Expression of CD3ϵ, CD3ζ, and RAG-1/RAG-2 in Decidual CD56+NK Cells

In early pregnancy the uterine mucosa, the decidua, is infiltrated by numerous CD56bright, CD16−natural killer (NK) cells. In this paper we have shown that unlike adult peripheral blood NK cells these uterine NK cells express cytoplasmic CD3 and CD3ζ, but CD3γ and CD3δ were not found in the majority of cells. In contrast to previous reports, there was no evidence of RAG-1 nor RAG-2 expression in decidual NK cells. These findings have implications for the ontogeny and development of decidual NK cells.