Human natural killer cells and mature T lymphocytes express identical CD3 zeta subunits as defined by cDNA cloning and sequence analysis

Eur J Immunol. 1990 Aug;20(8):1741-5. doi: 10.1002/eji.1830200818.


In order to characterize the CD3 zeta-related protein found in human natural killer (NK) cells and compare it with CD3 zeta expressed in T lymphocytes, the present study was performed. A polyclonal CD3-CD16+NK population displaying a strong non-major histocompatibility complex-restricted cytotoxic activity against the NK target K-562 was isolated and a product corresponding to CD3 zeta amplified using the polymerase chain reaction method. This 0.6-kb product was present in similar amounts in NK cells and T cells. In contrast, a product corresponding to CD3 delta was amplified from T lymphocytes exclusively. Thus, the CD3 zeta product detected in NK cells did not originate from contaminating T cells. DNA sequence analysis of two independent polymerase chain reaction products from the NK cells demonstrates that human NK cells and mature T cells share a CD3 zeta subunit with an identical primary amino acid sequence. The nucleotide sequence of a third NK-derived cDNA revealed an insertion of a CAG triplet encoding an additional glutamine residue in the cytoplasmic domain. Since this residue is encoded by nucleotides at a putative RNA splice junction, it possibly results from a difference in pre-mRNA splicing. Taken together, these data show that CD3 zeta is not structurally distinct in NK cells and in T lymphocytes.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Antigens, Differentiation, T-Lymphocyte / biosynthesis*
  • Antigens, Differentiation, T-Lymphocyte / genetics
  • Base Sequence
  • CD3 Complex
  • Chromosome Mapping
  • Cloning, Molecular
  • DNA / analysis
  • Gene Expression*
  • Humans
  • In Vitro Techniques
  • Killer Cells, Natural / immunology*
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • Receptors, Antigen, T-Cell / biosynthesis*
  • Receptors, Antigen, T-Cell / genetics
  • Sequence Homology, Nucleic Acid
  • T-Lymphocytes / immunology*
  • Transcription, Genetic


  • Antigens, Differentiation, T-Lymphocyte
  • CD3 Complex
  • Receptors, Antigen, T-Cell
  • DNA