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Transmitted/founder simian immunodeficiency virus envelope sequences in vesicular stomatitis and Semliki forest virus vector immunized rhesus macaques.

Gambhira R, Keele BF, Schell JB, Hunter MJ, Dufour JP, Montefiori DC, Tang H, Rose JK, Rose N, Marx PA - PLoS ONE (2014)

Bottom Line: We used single genome amplification and phylogenetic analyses to characterize transmitted/founder SIVs both in the inoculum and in immunized-infected rhesus monkeys.We obtained 246 full-length envelope sequences from SIVsmE660 infected macaques at the peak of infection and determined the number of transmitted/founder variants per animal.Because there were only 2 infected animals in the gag-env vaccinated rhesus compared to 10 infected rhesus in the other 2 groups, the significance of finding single env variants in the gag-env vaccinated group could not be established.

View Article: PubMed Central - PubMed

Affiliation: Division of Microbiology, Tulane National Primate Research Center, Tulane University, Covington, Louisiana, United States of America.

ABSTRACT
Identification of transmitted/founder simian immunodeficiency virus (SIV) envelope sequences responsible for infection may prove critical for understanding HIV/SIV mucosal transmission. We used single genome amplification and phylogenetic analyses to characterize transmitted/founder SIVs both in the inoculum and in immunized-infected rhesus monkeys. Single genome amplification of the SIVsmE660 inoculum revealed a maximum diversity of 1.4%. We also noted that the consensus sequence of the challenge stock differed from the vaccine construct in 10 amino acids including 3 changes in the V4 loop. Viral env was prepared from rhesus plasma in 3 groups of 6 immunized with vesicular stomatitis virus (VSV) vectors and boosted with Semliki forest virus (SFV) replicons expressing (a) SIVsmE660 gag-env (b) SIVsmE660 gag-env plus rhesus GM-CSF and (c) control influenza hemagglutinin protein. Macaques were immunized twice with VSV-vectors and once with SFV vector and challenged intrarectally with 4000 TCID50. Single genome amplification characterized the infections of 2 unprotected animals in the gag-env immunized group, both of which had reduced acute plasma viral loads that ended as transient infections indicating partial immune control. Four of 6 rhesus were infected in the gag-env + GM-CSF group which demonstrated that GM-CSF abrogated protection. All 6 animals from the control group were infected having high plasma viral loads. We obtained 246 full-length envelope sequences from SIVsmE660 infected macaques at the peak of infection and determined the number of transmitted/founder variants per animal. Our analysis found that 2 of 2 gag-env vaccinated but infected macaques exhibited single but distinct virus envelope lineages whereas rhesus vaccinated with gag-env-GM-CSF or HA control exhibited both single and multiple env lineages. Because there were only 2 infected animals in the gag-env vaccinated rhesus compared to 10 infected rhesus in the other 2 groups, the significance of finding single env variants in the gag-env vaccinated group could not be established.

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Related in: MedlinePlus

Comparison of E660 viral swarm sequences in the challenge stock to the E660 vaccine construct.The full-length E660 sequences were trimmed to match the vaccine construct sequence. (A) Neighbor-joining phylogenetic tree with all 58 env sequences compared against the vaccine construct. (B) Highlighter plot showing the silent (green) and non-silent (red) changes in all 58 trimmed envelope sequences compared to the E660-vaccine construct.
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pone-0109678-g003: Comparison of E660 viral swarm sequences in the challenge stock to the E660 vaccine construct.The full-length E660 sequences were trimmed to match the vaccine construct sequence. (A) Neighbor-joining phylogenetic tree with all 58 env sequences compared against the vaccine construct. (B) Highlighter plot showing the silent (green) and non-silent (red) changes in all 58 trimmed envelope sequences compared to the E660-vaccine construct.

Mentions: All full-length envelope sequences of SIVe660 inoculum were compared to the E660-envelope used in the vaccine construct (Fig. 3A). The stock viral sequences were trimmed to match the envelope sequence in the vaccine construct which lacked ∼500 bp at the C-terminus for facilitating the packaging of envelope into VSV vectors. The SIVsmE660 env nucleotide sequence used in the vaccine construct differed from the stock sequences on average by 2% and exhibited both silent and non-silent mutations (Fig. 3B). The inoculum consensus envelope sequence was also compared to the vaccine construct to determine the conserved and non-conserved changes between the two. In total, there were ten amino acid changes in the inoculum consensus compared to the vaccine construct. No major changes were noted in the variable loops of gp120 except for three amino acid changes in the V4 loop (G425S, E429 R and K434R) (data not shown). Finally, none of the swarm amino acid sequence was identical to the E660 vaccine construct sequence with the closest match being 11 amino acids apart.


Transmitted/founder simian immunodeficiency virus envelope sequences in vesicular stomatitis and Semliki forest virus vector immunized rhesus macaques.

Gambhira R, Keele BF, Schell JB, Hunter MJ, Dufour JP, Montefiori DC, Tang H, Rose JK, Rose N, Marx PA - PLoS ONE (2014)

Comparison of E660 viral swarm sequences in the challenge stock to the E660 vaccine construct.The full-length E660 sequences were trimmed to match the vaccine construct sequence. (A) Neighbor-joining phylogenetic tree with all 58 env sequences compared against the vaccine construct. (B) Highlighter plot showing the silent (green) and non-silent (red) changes in all 58 trimmed envelope sequences compared to the E660-vaccine construct.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4215841&req=5

pone-0109678-g003: Comparison of E660 viral swarm sequences in the challenge stock to the E660 vaccine construct.The full-length E660 sequences were trimmed to match the vaccine construct sequence. (A) Neighbor-joining phylogenetic tree with all 58 env sequences compared against the vaccine construct. (B) Highlighter plot showing the silent (green) and non-silent (red) changes in all 58 trimmed envelope sequences compared to the E660-vaccine construct.
Mentions: All full-length envelope sequences of SIVe660 inoculum were compared to the E660-envelope used in the vaccine construct (Fig. 3A). The stock viral sequences were trimmed to match the envelope sequence in the vaccine construct which lacked ∼500 bp at the C-terminus for facilitating the packaging of envelope into VSV vectors. The SIVsmE660 env nucleotide sequence used in the vaccine construct differed from the stock sequences on average by 2% and exhibited both silent and non-silent mutations (Fig. 3B). The inoculum consensus envelope sequence was also compared to the vaccine construct to determine the conserved and non-conserved changes between the two. In total, there were ten amino acid changes in the inoculum consensus compared to the vaccine construct. No major changes were noted in the variable loops of gp120 except for three amino acid changes in the V4 loop (G425S, E429 R and K434R) (data not shown). Finally, none of the swarm amino acid sequence was identical to the E660 vaccine construct sequence with the closest match being 11 amino acids apart.

Bottom Line: We used single genome amplification and phylogenetic analyses to characterize transmitted/founder SIVs both in the inoculum and in immunized-infected rhesus monkeys.We obtained 246 full-length envelope sequences from SIVsmE660 infected macaques at the peak of infection and determined the number of transmitted/founder variants per animal.Because there were only 2 infected animals in the gag-env vaccinated rhesus compared to 10 infected rhesus in the other 2 groups, the significance of finding single env variants in the gag-env vaccinated group could not be established.

View Article: PubMed Central - PubMed

Affiliation: Division of Microbiology, Tulane National Primate Research Center, Tulane University, Covington, Louisiana, United States of America.

ABSTRACT
Identification of transmitted/founder simian immunodeficiency virus (SIV) envelope sequences responsible for infection may prove critical for understanding HIV/SIV mucosal transmission. We used single genome amplification and phylogenetic analyses to characterize transmitted/founder SIVs both in the inoculum and in immunized-infected rhesus monkeys. Single genome amplification of the SIVsmE660 inoculum revealed a maximum diversity of 1.4%. We also noted that the consensus sequence of the challenge stock differed from the vaccine construct in 10 amino acids including 3 changes in the V4 loop. Viral env was prepared from rhesus plasma in 3 groups of 6 immunized with vesicular stomatitis virus (VSV) vectors and boosted with Semliki forest virus (SFV) replicons expressing (a) SIVsmE660 gag-env (b) SIVsmE660 gag-env plus rhesus GM-CSF and (c) control influenza hemagglutinin protein. Macaques were immunized twice with VSV-vectors and once with SFV vector and challenged intrarectally with 4000 TCID50. Single genome amplification characterized the infections of 2 unprotected animals in the gag-env immunized group, both of which had reduced acute plasma viral loads that ended as transient infections indicating partial immune control. Four of 6 rhesus were infected in the gag-env + GM-CSF group which demonstrated that GM-CSF abrogated protection. All 6 animals from the control group were infected having high plasma viral loads. We obtained 246 full-length envelope sequences from SIVsmE660 infected macaques at the peak of infection and determined the number of transmitted/founder variants per animal. Our analysis found that 2 of 2 gag-env vaccinated but infected macaques exhibited single but distinct virus envelope lineages whereas rhesus vaccinated with gag-env-GM-CSF or HA control exhibited both single and multiple env lineages. Because there were only 2 infected animals in the gag-env vaccinated rhesus compared to 10 infected rhesus in the other 2 groups, the significance of finding single env variants in the gag-env vaccinated group could not be established.

Show MeSH
Related in: MedlinePlus