[Characterizing the CD3 epsilon chain from the New World primate Aotus nancymaae].
BACKGROUND
The T-cell receptor (TCR)-associated complex, CD3 (d, g, e) and z-chains are essential transmembrane proteins for signal transduction during T cell activation and immune response, as well as during thymocyte development.


OBJECTIVE
This work established the CD3epsilon-chain primary structure for the New World owl monkey Aotus nancymaae.


METHODS
Total RNA was isolated from peripheral blood mononuclear cells; CD3epsilon molecule was amplified, cloned and sequenced.


RESULTS
The CD3epsilon amino acid sequence was deduced for the owl monkey Aotus nancymaae.> It has an identity for nucleotide and amino acid sequences with the human counterpart of 84% and 76%, respectively. As described in other species, the Aotus CD3-e molecule is very variable in the extracellular region and greatly conserved in the intracellular domain. Even though high variability occurs in the CD3epsilon-extracellular domain, the subregions involved in ectodomain folding are conserved.


CONCLUSIONS
The primary structure suggested that the Aotus protein has a functional role similar to that of humans, and that the initial T-cell activation steps are also similar. However, the great variation observed in CD3epsilon-extracellular region in humans in contrast to the Aotus (especially in areas that are surface-exposed) indicated that some monoclonal antibodies against the human CD3 complex will not recognize these Aotus determinants.
Del Castillo
Hernando
H
Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C, Colombia.
Vernot
Jean Paul
JP
D000595:Amino Acid Sequence; D000818:Animals; D016645:Aotidae / Q000276:immunology*; D001483:Base Sequence; D017252:CD3 Complex / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics / Q000276:immunology*; D017260:Receptor-CD3 Complex, Antigen, T-Cell / Q000235:genetics / Q000276:immunology; D016415:Sequence Alignment; D015398:Signal Transduction / Q000502:physiology
D017252:CD3 Complex; D020033:Protein Isoforms; D017260:Receptor-CD3 Complex, Antigen, T-Cell