Purification and characterization of a monoclonal T-cell suppressor factor specific for poly(LGlu60LAla30LTyr10)

A monoclonal T-cell-derived suppressor factor specific for the terpolymer poly(LGlu60LAla30LTyr10) produced by the T-cell hybridoma 258 C4.4, was purified to homogeneity. This was accomplished by fractionation of the culture medium by using a combination of affinity chromatography and reverse-phase and ion-exchange high-performance liquid chromatography. The purified factor is composed of a single Mr 24,000 polypeptide chain, and the homogeneous protein maintains the ability to suppress antibody and T-cell proliferative responses to poly(LGlu60LAla30LTyr10) specifically. The specific activity of pure suppressor factor is calculated to be 8 X 10(7) units/micrograms.