Recently, Professor Qin Qiwei's team from the College of Marine Sciences at South China Agricultural University, in collaboration with Dr. Lin Qiang's team from the South China Sea Institute of Oceanology, Chinese Academy of Sciences, has made significant research progress in the origin of T cells in the central nervous system. They have revealed the process and functional characteristics of Slc43a2+ T cells migrating into brain tissues from the spleen of fish infected with viruses. The relevant findings have been published in Science China Life Sciences.
Slc43a2+ T cells migrate from the spleen to the brain to exert antiviral effects. Image provided by the interviewee.
The central nervous system, especially the brain, is considered to have "immune privilege" due to its protection by the blood-brain barrier. Immune cells in the central nervous system act as guardians, with T cells playing a crucial role in resisting foreign viral infections. However, the origin of T cells in the central nervous system of vertebrates remains unclear. While T cells in the peripheral organs of bony fish mainly originate from the thymus, little is known about the source of T cells in the brains of fish.
It has been reported that the team led by Qin Qiwei has long been engaged in research on the pathogenesis of nervous necrosis virus in fish, host antiviral mechanisms, and control techniques. They have established a brain cell atlas in grouper fish, identified target cells of viral infection in the central nervous system, and discovered various immune cells, including T cells, in fish brain tissues.
Further analysis by the study identified nine T cell subgroups in grouper fish. It was found that after viral infection of grouper fish brain tissues, the Slc43a2+ T cell subgroup in both the spleen and brain significantly expanded. Using a spleen-deficient zebrafish model and infection experiments, it was observed that spleen deficiency led to a lack of Slc43a2+ T cells in the brain, suggesting that Slc43a2+ T cells in the brain originate from spleen tissue. Functional analysis of Slc43a2+ T cells revealed that they undergo differentiation and maturation within the spleen before migrating into the brain to exert immune effects.
This study reveals a new pathway for Slc43a2+ T cells to migrate from the spleen to the brain and generate immune responses during viral infection. It provides insights into the origin and function of immune cells in the central nervous system of fish, enriching the theoretical research on antiviral immunity in vertebrates. Moreover, it offers new perspectives for the prevention and treatment of RGNNV through the development of Slc43a2+ T cell functions.
This research was supported by the National Key R&D Program, the National Natural Science Foundation of China, the Natural Science Foundation of Guangdong Province, and other projects.
Related paper: https://doi.org/10.1007/s11427-023-2473-x
