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Biology subjects

Sanchez, D. J.

Publications and source records attributed to Sanchez, D. J..

2 recordsLinked to original sources

Lentivirus Transduced T Cell Lines Response to Pro-inflammatory and Antiviral Cytokines in the Presence of HIV

Various studies have attempted to understand HIV infection under a diverse range of stimulants including cytokine stimulation. Pro-inflammatory cytokines, such as TNF-, have been shown to reactivate HIV latency by inducing NF-{kappa}B mediated activation of the HIV LTR (long terminal repeats) that contain {kappa}B transcriptional binding sites. Interferon-alpha (IFN-), an anti-viral cytokine, is not well studied as an inducer of HIV activation. However, previous work from our group has shown that HIV can block IFN- signaling in CD4+ T cells presumably to allow for further viral replication. Initially using HEK 293T cells, we moved to CD4+ T cells lines to develop a system to determine how stimulation with different cytokines impacts signaling within T cell lines. We confirmed that in our system TNF- triggers activation of NF-{kappa}B driven reporters but not in the presence of HIV. In addition, we show that the presence of HIV blocks IFN- signaling. Taken together, our system demonstrates that HIV by TNF-, will continue to block IFN- signaling preventing it from impacting HIV activation. This system can now be used to screen for cytokine based and other molecule activators that may be influenced by the presence of HIV.

immunology↗

A Viral-Encoded Homologue of IPS-1 Modulates Innate Immune Signaling During KSHV Lytic Replication

Modulation of innate immunity is critical for virus persistence in a host. In particular, viral-encoded disruption of type I interferon, a major antiviral cytokine induced to fight viral infection, is a key component in the repertoire of viral pathogenicity genes. We have identified a previously undescribed open reading frame within the Kaposis sarcoma-associated herpesvirus (KSHV) genome that encodes a homologue of the human IPS-1 (also referred to as MAVS) protein that we have termed viral-IPS-1 (v-IPS-1). This protein is expressed during the lytic replication program of KSHV, and expression of v-IPS-1 blocks induction of type I interferon upstream of the TRAF3 signaling node including signaling initiated via both the RLR and TLR3/4 signaling axes. This disruption of signaling coincides with destabilization of the cellular innate signaling adaptors IPS-1 and TRIF along with a concatenate stabilization of the TRAF3 protein. Additionally, expression of v-IPS-1 leads to decreased antiviral responses indicating a blot to type I interferon induction during viral infection. Taken together, v-IPS-1 is the first described viral homologue of IPS-1 and this viral protein leads to reprogramming of innate immunity through modulation of type I interferon signaling during KSHV lytic replication.

microbiology↗