Propagation of human hepatocytes in non-human animals

• US 20020157121A1
• Filed: 08/15/2001
• Published: 10/24/2002
• Est. Priority Date: 11/02/1999
• Status: Active Grant

• Current Assignee: University of Connecticut (State of Connecticut)
• Original Assignee: University of Connecticut (State of Connecticut)
• Inventors: Wu, George Y., Wu, Catherine H.
• Granted Patent: US 6,995,299 B2
• Time in Patent Office: Days
• US Class Current: 800/9
• CPC Class Codes: A01K 2217/05 Animals comprising random inserted nucleic acids (transgenic)
• CPC Class Codes: A01K 67/0271 Chimeric vertebrates, e.g. comprising exogenous cells
• CPC Class Codes: A61K 2035/122 for inducing tolerance or supression of immune responses
• CPC Class Codes: A61K 39/001 Preparations to induce tolerance to non-self, e.g. prior to transplantation
• CPC Class Codes: A61P 1/16 for liver or gallbladder disorders, e.g. hepatoprotective agents, cholagogues, litholytics
• CPC Class Codes: C12N 15/113 Non-coding nucleic acids modulating the expression of genes, e.g. antisense oligonucleotides; Antisense DNA or RNA; Triplex- forming oligonucleotides; Catalytic nucleic acids, e.g. ribozymes; Nucleic acids used in co-suppression or gene silencing when used in plants C12N15/8218
• CPC Class Codes: C12N 5/067 Hepatocytes
• CPC Class Codes: C12N 9/1247 DNA-directed RNA polymerase (2.7.7.6)
• CPC Class Codes: C12N 9/6462 u-Plasminogen activator (3.4.21.73), i.e. urokinase
• CPC Class Codes: C12Y 304/21073 u-Plasminogen activator (3.4.21.73), i.e. urokinase
• CPC Class Codes: G01N 2333/02 Hepadnaviridae, e.g. hepatitis B virus
• CPC Class Codes: G01N 2333/18 Togaviridae; Flaviviridae

Abstract

The present invention relates to the preparation of non-human animals having chimeric livers, whereby some or substantially all of the hepatocytes present are human hepatocytes. It is based, at least in part, on the discovery that rats, tolerized in utero against human hepatocytes, were found to serve as long-term hosts for human hepatocytes introduced post-natally, and the introduced hepatocytes maintained their differentiated phenotype, as evidenced by continued production of human albumin. The present invention further relates to the use of such animals as models of various liver diseases, including viral invention. Such embodiments are based on the discovery that transplanted human hepatocytes in chimeric livers were found to be susceptible to Hepatitis B virus and Hepatitis C virus infection.

Claims

1. A model system for Hepatitis C virus infection in humans, comprising a non-human animal rendered immunologically tolerant to human hepatocytes and subsequently transplanted with human hepatocytes and infected with Hepatitis C virus.

2. The model system of claim 1, where the human hepatocytes are cells of the Huh7 cell line.

3. A method of preparing a host non-human animal to receive a human hepatocyte transplant, comprising:

(i) administering perinatally to the host animal an amount of human hepatocytes, in a form selected from the group consisting of whole cells and a cell lysate, effective in rendering the host animal immunologically tolerant to subsequent exposure to human hepatocytes; and

subsequently

(ii) administering to the host animal an effective amount of a hepatotoxic agent, where the agent is metabolized by liver cells to produce a DNA alkylating agent.

4. The method of claim 3, where the agent is retrorsine.

5. The non-human animal of claim 3 which has further been transplanted with human hepatocytes.