Project description:Chronic viral infections caused by HIV in humans or LCMV in mice are characterized by immunodeficiency and chronic inflammation. During chronification, T cells progressively lose effector functions, a process associated with immunoregulatory pathways and known as T-cell exhaustion. A link between ‘exhaustive’ T-cell reprogramming and chronic inflammation has not been established. Using a systems biology approach we demonstrate in HIV and LCMV infection that TNF, a prototypical mediator of chronic inflammation, functions upstream of major immunoregulatory pathways in T cells during chronic viral infection. In vivo blockade of TNFR-signaling interferes with the exhaustive T-cell program during chronic infection and reduces viral loads by several log. Continuous TNFR-signaling during disease progression towards chronic infection seems to be causative for T-cell exhaustion and an important link between immunodeficiency and chronic inflammation. TNF blockade might represent a novel therapeutic option during late stage infections caused by HIV and other virus causing chronic infections. CD4+ T cells from Infliximab or control treatment of chronic LCMV infected animals
Project description:Chronic viral infections caused by HIV in humans or LCMV in mice are characterized by immunodeficiency and chronic inflammation. During chronification, T cells progressively lose effector functions, a process associated with immunoregulatory pathways and known as T-cell exhaustion. A link between ‘exhaustive’ T-cell reprogramming and chronic inflammation has not been established. Using a systems biology approach we demonstrate in HIV and LCMV infection that TNF, a prototypical mediator of chronic inflammation, functions upstream of major immunoregulatory pathways in T cells during chronic viral infection. In vivo blockade of TNFR-signaling interferes with the exhaustive T-cell program during chronic infection and reduces viral loads by several log. Continuous TNFR-signaling during disease progression towards chronic infection seems to be causative for T-cell exhaustion and an important link between immunodeficiency and chronic inflammation. TNF blockade might represent a novel therapeutic option during late stage infections caused by HIV and other virus causing chronic infections. CD4+ T cells from Infliximab or control treatment of acute LCMV infected animals
Project description:Chronic viral infections caused by HIV in humans or LCMV in mice are characterized by immunodeficiency and chronic inflammation. During chronification, T cells progressively lose effector functions, a process associated with immunoregulatory pathways and known as T-cell exhaustion. A link between ‘exhaustive’ T-cell reprogramming and chronic inflammation has not been established. Using a systems biology approach we demonstrate in HIV and LCMV infection that TNF, a prototypical mediator of chronic inflammation, functions upstream of major immunoregulatory pathways in T cells during chronic viral infection. In vivo blockade of TNFR-signaling interferes with the exhaustive T-cell program during chronic infection and reduces viral loads by several log. Continuous TNFR-signaling during disease progression towards chronic infection seems to be causative for T-cell exhaustion and an important link between immunodeficiency and chronic inflammation. TNF blockade might represent a novel therapeutic option during late stage infections caused by HIV and other virus causing chronic infections. TNF stimulation of CD4+ T cells to generate a CD4+ T-cell specific RNA-fingerprint
Project description:Chronic viral infections caused by HIV in humans or LCMV in mice are characterized by immunodeficiency and chronic inflammation. During chronification, T cells progressively lose effector functions, a process associated with immunoregulatory pathways and known as T-cell exhaustion. A link between ‘exhaustive’ T-cell reprogramming and chronic inflammation has not been established. Using a systems biology approach we demonstrate in HIV and LCMV infection that TNF, a prototypical mediator of chronic inflammation, functions upstream of major immunoregulatory pathways in T cells during chronic viral infection. In vivo blockade of TNFR-signaling interferes with the exhaustive T-cell program during chronic infection and reduces viral loads by several log. Continuous TNFR-signaling during disease progression towards chronic infection seems to be causative for T-cell exhaustion and an important link between immunodeficiency and chronic inflammation. TNF blockade might represent a novel therapeutic option during late stage infections caused by HIV and other virus causing chronic infections.
Project description:Chronic viral infections caused by HIV in humans or LCMV in mice are characterized by immunodeficiency and chronic inflammation. During chronification, T cells progressively lose effector functions, a process associated with immunoregulatory pathways and known as T-cell exhaustion. A link between ‘exhaustive’ T-cell reprogramming and chronic inflammation has not been established. Using a systems biology approach we demonstrate in HIV and LCMV infection that TNF, a prototypical mediator of chronic inflammation, functions upstream of major immunoregulatory pathways in T cells during chronic viral infection. In vivo blockade of TNFR-signaling interferes with the exhaustive T-cell program during chronic infection and reduces viral loads by several log. Continuous TNFR-signaling during disease progression towards chronic infection seems to be causative for T-cell exhaustion and an important link between immunodeficiency and chronic inflammation. TNF blockade might represent a novel therapeutic option during late stage infections caused by HIV and other virus causing chronic infections.
Project description:CD4 and CD8 T cells display functional defects during chronic infection such as loss of certain cytokines. Recent studies have suggested that CD4 T cells may actually gain other functions, however. Here, we analyzed gene expression profiles from LCMV-specific CD4 and CD8 T cells throughout the response to either acute LCMV or chronic LCMV infection. This alllowed us to identify CD4-specific changes during chronic infection compared to acute infection but also revealed shared core regulators between CD4 and CD8 T cells. LCMV-specific CD4 and CD8 T cells were isolated 6, 8, 15 and 30 days post infection with LCMV Armstrong or LCMV clone 13. Naïve CD4 and CD8 T cells were also isolated from naïve mice as comparisons. Four replicates of each sample were hybridized. The only exception is LCMV-specific CD4 T cells isolated 6 days post infection with LCMV-Arm where only three replicates were hybridized.