FAM19A4 is a novel cytokine ligand of formyl peptide receptor I （FPR 1） and is able to promote the migration and phagocytosis of macrophages

• Published in: 中国免疫学杂志：英文版 no. 5; pp. 615 - 624
• Main Author: Wenyan Wang Ting Li Xiaolin Wang Wanxiong Yuan Yingying Cheng Heyu Zhang Enquan Xu Yingmei Zhang Shuang Shi Dalong Ma Wenling Han
• Format: Journal Article
• Language: English
• Published: 2015
• Subjects: FPR; 受体; 吞噬作用; 巨噬细胞; 细胞因子; 肽; 迁移过程; 配体
• ISSN: 1672-7681; 2042-0226

FAM 19A4 is an abbreviation for family with sequence similarity 19 （chemokine （C-C motif）-Iike） member A4, which is a secretory protein expressed in low levels in normal tissues. The biological functions of FAM19A4 remain to be determined, and its potential receptor（s） is unclarified. In this study, we demonstrated that FAM 19A4 was a classical secretory protein and we verified for the first time that its mature protein is composed of 95 amino acids. We found that the expression of this novel cytokine was upregulated in lipopolysaccharide （LPS）-stimulated monocytes and macrophages and was typically in polarized M 1. FAM 19A4 shows chemotactic activities on macrophages and enhances the macrophage phagocytosis of zymosan both in vitro and in vivo with noticeable increases of the phosphorylation of protein kinase B （Akt）. FAM 19A4 can also increase the release of reactive oxygen species （ROS） upon zymosan stimulation. Furthermore, based on receptor internalization, radio ligand binding assays and receptor blockage, we demonstrated for the first time that FAM19A4 is a novel ligand of formyl peptide receptor 1 （FPR1）. The above data indicate that upon inflammatory stimulation, monocyte/macrophage-derived FAM 19A4 may play a crucial role in the migration and activation of macrophages during pathogenic infections.