Non-Simian Cells for Growth of Porcine Reproductive and Respiratory Syndrome (PRRS) Virus

Abstract

Disclosed are compositions and methods relating to growth of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) using non-simian cells. In a particular example, porcine alveolar macrophage cells are described as having a capability of supporting infectivity and reproduction by PRRSV. Cells and cell lines of the invention are disclosed in connection with applications relating to PRRS disease, including vaccine technologies.

1 . An isolated non-simian cell capable of reproducing the PRRS virus, wherein the non-simian cell is obtained from an individual animal and cultured for at least 5 passages. 
     
     
         2 . An isolated porcine fetal lung cell capable of infection by and/or reproducing the PRRS virus. 
     
     
         3 . The cell of  claim 2  which is an alveolar macrophage cell. 
     
     
         4 . The cell of  claim 2  which is propagated in culture for at least 5 passages. 
     
     
         5 . The cell of  claim 2  which is propagated in culture for at least 10, 20, and/or 50 passages. 
     
     
         6 . An isolated primary cell or cell population obtained from a lung of a porcine fetus. 
     
     
         7 . The cell or cell population of  claim 6  wherein the fetus is from about 30 to about 90 days of gestational age. 
     
     
         8 . The cell or cell population of  claim 6  wherein said cell is an alveolar macrophage or said cell population comprises at least one alveolar macrophage cell. 
     
     
         9 . The cell of  claim 1  wherein said cell is represented by a cell designated as ZMAC-1 or a deposit with the American Type Culture Collection designated as ATCC Patent Deposit No. PTA-8764 or derived therefrom. 
     
     
         10 . An immortalized cell variant or derivative of the cell of  claim 1 . 
     
     
         11 . A method of generating progeny of a PRRS virus comprising:
 a) providing an isolated or purified non-simian cell capable of replicating a PRRS virus, wherein said non-simian cell is cultured for at least 5 passages;   b) exposing said non-simian cell to said PRRS virus; and   c) allowing the PRRS virus to replicate in the cell;   thereby generating progeny of a PRRS virus.   
     
     
         12 . The method of  claim 11  wherein said non-simian cell is obtained from an individual animal. 
     
     
         13 . A method of producing a PRRS vaccine, comprising providing a modified-live virus (MLV) strain of PRRSV, and growing said MLV strain in an isolated or purified non-simian cell capable of replicating said PRRSV MLV strain. 
     
     
         14 . The method of  claim 13 , wherein said non-simian cell is a porcine alveolar macrophage cell. 
     
     
         15 . The method of  claim 13 , wherein said non-simian cell is a porcine alveolar macrophage primary cell, cell population, variant or derivative thereof. 
     
     
         16 . The method of  claim 11  wherein the cell is selected from the group consisting of ZMAC and FBAL-A. 
     
     
         17 . The method of  claim 12  wherein the cell is selected from the group consisting of ZMAC and FBAL-A. 
     
     
         18 . The method of  claim 11  wherein the non-simian cell is represented by a cell designated as ZMAC-1 or a deposit with the American Type Culture Collection designated as ATCC Patent Deposit No. PTA-8764 or derived therefrom. 
     
     
         19 . A cell or cell line designated as ZMAC-1 or represented by a deposit with the American Type Culture Collection designated as ATCC Patent Deposit No. PTA-8764 or derived therefrom, or a cell or cell line designated as FBAL-A. 
     
     
         20 . (canceled) 
     
     
         21 . A method of isolating a cell from a porcine fetal lung comprising providing a porcine fetal subject; obtaining a cell-containing bronchoalveolar lavage sample from said subject; and separating a cellular component from said sample; thereby isolating said cell. 
     
     
         22 . The method of  claim 21  wherein said cell-containing sample is a bronchoalveolar lavage sample. 
     
     
         23 . The method of  claim 21  wherein said sample is an excised tissue sample which is optionally processed by maceration and/or homogenization. 
     
     
         24 . A method of growing a virus, comprising: (a) isolating a cell from a porcine fetal lung; (b) culturing said cell; and (c) contacting said cell with said virus so as to allow viral replication; thereby growing the virus. 
     
     
         25 . The method of  claim 24  wherein said virus is a PRRS virus. 
     
     
         26 . The method of  claim 24  wherein said culturing comprises passaging said cell for at least 5 passages and/or growing said cell for at least 10 days of continuous culture. 
     
     
         27 . The method of  claim 24  wherein said isolating is according to  claim 21 . 
     
     
         28 . A composition comprising a virus grown in the cell of  claim 1  or grown in an immortalized cell variant or derivative of said cell. 
     
     
         29 . The composition of  claim 28  wherein the virus is PRRS virus. 
     
     
         30 . The method of  claim 11 , further comprising contacting said cell with a growth factor composition. 
     
     
         31 . The method of  claim 30  wherein said growth factor composition comprises macrophage colony stimulating factor (MCSF) or granulocyte-macrophage colony stimulating factor (GMCSF).