Antigen-specific CD4 T-cell help rescues exhausted CD8 T cells during chronic viral infection

Rejuvenating Exhausted T Cells during Chronic Viral Infection

In a recent paper in Nature, show that the immunoreceptor PD-1 is upregulated by "exhausted" T cells during the chronic phase of viral infection in mice. Remarkably, blocking the interaction between PD-1 and its ligand, PD-L1, reactivates these T cells and reduces viral load.

Viral antigen and extensive division maintain virus-specific CD8 T cells during chronic infection

Efficient maintenance of memory CD8 T cells is central to long-term protective immunity. IL-7- and IL-15-driven homeostatic proliferation is essential for long-term memory CD8 T cell persistence after acute infections. During chronic infections, however, virus-specific CD8 T cells respond poorly to these cytokines. Yet, virus-specific CD8 T cells often persist for long periods of time during ch...

Responses Are Larger Than We Think during a Viral Infection: CD4 T Cell Quantifying Antigen-Specific CD4 T Cells

CD4+ T Cells are Exhausted and Show Functional Defects in Chronic Lymphocytic Leukemia

Background: Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the western world. This health problem is caused due to the accumulation of mature B-lymphocytes in the peripheral blood and bone marrow. In the course of cancer, CD4+ T cells become “exhausted” and characterized with poor effector functions and the expression of multiple inhibitory receptors. Objective: To inve...

Cutting edge: cognate CD4 help promotes recruitment of antigen-specific CD8 T cells around dendritic cells.

The cellular orchestration underlying help provided by CD4 T lymphocytes to CD8 T cell responses is not fully understood. We documented that the formation of three-cell clusters occurred as soon as day 1 and relied on long-lasting CD4 and CD8 T cell interactions with dendritic cells (DCs). The influence of CD4 help on CD8 T cell differentiation could be observed as early as the second round of ...