A novel transgenic mouse model of lysosomal storage disorder.
A novel transgenic mouse model of lysosomal storage disorder.
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溶酶体贮积症的新型转基因小鼠模型。
DOI：
10.1152/ajpgi.00313.2015
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
Rittenhouse,AnnR
中科院分区：
文献类型：
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作者：
Ortiz-Miranda,Sonia;Ji,Rui;Jurczyk,Agata;Aryee,Ken-Edwin;Mo,Shunyan;Fletcher,Terry;Shaffer,ScottA;Greiner,DaleL;Bortell,Rita;Gregg,RonaldG;Cheng,Alan;Hennings,LeahJ;Rittenhouse,AnnR
敲除技术已被证明对于描述特定基因的功能作用非常有用。在这里，我们描述并解释了在心脏 α-肌球蛋白重链启动子控制下表达大鼠 CaVβ2a 转基因的基因工程小鼠亚群中发生的惊人病理学。病变仅限于转基因纯合小鼠且与天然Cacnb2基因组拷贝数无关。总体检查结果包括胰腺萎缩；脂肪组织减少；增厚的橙色肠子；以及肝脏、脾脏和腹部淋巴结肿大。免疫细胞浸润和巨噬细胞吞噬细胞与胰腺腺泡细胞的损失相关。泡沫状巨噬细胞广泛浸润小肠固有层，而类似的巨噬细胞聚集体则聚集在肝脏和脾脏的红髓血窦中。高碘酸希夫阳性、淀粉酶抗性、铁阴性、油红 O 阳性和自发荧光细胞质表明存在脂质储存障碍。电子显微镜分析显示，肝窦因含有细胞内髓磷脂“漩涡”的巨噬细胞簇和具有增大的溶酶体的肝细胞而扩张。此外，胆固醇、胆固醇酯和甘油三酯的积累，以及肝脏代谢酶水平的变化，与脂质加工缺陷一致。由于这种复杂的病理学，我们检查了转基因插入位点。多个转基因拷贝插入19号染色体；在同一位点，发生了大约 180,000 个碱基对缺失，消除了胆固醇 25-羟化酶并部分删除了溶酶体酸性脂肪酶和 CD95。基因功能的丧失可以解释脂质加工的改变以及免疫系统的肥大，这定义了这种表型，并偶然提供了一种新的溶酶体贮积症小鼠模型。
Knockout technology has proven useful for delineating functional roles of specific genes. Here we describe and provide an explanation for striking pathology that occurs in a subset of genetically engineered mice expressing a rat CaVβ2a transgene under control of the cardiac α-myosin heavy chain promoter. Lesions were limited to mice homozygous for transgene and independent of nativeCacnb2genomic copy number. Gross findings included an atrophied pancreas; decreased adipose tissue; thickened, orange intestines; and enlarged liver, spleen, and abdominal lymph nodes. Immune cell infiltration and cell engulfment by macrophages were associated with loss of pancreatic acinar cells. Foamy macrophages diffusely infiltrated the small intestine's lamina propria, while similar macrophage aggregates packed liver and splenic red pulp sinusoids. Periodic acid-Schiff-positive, diastase-resistant, iron-negative, Oil Red O-positive, and autofluorescent cytoplasm was indicative of a lipid storage disorder. Electron microscopic analysis revealed liver sinusoids distended by clusters of macrophages containing intracellular myelin “swirls” and hepatocytes with enlarged lysosomes. Additionally, build up of cholesterol, cholesterol esters, and triglycerides, along with changes in liver metabolic enzyme levels, were consistent with a lipid processing defect. Because of this complex pathology, we examined the transgene insertion site. Multiple transgene copies inserted into chromosome 19; at this same site, an approximate 180,000 base pair deletion occurred, ablatingcholesterol 25-hydroxylaseand partially deletinglysosomal acid lipaseandCD95. Loss of gene function can account for the altered lipid processing, along with hypertrophy of the immune system, which define this phenotype, and serendipitously provides a novel mouse model of lysosomal storage disorder.