Claims for Patent: 5,424,208

Summary for Patent: 5,424,208

Title:	Method for isolating cells from tissue with a composition containing collagenase and chymopapin
Abstract:	Proteolytic enzyme compositions and processes for digesting connective tissue are provided. The enzyme compositions include collagenase, which is essentially free of toxins and non-collagen specific components, and chymopapain, which is essentially free of toxins. The enzyme compositions are used for dissociating microvessel cells from connective tissue. Recovered microvessel cells are incorporated into artificial vessel grafts. The composition preferrably contains collagenase having an activity of about 43 nkat/ml to about 51 nkat/ml and chymopapin having an activity of about 0.22 nkat/ml to about 0.44 nkat/ml.
Inventor(s):	Lee; Catherine T. (Laguna Hills, CA), Hornacek; Cynthia (Trabuco Cyn, CA), Dinh; Tan T. (Garden Grove, CA)
Assignee:	Baxter International Inc. (Deerfield, IL)
Application Number:	08/311,383
Patent Claims:	1. A process for isolating viable cells from connective tissue containing viable cells, said process comprising the steps of: providing an enzyme composition comprising an aqueous mixture of collagenase having an activity of about 43 nkat/ml to about 51 nkat/ml and chymopapain having an activity of about 0.22 nkat/ml to about 0.44 nkat/ml, in a physiologically compatible electrolyte solution buffered to a pH of about 7.0 to 7.4, said collagenase being essentially free of toxins and non-collagen active components and said chymopapain being essentially free of toxins; contacting connective tissue containing viable cells with said enzyme composition for a length of time and at a temperature sufficient to hydrolyze said connective tissue without adversely affecting the viability of said cells; and isolating viable cells from the hydrolyzed connective tissue. 2. The process of claim 1 wherein said connective tissue is fatty tissue and said cells are microvessel cells. 3. The process of claim 1 wherein said connective tissue is pancreatic tissue and said cells are pancreatic islet cells. 4. The process of claim 1 wherein said connective tissue is liver tissue and said cells are hepatocytes. 5. The process of claim 1 wherein said electrolyte solution is a phosphate buffered saline solution. 6. The process of claim 1 wherein said electrolyte solution is an aqueous solution of sodium, potassium, magnesium, chloride, acetate, and gluconate ions buffered to a pH of 7.4, and having an osmolarity of 294 mOsmol/L. 7. The process of claim 1 wherein said aqueous solution further comprises about 0.4 wt % human serum albumin.

Details for Patent 5,424,208

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Discure Medical, Llc	CHYMODIACTIN	chymopapain	For Injection	018663	11/10/1982		2013-04-16
Discure Medical, Llc	CHYMODIACTIN	chymopapain	For Injection	018663	08/21/1984		2013-04-16
Smith & Nephew, Inc.	SANTYL	collagenase	Ointment	101995	06/04/1965		2013-04-16