github link
Accession IconGSE32626

HIV-1 TAT SUPPRESSES THE TCR/CD3 MACHINERY IN HUMAN CD4+ T CELLS

Organism Icon Homo sapiens
Sample Icon 9 Downloadable Samples
Technology Badge Icon Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)

Submitter Supplied Information

Description
Our previous work demonstrated that HIV-1 infection progressively reduces TCR/CD3 expression due to a defect in CD3g gene transcripts. We further found that knocking down expression of the viral tat and/or nef genes was correlated with CD3g transcript and TCR/CD3 surface receptor levels on HIV-1 infected cells. This study was undertaken to investigate the direct effect of HIV-1 Tat expression on the TCR/CD3 machinery. Progressive downregulation from TCR/CD3hi to TCR/CD3lo to TCR/CD3? was observed on Tat expressing cells in a manner that emulated HIV-1 infection, with a lack of CD3g transcripts again responsible for the defect. When Tat cell cultures containing a mixture of TCR/CD3 surface densities were separated into TCR/CD3hi and TCR/CD3lo/? populations, they quickly reverted to a mixed CD3 phenotype. Thus, the progression TCR/CD3hi to TCR/CD3lo to TCR/CD3? is an active, reversible process with receptor levels fluctuating in response to intracellular dynamics. Examination of tat mutants found that the regions involved in Tat-mediated transactivation and TAR binding are required for TCR/CD3 downregulation while the lysine at position 28 and Tat exon 2 are dispensable. Global gene expression, assessed in association with TCR/CD3 downregulation in HIV-1 infected and Tat expressing cells, detected broad suppression of TCR/CD3 signaling, co-stimulation and negative regulatory genes along with target transcription factors, ligands and receptors. A significant subset of the genes altered in HIV-1 infected cells was specifically targeted by Tat in association with TCR/CD3 loss. Our finding that Tat negatively regulates many facets of the TCR/CD3 machinery has important implications for disease pathogenesis.
PubMed ID
No associated PubMed ID
Publication Title
No associated publication
Total Samples
10
Submitter’s Institution
Authors
No associated authors

Samples

Show of 0 Total Samples
Filter
Add/Remove
Accession Code
Title
Specimen part
Cell line
Processing Information
Additional Metadata
No rows found
Loading...