Involvement of the three inter-alpha-trypsin inhibitor (ITI) heavy chains in each member of the serum ITI family.

Partial cDNAs coding for each of the three human inter-alpha-trypsin inhibitor (ITI) heavy chains were expressed in a bacterial plasmid system and rabbits were immunised with the fusion peptides obtained. Despite the strong sequence homology of these chains, the antisera turned out to be highly specific in the analysis of corresponding mRNA translation products or partially digested serum ITI. Besides classical serum ITI members, their use in Western blotting made it possible to evidence an H3-related ITI form and a low-amount H1-related HC/bikunin component. The relative levels of ITI family members was further studied in baboon and foetal calf sera.