Human T Lymphocytes Are Permissive for Dengue Virus Replication

Area of Science:

• Virology
• Immunology
• Cell Biology

Background:

• Dengue virus (DV) infection causes a spectrum of illness, from mild febrile disease to life-threatening hemorrhage.
• While DV infects various immune cells, the interaction between DV and T lymphocytes remains poorly understood.
• T lymphocytes play crucial roles in adaptive immunity, including regulating B cell antibody production and mediating cytotoxic responses.

Purpose of the Study:

• To investigate the susceptibility of primary human naive T cells to DV infection.
• To characterize the functional consequences of DV infection on T lymphocytes.
• To determine the presence and role of DV-infected T cells in dengue patients.

Main Methods:

• In vitro infection of primary human CD4+ and CD8+ T cells and monocytes with DV.
• Assessment of viral replication, virus particle release, and T cell activation markers.
• Analysis of T cell apoptosis using annexin V and polycaspase assays.
• Detection of DV RNA and proteins in T cells from acutely infected dengue patients.

Main Results:

• Primary human naive CD4+ and CD8+ T cells are permissive to DV infection, supporting viral replication and release of infectious virions.
• DV infection activates both CD4+ and CD8+ T cells, although preactivation reduces susceptibility.
• T lymphocytes exhibit resistance to DV-induced apoptosis, unlike monocytes.
• DV RNA and proteins are detected in both CD4+ and CD8+ T cells from dengue patients.

Conclusions:

• T lymphocytes are a novel target for DV infection, supporting viral replication both in vitro and in vivo.
• DV-infected T cells may serve as a viral reservoir during the acute phase of dengue infection.
• These findings have implications for understanding dengue pathogenesis and developing effective vaccines and therapies.