Neuron: Heavy!

The nervous system and the peripheral immune system are closely connected to each other through neurotransmitters and cytokines for a two-way dialogue: peripheral immune cells can infiltrate the brain parenchyma to play an immune response under pathological conditions; while the nervous system can also regulate immune responses in an autoimmune state

Peripheral immune cells can infiltrate into the brain parenchyma to play an immune response under pathological conditions; while the nervous system can also regulate immune responses under autoimmune conditions

The spleen is the largest immune organ

On February 7, 2022, the research team of Cao Gang from the School of Biomedicine and Health of Huazhong Agricultural University revealed in the journal Neuron that neuropeptide Y (NPY) precisely regulates the inflammatory response of the spleen, acting as an "interactive language" between the immune system and the central nervous system .

Cao Gang of Huazhong Agricultural University revealed that neuropeptide Y (NPY) precisely regulates the inflammatory response of the spleen and acts as an "interactive language" between the immune system and the central nervous system.

Figure 1: Virus tracing experiments reveal nerve fiber input to the spleen

Figure 1: Virus tracing experiments reveal nerve fiber input to the spleen Figure 1: Virus tracing experiments reveal nerve fiber input to the spleen

The researchers found that there were neural projections in the adrenal ganglia (SrG) and celiac ganglia (CG) after retrograde tracer virus injection in the spleen of rats, and about 60% of the projection neurons were NPY neurons (Figure 1)

Figure 2: Changes in spleen immune cells caused by virus silencing of NPY

Figure 2: Changes in spleen immune cells after virus silencing NPY Figure 2: Changes in spleen immune cells after virus silencing NPY

To further explore how NPY in the SrG-CG region senses the immune response, the researchers specifically reduced the expression of NPY in the SrG-CG region of rats by virus interference technology, and the number of spleen immune T cells was significantly reduced and the number of B cells was increased

Gene sequencing results showed that NPY receptor NPY1R was hardly expressed in B cells, less expressed in T cells, and more expressed in macrophages

The expression of IL-6, TNF-α, IL-1β and other inflammatory factors were up-regulated by lipopolysaccharide, and the expression of these inflammatory factors was further increased after knockdown of NPY in SrG-CG neurons of rats, which could be abolished after removal of spleen nerve branches.

Figure 3: Drosophila infection with bacteria experiment

Figure 3: Drosophila infection with bacteria Figure 3: Drosophila infection with bacteria

In addition, reducing the expression of NPY can reduce the survival rate of rats infected with E.

Serum NPY levels are significantly reduced in patients with autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus

Patients with autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus patients with autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus

Collectively, we found here that immune responses can activate NPY neurons in the SrG-CG region to specifically regulate immune cells in the spleen through splenic nerve branches to play an immunoregulatory role

In this paper, it was found that the immune response can activate NPY neurons in the SrG-CG region to specifically regulate immune cells in the spleen to play an immunoregulatory role through splenic nerve branches.

Original source:

Jinsong Yu, et al.

Neuron-derived neuropeptide Y fine-tunes the splenic immune responses