Methods for assessing the purity of a mesenchymal stem cells preparation

Abstract

The present invention relates to a method for assessing, evaluating and/monitoring the purity of a mesenchymal stem cells preparation, in particular of an adipose stem cells preparation, comprising measuring the expression level of at least one growth factor.

1 - 14 . (canceled) 
     
     
         15 . An in vitro method for assessing, evaluating and/or monitoring the purity of a cell preparation comprising mesenchymal stem cells (MSC), wherein said method comprises measuring the expression level of at least one growth factor expressed by said cell preparation, wherein said at least one growth factor is SDF-1α and/or VEGF. 
     
     
         16 . The in vitro method according to  claim 15 , wherein said method further comprises comparing the measured expression level with a reference expression level. 
     
     
         17 . The in vitro method according to  claim 15 , wherein said mesenchymal stem cells are isolated from tissues selected from the group comprising adipose tissue, bone marrow, umbilical cord blood, amniotic fluid, Wharton's jelly, placenta, peripheral blood, fallopian tube, corneal stroma, lung, muscle and fetal liver. 
     
     
         18 . The in vitro method according to  claim 15 , wherein said mesenchymal stem cells are adipose stem cells (ASC). 
     
     
         19 . The in vitro method according to  claim 15 , wherein said expression level is assessed at the protein level, preferably by the detection and/or quantification of said at least one growth factor secreted in the cell culture supernatant. 
     
     
         20 . The in vitro method according to  claim 15 , wherein said expression level is assessed at the RNA level, preferably by RT-PCR, RT-qPCR, Northern Blot and/or hybridization techniques. 
     
     
         21 . The in vitro method according to  claim 15 , wherein said cell preparation is substantially pure when the SDF-1α expression level is of at most 100 pg/ml, preferably of at most 50, 40, 30, 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 pg/ml. 
     
     
         22 . The in vitro method according to  claim 15 , wherein said cell preparation is substantially pure when the SDF-1α expression level is of at most 100 pg/ml, preferably of at most 50, 40, 30, 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 pg/ml; and/or the VEGF expression level is of at least 200 pg/ml in the cell culture medium, preferably of at least 250, 260, 270, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289 or 290 pg/ml; wherein said cell preparation is cultured in hypoxic conditions, preferably at about 0.1% O 2 , and at high concentration of glucose, preferably at about 4.5 g/l of glucose, before measuring the expression level. 
     
     
         23 . The in vitro method according to  claim 15 , wherein said cell preparation is substantially pure when the SDF-1α expression level is of at most 100 pg/ml, preferably of at most 50, 40, 30, 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 pg/ml; and/or the VEGF expression level is of at least 90 pg/ml in the cell culture medium, preferably of at least 95, 100, 105, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119 or 120 pg/ml, wherein said cell preparation is cultured at tissular oxygen tension, preferably at about 5% O 2 , and at high concentration of glucose, preferably at about 4.5 g/l of glucose, before measuring the expression level. 
     
     
         24 . The in vitro method according to  claim 15 , wherein said method is for assessing the quality or purity of a cell preparation comprising mesenchymal stem cells (MSC), wherein said cell preparation comprising MSC is to be used as MSC-based cell therapy product in regenerative medicine. 
     
     
         25 . A cell population identified by an in vitro method for assessing, evaluating and/or monitoring the purity of a cell preparation comprising mesenchymal stem cells (MSC), wherein said method comprises measuring the expression level of at least one growth factor expressed by said cell preparation, wherein said at least one growth factor is SDF-1α and/or VEGF. 
     
     
         26 . A kit for implementing an in vitro method for assessing, evaluating and/or monitoring the purity of a cell preparation comprising mesenchymal stem cells (MSC), wherein said method comprises measuring the expression level of at least one growth factor expressed by said cell preparation, wherein said at least one growth factor is SDF-1α and/or VEGF, wherein said kit comprises means for determining or measuring the expression level of at least one growth factor, optionally further comprising the reference for comparing the expression level of said at least one growth factor.