Cutter Laboratories, Inc.

Miles Laboratories, Inc.

Bayer Corporation

Michael H Coan

Gautam Mitra

Shohachi Wada

William J Brockway

Cynthia J Galloway

Vivian W Lee

A method of controlling the amount of a biologically active substance binding to a cell surface having both receptors to the substance and receptors for the Fc domain of an antibody that can complex with the substance or other antibodies that can complex with the substance. By exploiting the generally more numerous Fc receptor sites, substance binding can be increased and/or controlled. Method contemplates controlling amounts of substances such as cytokines, hormones, and growth factors that are associated with cells such as monocytes, macrophages, granulocytes, B cells, T cells, and platelets. Method is illustrated using conjugated antibodies to tissue necrosis factor (TNF) to increase the binding of TNF to monocytes.

Cell surface receptor complementation

There is disclosed a method for separating alpha-1-proteinase inhibitor (also known as alpha-1 antitrypsin) from an aqueous solution of plasma proteins, especially from Cohn Effluent II & III and Cohn Effluent I. The method includes the steps of first treating the aqueous solution to lower the concentration of salts therein and, optionally, its alcohol content, contacting the resulting solution with an anion exchange resin having selective affinity for alpha-1-proteinase inhibitor to selectively bind the alpha-1-proteinase inhibitor and allow unwanted plasma proteins to elute through the resin, displacing the alpha-1-proteinase inhibitor from the resin and recovering the same.

Method of preparing alpha-1-proteinase inhibitor

A method is disclosed for separating alpha-1-proteinase inhibitor from a blood plasma fraction particularly from the Cohn fractionation scheme. An aqueous solution of the blood plasma fraction is held at a pH of about 6.5-8.5, and a temperature of about 2.degree.-50.degree. C. for a period of about 0.2-24 hours and then mixed with a poly-condensed polyglycol. The mixture may be held at a temperature of about 2.degree.-10.degree. C. for a period of about 1-24 hours. Next, the pH of the mixture is adjusted to selectively precipitate unwanted proteins from the solution of alpha-1-proteinase inhibitor which is separated from the solution and purified further. The amount of poly-condensed polyglycol and the pH of the mixture are selected accordingly.

Blood-coagulation-promoting products substantially free of thrombin are prepared from human blood plasma by contacting a human blood plasma fraction containing coagulation Factors II, VII, IX and X with an anion exchanger to adsorb the coagulation Factors, which are subsequently eluted from the anion exchanger. The eluate is treated to generate a substance having Factor VIII Inhibitor Bypassing Activity and being substantially free of thrombin, and activated Factor X.

Blood-coagulation-promoting products and methods of preparing them

A method is disclosed for separating alpha-1-proteinase inhibitor from a blood plasma fraction particularly from the Cohn fractionation scheme. An aqueous solution of the blood plasma fraction is held at a pH of about 6.5-8.5, and a temperature of about 2.degree.-50.degree. C. for a period of about 0.2-24 hours and then mixed with a poly-condensed polyglycol in a proportion of about 10-15 parts of polymer per 100 ml of aqueous solution containing the blood plasma fraction. The mixture may be held at a temperature of about 2.degree.-10.degree. C. for a period of about 1-24 hours. Next, the pH of the mixture is adjusted to about 4.6-5.7, to selectively precipitate unwanted proteins from the solution of alpha-1-proteinase inhibitor which is separated from the solution and purified further.

A previously undescribed hydrolytic enzyme has been successfully isolated from human plasma and purified to homogeneity. The enzyme has a molecular weight of about 70,000 daltons, has a Km for the substrate H-D-Phe-Pip-Arg-PNA of about 0.057 mM, a K.sub.I for benzamidine of about 1.1.times.10.sup.-5 M, is bindable to and elutable from insoluble barium salts, is inhibited by antithrombin III, especially in the presence of heparin, and, in vitro, has been found to activate and degrade human Factor VIII, activate human Factor V, and inhibit platelet aggregation induced by ADP, epinephrine, or collagen, thus providing a substance useful for antithrombotic studies.

Growing community of inventors

El Cerrito, CA, United States of America

Michael H Coan