APPLICATION OF NOVEL MONOCLONAL-ANTIBODIES IN THE PURIFICATION, QUANTIFICATION, AND IMMUNOHISTOLOGICAL LOCALIZATION OF THE PROTEINASE-INHIBITOR ALPHA-2-MACROGLOBULIN

Monoclonal antibodies (moAbs) recognizing human α2-macroglobulin (hMG), a broad-spectrum proteinase inhibitor present in plasma and the interstitial fluid, were developed and characterized. hMG-specific moAbs were found useful (1) to purify the inhibitor molecule via one-step immunoaffinity chromatography; (2) to identify hMG by immunochemical methods (i.e., immunoblotting) in complex biological samples; (3) to quantify hMG by means of a moAb-based enzyme immunoassay; and (4) to localize the antigen by immunohistological methods. By immunofluorescence studies on normal human skin we localized hMG to the epidermo-dermal junction, indicating that this proteinase inhibitor may play an important role in the physiology of the human integument. Taken together, these antibodies appear as powerful tools for the purification of hMG and for immunochemical and immunohistological studies on this molecule.