CXCL17, an orphan chemokine, acts as a novel angiogenic and anti-inflammatory factor

Area of Science:

• Immunology
• Molecular Biology
• Gastroenterology

Background:

• Chemokines are crucial for immune cell trafficking in physiological and pathological states.
• CXCL17, an orphan chemokine, has preliminary links to tumor angiogenesis, but its function is unclear.
• Understanding CXCL17's endogenous role is vital for comprehending immune responses in tissues.

Purpose of the Study:

• To elucidate the protein nature and endogenous bioactivity of CXCL17 in the gastric mucosa.
• To investigate CXCL17's chemoattractant properties and signaling pathways.
• To explore CXCL17's effects on immune cell function and inflammatory responses.

Main Methods:

• Real-time PCR and Western blotting were used to assess CXCL17 expression.
• Immunohistochemical staining identified CXCL17 localization in rat gastric mucosa.
• Monocyte/macrophage assays examined chemoattraction, signaling pathways (ERK1/2, p38, JNK), and cytokine production.

Main Results:

• CXCL17 is constitutively and inducibly expressed in rat gastric mucosa, undergoing endoproteolysis.
• Mature CXCL17 chemoattracts monocytes and macrophages via ERK1/2 and p38 signaling.
• CXCL17 induces proangiogenic factors and exhibits anti-inflammatory effects on activated macrophages.

Conclusions:

• CXCL17 plays a significant role in immune cell recruitment within the gastric lamina propria.
• CXCL17 possesses chemoattractant, proangiogenic, and anti-inflammatory functions.
• CXCL17 contributes to tissue repair and anti-inflammation, supporting gastric mucosal integrity.