SDS Page gels showing Factor Xa cleavage of the fusion proteins. a) IFABP-A 1–40. Lane 1, Ni-NTA column purified fusion protein. Lane 2, after purification with size exclusion chromatography and prior to cleavage with Factor Xa, Lane 3, after cleavage with Factor Xa. Lane 4, molecular weight markers. b) IFABP-A 1–42. Lane 1, Ni-NTA column purified fusion protein. Lane 2, after purification with size exclusion chromatography and prior to cleavage with Factor Xa, Lane 3, after cleavage with Factor Xa. Lane 4, molecular weight markers.