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What is Cells responsible for GVHD is - and explain in detail?
Graft-versus-host disease (GVHD)

GVHD occurs when immunologically competent cells (T cells) or their precursors are transplanted into immunologically crippled recipients, and the transferred cells recognize alloantigens in the host and attack host tissues.
Most commonly involved tissues in graft versus host disease
Liver
Skin
Gut