Cell processing using magnetic particles
View Patent ↗The present invention relates to compositions comprising magnetic particles, the methods of using these compositions in processing animal sperm, the resulting sperm and embryo products, and the methods of use of these compositions to increase the efficiency, efficacy and/or speed of cell processing and artificial insemination techniques.
1. A method of sex-sorting sperm cells comprising the steps of:
forming a composition comprising the sperm cells and magnetic particles, the sperm cells comprising viable sperm cells and dead or damaged sperm cells and each magnetic particle being no greater than 1000 nm in size and coated with a chargeable silicon-containing compound and comprising a negative zeta potential charge;
binding a portion of the dead or damaged sperm cells to the magnetic particles through an electrical charge interaction;
magnetically separating the bound dead or damaged sperm cells from the unbound viable sperm cells; and
sex-sorting the separated unbound viable sperm cells, by isolating X chromosome-bearing sperm cells or Y chromosome-bearing sperm cells into a separate subpopulation of viable sex-sorted sperm cells, or by photo-damaging sperm cells bearing an undesired sex chromosome.
2. The method of claim 1 , wherein the composition has a pH of 6.5 or higher.
3. The method of claim 1 , wherein the composition has a pH of 7.0 or higher.
4. The method of claim 1 , wherein the composition has a pH of 7.1 or higher.
5. The method of claim 1 , wherein the composition has a pH of 7.2 or higher.
6. The method of claim 1 , wherein the composition has a pH of 7.3 or higher.
7. The method of claim 1 , wherein the composition has a pH of 7.4 or higher.
8. The method of claim 1 , wherein the composition has a pH of 7.5 or higher.
9. The method of claim 1 , wherein the composition has a pH of 8.0 or higher.
10. The method of claim 1 , wherein the composition further comprises a DNA-selective dye.
11. The method of claim 1 , wherein the composition further comprises a buffer.
12. The method of claim 1 , wherein said sperm cells in the composition are porcine sperm cells.
13. The method of claim 1 , wherein said sperm cells in the composition are bovine sperm cells.
14. The method of claim 1 , wherein said sperm cells in the composition are equine sperm cells.
15. The method of claim 1 , wherein said sperm cells in the composition are cervine sperm cells.
16. The method of claim 1 , wherein said sperm cells in the composition are ovine sperm cells.
17. The method of claim 1 , wherein the portion of the dead or damaged sperm cells bound to the magnetic particles is at least about 60% of the dead or damaged sperm.
18. The method of claim 1 , wherein the composition comprises sperm cells at a concentration of 500×10 6 cells/ml or less.
19. The method of claim 1 , wherein the composition comprises sperm cells at a concentration of 400×10 6 cells/ml or less.
20. The method of claim 1 , wherein the composition comprises sperm cells at a concentration of 300×10 6 cells/ml or less.
21. The method of claim 1 , wherein the composition comprises sperm cells at a concentration of 200×10 6 cells/ml or less.
22. The method of claim 1 , wherein the composition comprises sperm cells at a concentration of 180×10 6 cells/ml or less.
23. The method of claim 1 , wherein the composition comprises sperm cells at a concentration of 120×10 6 cells/ml or less.
24. The method of claim 1 , wherein the magnetic particles comprise a carboxyl group.
25. The method of claim 1 , wherein the magnetic particles are non-toxic to said sperm cells.