Abstract Cathelicidin host defense peptides (cHDPs) widely exist in animals with the functions of innate immunity and acquired immunity. To investigate the tissue and sequential expression patterns of the dCATH gene, which encodes the only cHDPs found in waterfowls, we analyzed the internal organs of healthy ducks (Shaxoxing Sheldrake) from 1-day-old to 28-day-old raised in the natural environment. The dCATH mRNA expression level across tissues was determined via quantitative real-time polymerase chain reaction (qRT-PCR). Monoclonal antibody against the mature dCATH peptide used in enzyme-linked immunosorbent assay (ELISA) was prepared by the lymphocyte hybridoma technique for the first time. The concentration of the dCATH peptide in tissues was determined by ELISA. It showed that the dCATH mRNA had a clear tissue-specificity and age-dependent expression pattern, and it was highly expressed in the bone marrow and moderately expressed in the liver, kidney, spleen, pancreas and bursa of healthy duck. The peptide levels of dCATH in liver, kidney, spleen, pancreas and bursa changed with the age of duck, and the peptide concentration in these organs was between 88 and 128 ng/g tissue. For the first time, we characterized the concentration of the cHDP dCATH in vivo. Our study may represent new insights into the crosstalk of innate immunity, tissue development and age.

中文翻译：

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鸭嘴兽宿主防御肽dCATH的组织表达分布特征

摘要 导管素宿主防御肽（cHDPs）广泛存在于动物体内，具有先天免疫和获得性免疫功能。为了研究 d​​CATH 基因的组织和序列表达模式，该基因编码在水禽中发现的唯一 cHDP，我们分析了自然饲养 1 日龄至 28 日龄的健康鸭（沙克星雪鸭）的内脏。环境。通过定量实时聚合酶链反应 (qRT-PCR) 确定组织中的 dCATH mRNA 表达水平。酶联免疫吸附试验(ELISA)中使用的针对成熟dCATH肽的单克隆抗体是首次采用淋巴细胞杂交瘤技术制备。通过ELISA测定组织中dCATH肽的浓度。表明dCATH mRNA具有明显的组织特异性和年龄依赖性表达模式，在健康鸭的骨髓中高表达，在肝、肾、脾、胰腺和法氏囊中适度表达。肝脏、肾脏、脾脏、胰腺和法氏囊中dCATH的肽水平随鸭龄而变化，这些器官中的肽浓度在88-128 ng/g组织之间。我们首次表征了体内 cHDP dCATH 的浓度。我们的研究可能代表对先天免疫、组织发育和年龄之间的串扰的新见解。胰腺和法氏囊随着鸭的年龄而变化，这些器官中的肽浓度在 88 至 128 ng/g 组织之间。我们首次表征了体内 cHDP dCATH 的浓度。我们的研究可能代表对先天免疫、组织发育和年龄之间的串扰的新见解。胰腺和法氏囊随着鸭的年龄而变化，这些器官中的肽浓度在 88 至 128 ng/g 组织之间。我们首次表征了体内 cHDP dCATH 的浓度。我们的研究可能代表对先天免疫、组织发育和年龄之间的串扰的新见解。