Limits...
Characterization of two distinct early post-entry blocks to HIV-1 in common marmoset lymphocytes

View Article: PubMed Central - PubMed

ABSTRACT

In nature, primate lentiviruses infect humans and several Old World monkeys and apes. However, to date, lentiviruses infecting New World monkeys have not been described. We studied the susceptibility of common marmoset cells to HIV-1 infection and observed the presence of post-entry blocks to the early phase of HIV-1 infection in peripheral blood lymphocytes (PBLs) and a B lymphocytic cell line (B-LCL). The blocks present in these cells are dominant and phenotypically different from each other. In PBLs, the block occurs at the level of reverse transcription, reducing the accumulation of early and late transcripts, similar to the block imposed by TRIM5α. However, we have found that marmoset TRIM5α does not block HIV-1. In contrast, the restriction factor present in B-LCLs blocks HIV-1 replication at a later step, after nuclear entry, and inhibits integration. Additionally, we have identified an HIV-1 capsid mutant, N74D, that is able to escape the restriction in the marmoset B-LCLs. Our results suggest that the factors responsible for the blocks present in marmoset PBLs and B-LCLs are different. We propose the existence of at least two new restriction factors able to block HIV-1 infection in marmoset lymphocytes.

No MeSH data available.


Related in: MedlinePlus

Characterization of the post-entry block to HIV-1 in B-LCLs.Human (hu) or marmoset (mar) B-LCLs were challenged with single-cycle HIV-1 WT or N74D capsid mutant luciferase reporter viruses pseudotyped with VSV-G. (A) Cells were pre-treated with 500 U/ml of universal IFN-α for 24 hours before the infection. (B) Cells were pre-treated with 4 μM As2O3 for 3 hours before the infection. The cells were maintained in the presence of the treatment for 24 hours after the viral challenge. Forty-eight hours post-challenge, the infectivity of the viruses was determined by measuring the relative luciferase activity (RLU) in the cells. The results of five independent experiments are shown. Reported p-values (2-tailed) were obtained with a paired t-test (untreated versus treated cells). NT, no treatment.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5120322&req=5

f8: Characterization of the post-entry block to HIV-1 in B-LCLs.Human (hu) or marmoset (mar) B-LCLs were challenged with single-cycle HIV-1 WT or N74D capsid mutant luciferase reporter viruses pseudotyped with VSV-G. (A) Cells were pre-treated with 500 U/ml of universal IFN-α for 24 hours before the infection. (B) Cells were pre-treated with 4 μM As2O3 for 3 hours before the infection. The cells were maintained in the presence of the treatment for 24 hours after the viral challenge. Forty-eight hours post-challenge, the infectivity of the viruses was determined by measuring the relative luciferase activity (RLU) in the cells. The results of five independent experiments are shown. Reported p-values (2-tailed) were obtained with a paired t-test (untreated versus treated cells). NT, no treatment.

Mentions: To assess if interferon-α (IFN-α) plays a role in the post-entry block to HIV-1 in marmoset B-LCLs, we pretreated the cells with 500 U/ml of universal IFN-α for 24 h and then challenged them with VSV-G-pseudotyped HIV-1 luciferase reporter viruses. Treatment of human and marmoset B-LCLs with IFN-α significantly decreased the infectivity of WT HIV-1 (Fig. 8A). IFN-α treatment also decreased the infectivity of the escape mutant N74D (Fig. 8A). Apparently, IFN-α treatment results in a general decrease in HIV-1 infectivity in these B-LCLs. However, the decrease of infectivity observed in the marmoset B-LCLs for the N74D mutant was statistically less significant (p = 0.068), suggesting that in the marmoset cells this mutant was affected to a lesser degree by IFN-α treatment.


Characterization of two distinct early post-entry blocks to HIV-1 in common marmoset lymphocytes
Characterization of the post-entry block to HIV-1 in B-LCLs.Human (hu) or marmoset (mar) B-LCLs were challenged with single-cycle HIV-1 WT or N74D capsid mutant luciferase reporter viruses pseudotyped with VSV-G. (A) Cells were pre-treated with 500 U/ml of universal IFN-α for 24 hours before the infection. (B) Cells were pre-treated with 4 μM As2O3 for 3 hours before the infection. The cells were maintained in the presence of the treatment for 24 hours after the viral challenge. Forty-eight hours post-challenge, the infectivity of the viruses was determined by measuring the relative luciferase activity (RLU) in the cells. The results of five independent experiments are shown. Reported p-values (2-tailed) were obtained with a paired t-test (untreated versus treated cells). NT, no treatment.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5120322&req=5

f8: Characterization of the post-entry block to HIV-1 in B-LCLs.Human (hu) or marmoset (mar) B-LCLs were challenged with single-cycle HIV-1 WT or N74D capsid mutant luciferase reporter viruses pseudotyped with VSV-G. (A) Cells were pre-treated with 500 U/ml of universal IFN-α for 24 hours before the infection. (B) Cells were pre-treated with 4 μM As2O3 for 3 hours before the infection. The cells were maintained in the presence of the treatment for 24 hours after the viral challenge. Forty-eight hours post-challenge, the infectivity of the viruses was determined by measuring the relative luciferase activity (RLU) in the cells. The results of five independent experiments are shown. Reported p-values (2-tailed) were obtained with a paired t-test (untreated versus treated cells). NT, no treatment.
Mentions: To assess if interferon-α (IFN-α) plays a role in the post-entry block to HIV-1 in marmoset B-LCLs, we pretreated the cells with 500 U/ml of universal IFN-α for 24 h and then challenged them with VSV-G-pseudotyped HIV-1 luciferase reporter viruses. Treatment of human and marmoset B-LCLs with IFN-α significantly decreased the infectivity of WT HIV-1 (Fig. 8A). IFN-α treatment also decreased the infectivity of the escape mutant N74D (Fig. 8A). Apparently, IFN-α treatment results in a general decrease in HIV-1 infectivity in these B-LCLs. However, the decrease of infectivity observed in the marmoset B-LCLs for the N74D mutant was statistically less significant (p = 0.068), suggesting that in the marmoset cells this mutant was affected to a lesser degree by IFN-α treatment.

View Article: PubMed Central - PubMed

ABSTRACT

In nature, primate lentiviruses infect humans and several Old World monkeys and apes. However, to date, lentiviruses infecting New World monkeys have not been described. We studied the susceptibility of common marmoset cells to HIV-1 infection and observed the presence of post-entry blocks to the early phase of HIV-1 infection in peripheral blood lymphocytes (PBLs) and a B lymphocytic cell line (B-LCL). The blocks present in these cells are dominant and phenotypically different from each other. In PBLs, the block occurs at the level of reverse transcription, reducing the accumulation of early and late transcripts, similar to the block imposed by TRIM5α. However, we have found that marmoset TRIM5α does not block HIV-1. In contrast, the restriction factor present in B-LCLs blocks HIV-1 replication at a later step, after nuclear entry, and inhibits integration. Additionally, we have identified an HIV-1 capsid mutant, N74D, that is able to escape the restriction in the marmoset B-LCLs. Our results suggest that the factors responsible for the blocks present in marmoset PBLs and B-LCLs are different. We propose the existence of at least two new restriction factors able to block HIV-1 infection in marmoset lymphocytes.

No MeSH data available.


Related in: MedlinePlus