The current invention involves a series of fully recombinant multimerized forms of immunoglobulin Fc which thereby present polyvalent immunoglobulin Fc to immune cell receptors. The fusion proteins exist as both homodimeric and highly ordered multimeric fractions, termed stradomers. In comparison to the homodimeric fraction, purified multimeric stradomers have higher affinity for Fc Rs with slower dissociation and are useful in the treatment and prevention of disease. The current invention demonstrates that directly linking IgGI Fc regions to multimerization domains leads to enhanced multimerization and biological activity.