ISSN:
1432-1211
Keywords:
Key words Aotus nancymaae
;
T-cell receptor β-chain
;
TCRBV and TCRBJ genes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract The New World primate Aotus nancymaae is susceptible to infection with the human malaria parasite Plasmodium falciparum and has therefore been recommended by the World Health Organization as a model for the evaluation of malaria vaccine candidates. Recently, we have shown that Aotus TCRVA genes and TCRJA segments exhibit a high degree of similarity to human counterparts. In the present report we used reverse transcription polymerase chain reaction to analyze the sequences of A. nancymaae TCRβ-chain gene rearrangements. Alignment with human sequences and phylogenetic comparison identified 18 distinct Aotus TCRBV genes homologous to the human TCRBV gene families 2, 4, 5, 6, 7, 9, 12, 15, 24, and 28. Multiple Aotus genes were found in the TCRBV4, 5, 6, and 7 families. Some of these TCRBV genes aligned best to the same human gene and thus do not seem to have separate human homologues. Amino acid sequences of the Aotus TCRBV genes were 77 to 90% identical to their closest human counterparts. Ten distinct Aotus TCRBJ segments homologous to the human segments J1-1, J1-2, J1-4, J1-5, J1-6, J2-1, J2-2, J2-3, J2-4, J2-5 were found. In some cases the amino acid sequences of Aotus and human TCRBJ segments were completely identical. A comparison of the proportion of synonymous and non-synonymous substitutions in Aotus vs human β-chain-encoding genes revealed a dominance of synonymous substitutions in TCRBJ segments and of nonsynonymous substitutions in TCRBV segments. Dominance of nonsynonymous substitutions was more pronounced in TCRBV CDR1 and CDR2 regions than in the framework regions. No evidence for the emergence of new TCRBJ segments or TCRBV families was found. These results confirm that the TCR repertoire in primates is remarkably stable and support the concept of using Aotus monkeys as an infection model for the evaluation of future subunit vaccine candidates.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002510050553
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