Identification in gelada baboons (Theropithecus gelada) of a distinct simian T-cell lymphotropic virus type 3 with a broad range of Western blot reactivity

J Gen Virol. 2004 Feb;85(Pt 2):507-519. doi: 10.1099/vir.0.19630-0.

Abstract

Antibodies to simian T-cell lymphotropic virus (STLV) were found in serum or plasma from 12 of 23 (52.2 %) gelada baboons (Theropithecus gelada) captive in US zoos. A variety of Western blot (WB) profiles was seen in the 12 seroreactive samples, including human T-cell lymphotropic virus (HTLV)-1-like (n=5, 41.7 %), HTLV-2-like (n=1, 8.3 %), HTLV-untypable (n=4, 33.3 %) and indeterminate (n=2, 16.6 %) profiles. Phylogenetic analysis of tax or env sequences that had been PCR amplified from peripheral blood lymphocyte DNA available from nine seropositive geladas showed that four were infected with identical STLV-1s; these sequences clustered with STLV-1 from Celebes macaques and probably represent recent cross-species infections. The tax sequences from the five remaining geladas were also identical and clustered with STLV-3. Analysis of the complete STLV-3 genome (8917 bp) from one gelada, TGE-2117, revealed that it is unique, sharing only 62 % similarity with HTLV-1/ATK and HTLV-2/Mo. STLV-3/TGE-2117 was closest genetically to STLV-3 from an Eritrean baboon (STLV-3/PH969, 95.6 %) but more distant from STLV-3s from red-capped mangabeys from Cameroon and Nigeria (STLV-3/CTO-604, 87.7 %, and STLV-3/CTO-NG409, 87.2 %, respectively) and Senegalese baboons (STLV-3/PPA-F3, 88.4 %). The genetic relatedness of STLV-3/TGE-2117 to STLV-3 was confirmed by phylogenetic analysis of a concatenated gag-pol-env-tax sequence (6795 bp). An ancient origin of 73 628-109 809 years ago for STLV-3 was estimated by molecular clock analysis of third-codon positions of gag-pol-env-tax sequences. LTR sequences from five STLV-3-positive geladas were >99 % identical and clustered with that from a Papio anubisxP. hamadryas hybrid Ethiopian baboon, suggesting a common source of STLV-3 in these sympatric animals. LTR sequences obtained 20 years apart from a mother-infant pair were identical, providing evidence of both mother-to-offspring transmission and a high genetic stability of STLV-3. Since STLV-3-infected primates show a range of HTLV-like WB profiles and have an ancient origin, further studies using STLV-3-specific testing are required to determine whether STLV-3 infects humans, especially in regions of Africa where STLV-3 is endemic.

MeSH terms

  • Animals
  • Animals, Zoo / virology*
  • Blotting, Western
  • Carrier State / blood
  • Carrier State / transmission
  • Carrier State / virology*
  • Deltaretrovirus Infections / blood
  • Deltaretrovirus Infections / transmission
  • Evolution, Molecular
  • Female
  • Gene Products, env / analysis
  • Gene Products, tax / analysis
  • Human T-lymphotropic virus 1 / chemistry
  • Human T-lymphotropic virus 1 / genetics
  • Human T-lymphotropic virus 1 / immunology
  • Human T-lymphotropic virus 2 / chemistry
  • Human T-lymphotropic virus 2 / genetics
  • Human T-lymphotropic virus 2 / immunology
  • Likelihood Functions
  • Male
  • Molecular Sequence Data
  • Phylogeny
  • Primate T-lymphotropic virus 3 / genetics
  • Primate T-lymphotropic virus 3 / immunology
  • Primate T-lymphotropic virus 3 / isolation & purification*
  • Sequence Homology, Nucleic Acid
  • Theropithecus / virology*
  • United States

Substances

  • Gene Products, env
  • Gene Products, tax

Associated data

  • GENBANK/AY217650
  • GENBANK/AY241678
  • GENBANK/AY241679
  • GENBANK/AY241680
  • GENBANK/AY241681
  • GENBANK/AY241682
  • GENBANK/AY241683
  • GENBANK/AY241684
  • GENBANK/AY241685
  • GENBANK/AY241686
  • GENBANK/AY241687
  • GENBANK/AY241688
  • GENBANK/AY241689
  • GENBANK/AY241690
  • GENBANK/AY241691
  • GENBANK/AY241692
  • GENBANK/AY241693