Culturing human cells and tissues in an N-glycolylneuraminic acid-free environment
This application is in the field of sialic acid chemistry, metabolism, antigenicity, and the production of transgenic non-human mammals with altered sialic acid production. More particularly, this application relates to N-glycolylneuraminic acid (Neu5Gc) being an immunogen in humans, and the production of Neu5Gc-free mammalian products for laboratory and human use.
1 . A method for preparing a culture of human cells devoid of N-glycolylneuraminic acid (Neu5Gc) comprising the steps of:
preselecting the human cells to be cultured;
placing the human cells in a culture medium comprising serum selected from the group consisting of: animal-free serum replacement, mammalian-free serum, human serum, heat-inactivated human serum, and Neu5Gc deficient animal serum; and
allowing the human cells to grow in the culture medium to a desired density.
2 . The method of claim 1 , wherein the human cells are selected from the group consisting of human embryonic stem cells, embryoid bodies, carcinoma cells and differentiated progenitor cells.
3 . The method of claim 1 , wherein the cultured cells after growing to a desired density comprise less than 1% Neu5Gc by weight when compared to total sialic acids.
4 . The method of claim 1 , wherein the culture medium comprises animal free serum replacement.
5 . The method of claim 1 , wherein the culture medium comprises human serum.
6 . The method of claim 1 , wherein the cells are not grown on a non-human feeder layer.
7 . The method of claim 1 , wherein the cells are human embryonic stem cells, and wherein the medium comprises human serum as the only serum source, and wherein the human embryonic stem cells are cultured on a human cell feeder layer, and wherein the human embryonic stem cells have never before been exposed to animal products.
8 . The method of claim 1 , wherein the cells are embryoid bodies, and wherein the medium comprises human serum as the only serum source.
9 . The method of claim 1 , wherein the cells and the medium after the cells have grown to the desired density contain low levels of anti-Neu5Gc antibodies.