Interleukin-3 (IL-3), IL-5, and granulocyte-macrophage colony-stimulating factor (GM-CSF) are related cytokines that signal through receptors possessing the β common (βc) chain. As a family, these cytokines combine rather non-specific hematopoietic growth factor properties with a special importance for eosinophils, basophils, and mast cells. In fish the cytokines of this family are called IL-5fam, and the present study, using carp, constitutes their first functional analysis. Carp il-5fam expression was enhanced by stimulation with phytohemagglutinin and killed bacteria. Reminiscent of mammalian IL-3/IL-5/GM-CSF family members, recombinant carp IL-5fam (rcIL-5fam) induced activation of transcription factor STAT5 and efficiently promoted proliferation and colony-formation of eosinophil/basophil/mast-cell type (EBM) granulocytes. Upon addition of recombinant carp βc the growth effect of rcIL-5fam was reduced, suggesting βc participation in the signaling route. In summary, despite differences in individual cytokines and cell populations, fish and mammalian IL-3/IL-5/GM-CSF family members share growth factor functions for non-neutrophil granulocytes.

白细胞介素 3 (IL-3)、IL-5 和粒细胞-巨噬细胞集落刺激因子 (GM-CSF) 是相关的细胞因子，它们通过拥有 β 共同 (βc) 链的受体发出信号。作为一个家族，这些细胞因子结合了非特异性的造血生长因子特性，对嗜酸性粒细胞、嗜碱性粒细胞和肥大细胞具有特殊重要性。在鱼类中，该家族的细胞因子被称为 IL-5fam，本研究使用鲤鱼进行了首次功能分析。鲤鱼il-5fam通过用植物血凝素刺激和杀死细菌来增强表达。让人联想到哺乳动物 IL-3/IL-5/GM-CSF 家族成员，重组鲤鱼 IL-5fam (rcIL-5fam) 诱导转录因子 STAT5 激活并有效促进嗜酸性粒细胞/嗜碱性粒细胞/肥大细胞类型的增殖和集落形成(EBM) 粒细胞。添加重组鲤鱼 βc 后，rcIL-5fam 的生长效果降低，表明 βc 参与了信号通路。总之，尽管个体细胞因子和细胞群存在差异，但鱼类和哺乳动物 IL-3/IL-5/GM-CSF 家族成员共享非中性粒细胞的生长因子功能。