The manufacturing process of cloned embryonic primary cells is very similar to the process of cloning dogs or cats. If a cloned embryo in a surrogate mother’s uterus is left there without being retrieved, a cloned animal will be born. This way, the DNA of primary cells and pets is 100% identical, because the cloned embryonic primary cells are manufactured through animal cloning protocols. Therefore, the immune rejection problem, one of the biggest obstacles to cell therapy, can be solved fundamentally.
Additionally, cloned embryonic primary cells are simply physically dissociated cells from a cloned embryo and the manufacturing process does not involve artificial modifications. This has a very important meaning in predicting the in vivo safety of cells as a treatment. On the other hand, stem cells undergo several artificial modifications during the process of cell therapy manufacturing. For example, in the case of induced pluripotent stem cells, processing steps to reprogram somatic cells to stem cells involve using viruses, plasmid vectors, mRNA, or proteins, and those steps induce the overexpression of somatic cells’ four transcription factors (Oct4, Sox2, Klf4, C-Myc). Likewise, the process to transform embryonic stem cells into cell therapy involves several modifications such as differentiation and proliferation. However, artificially manufactured cells have latent risk factors such as genetic toxicity or chromosome mutations, so in vivo transplantation of artificially manufactured cells often causes side effects like tumors. For the aforementioned reasons, there is no existing FDA-approved stem cell therapy yet in the world. Conversely, cloned embryonic primary cells are simply physically dissociated and purified cells from a cloned embryo that has completed differentiating into all tissues and organs by itself. Manufacturing these cells does not involve any artificial modifications. It is so-called ‘Cell therapy manufactured by nature.’
Most importantly, the greatest advantage of cloned embryonic primary cells is their youth. An embryo is the earliest stage of life, and the tissues separated during this stage are full of young cells, which have healthy vitality and immense ability to divide. Aging pets will naturally restore their youth when these cells are transplanted into the pets.
Then, specifically which cells need to be transplanted to regain youth? Here is a detailed explanation.
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