Expression of CD8αα on T cells engineered to express a tumor-reactive γδTCR was a prerequisite for recognition of all tested tumor cell lines, but coexpression of signaling-deficient CD8α variants or mutants with single residue substitutions in the extracellular domain of CD8α alongside the γδTCR differentially impacted T cell reactivity toward the different tumor targets. Here, CD8A is linked to neoplasm.