Proteinase inhibitors TOPICAL

A systematic view on the topic of complexation and complexes in the literature shows a great number of important research results. This expanding field covers studies of various systems, including antibody-antigen complexes, proteinase-inhibitor complexes, lipid-based delivery vehicles, metal complexes with DNA base pair, and aqua ligand in the coordination sphere of metal, The metal-modified structures are dominated by these metal-base interactions. However, the structural role of the water molecules in the complexes is quite apparent, as suggested by crystallographic studies.f ... 

In addition to topical antimycotic therapy, systemic NSAIDs and topical atropine sulfate are used to the control pain and ameliorate the effects of anterior segment injury associated with the iridocyclitis that inevitably accompanies ker-atomycosis. Topical proteinase inhibitor therapy is of significant clinical benefit in controlling stromal breakdown and, since potentially pathogenic bacteria contaminate most mycotic lesions, concurrent broad-spectrum, topical antibacterial agents should be used. 

Clearly, inhibition of enzymatic degradation is fundamental to the medical management of corneal ulceration. The ocular surface is openly accessible to topical proteinase inhibitor therapy, administered by direct instillation or via a sub-palpebral lavage system. Inhibitor therapy is of most value in acute frank ulceration where it is used in conjunction with antimicrobial agents, but it may also be useful in promoting healing of refractory ulcers and chronic superficial erosions. Antiproteinases may be used prophylactically along with antibiotics in superficial injury where ulceration threatens. 

Isologous or homologous plasma or serum can be harvested and used topically. Plasma or serum may be stored at 0-4°C for up to 36 h. It should be divided into aliquots before storage and returned to physiological temperature before being mstilled into the eye. Serum or plasma can be used in combination with EDTA and acetylcysteine to provide a broader spectrum proteinase inhibitor formulation. 

Such inhibitors might bind intestinal proteinases and thus be of concern (Richardson, 1981). Less is known about stability of various lectins (Jaff, 1980). Some lectins appear to be less heat-stable, but some reports suggest that others may survive food processing (Nachbar and Oppenheim, 1980 Sgarbieri and Whitaker, 1982 Thompson et al., 1983). Other topics related to stability of proteinase inhibitors are discussed elsewhere in this volume by Gallaher and Schneeman and by Pearce et al. 

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