European Molecular Biology Laboratory accession number M16445), rat CD2 (rCD2; X05111), SLAM (U33017), 2B4 (L19057), Ly-9 (M84412), rat CD48 (rCD48; M37766), and CD58 (Y00636). The arrow indicates the position in the CD58 sequence at which the sequence for domain 2 was substituted with that of rat sCD2 to generate cCD58. (B) Human sCD2 was injected over BIAcore2000 sensor surfaces to which cCD58 (Left), sCD58 (Right), or a control protein (OX54; not shown) had been immobilized. The background response observed with injection of sCD2 over the control flow-cell was subtracted to give the amount of sCD2 bound. The lines drawn are a fit of the Langmuir 1:1 binding isotherm to the data. The insets show Scatchard plots of the data with linear fits. Both approaches gave the same Kd values.