Given what we know, we can confirm that if a client that underwent a liver transplant is suffering the rejection of the liver, the culprit is the client's immune system, specifically the T cells.
Therefore, given that T cells are a type of lymphocyte that are in charge of adaptive immune defense and are the cells that will react to the presence of a foreign body, these are the most likely reason for the client's rejection of the newly transplanted liver.
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