Complex sentence: CRM-197 is a non-toxic mutant of diphtheria toxin, manufactured as a recombinant protein and used as a carrier protein for polysaccharides and haptens to make them immunogenic.
Split into simpler sentences: CRM-197 is a non-toxic mutant of diphtheria toxin, manufactured as a recombinant protein. The product is used as a carrier protein for polysaccharides and haptens to make them immunogenic.