■胃富含亮氨酸重复序列的G蛋白偶联受体5(Lgr5)细胞在损伤和稳态过程中发挥重要功能。骨形态发生蛋白(BMP)信号调节胃部炎症和上皮稳态。我们调查了BMP信号传导是否控制炎症期间Lgr5+ve细胞的命运。
■使用H+/K+-腺苷三磷酸酶β亚基启动子在胃中表达BMP抑制剂noggin(Nog)(H+/K+-Nog小鼠)。通过将Lgr5-EGFP-ires-CreERT2(Lgr5-Cre)小鼠与具有BMP受体1A的浮动等位基因的小鼠(Lgr5-Cre;Bmpr1aflox/flox小鼠)杂交,可以抑制Lgr5细胞中的BMP信号传导。使用流式细胞术分离Lgr5/GFP+ve细胞。通过将Lgr5-Cre小鼠与表达Nog和tdTomato(Lgr5-Cre;H+/K+-Nog;Rosa26-tdTom)的小鼠杂交进行谱系追踪研究。使用非幽门螺杆菌感染诱发炎症。通过H&E染色分析粘膜的形态。H+/K+-三磷酸腺苷的分布IF-,Ki67-,CD44-,CD44v9-,通过免疫染色分析溴脱氧尿苷阳性细胞。通过分别用凝集素Griffonia(Bandeiraea)简单凝集素II和Ulexeuropaeus凝集素1染色来确定颈部和凹坑细胞粘蛋白的表达。Id1,Bmpr1a,Lgr5c-Myc,通过定量逆转录聚合酶链反应测量Cd44信使RNA。
■Lgr5-Cre;Bmpr1aflox/flox小鼠在Lgr5/GFPve细胞中显示Bmpr1a的表达减少。感染Lgr5-Cre;Bmpr1aflox/flox小鼠与Hfelis导致增强的炎症,细胞增殖增加,壁细胞丢失,以及化生和异型增生的发展。感染Lgr5-Cre;H+/K+-Nog;Rosa26-tdTom小鼠,但不能控制老鼠,显示存在番茄+ve腺体内衬较小的曲率,被Griffonia(Bandeiraea)simplifolia凝集素II和Ulexeuropaeus凝集素1和抗IF染色阳性,-CD44、-CD44v9和-溴脱氧尿苷抗体。
■炎症和BMP信号的抑制激活Lgr5+ve细胞,这导致了化生,发育不良,表达粘液颈部和酶原细胞分化标记的增殖谱系。
UNASSIGNED: Gastric Leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) cells exert important functions during injury and homeostasis. Bone morphogenetic protein (BMP) signaling regulates gastric inflammation and epithelial homeostasis. We investigated if BMP signaling controls the fate of Lgr5+ve cells during inflammation.
UNASSIGNED: The H+/K+-adenosine triphosphatase β-subunit promoter was used to express the BMP inhibitor noggin (Nog) in the stomach (H+/K+-Nog mice). Inhibition of BMP signaling in Lgr5 cells was achieved by crossing Lgr5-EGFP-ires-CreERT2 (Lgr5-Cre) mice to mice with floxed alleles of BMP receptor 1A (Lgr5-Cre;Bmpr1aflox/flox mice). Lgr5/GFP+ve cells were isolated using flow cytometry. Lineage tracing studies were conducted by crossing Lgr5-Cre mice to mice that express Nog and tdTomato (Lgr5-Cre;H+/K+-Nog;Rosa26-tdTom). Infection with Helicobacter felis was used to induce inflammation. Morphology of the mucosa was analyzed by H&E staining. Distribution of H+/K+-adenosine triphosphatase-, IF-, Ki67-, CD44-, CD44v9-, and bromodeoxyuridine-positive cells was analyzed by immunostaining. Expression of neck and pit cell mucins was determined by staining with the lectins Griffonia (Bandeiraea) simplicifolia lectin II and Ulex europaeus agglutinin 1, respectively. Id1, Bmpr1a, Lgr5, c-Myc, and Cd44 messenger RNAs were measured by quantitative reverse-transcription polymerase chain reaction.
UNASSIGNED: Lgr5-Cre;Bmpr1aflox/flox mice showed diminished expression of Bmpr1a in Lgr5/GFP+ve cells. Infection of Lgr5-Cre;Bmpr1aflox/flox mice with H felis led to enhanced inflammation, increased cell proliferation, parietal cell loss, and to the development of metaplasia and dysplasia. Infected Lgr5-Cre;H+/K+-Nog;Rosa26-tdTom mice, but not control mice, showed the presence of tomato+ve glands lining the lesser curvature that stained positively with Griffonia (Bandeiraea) simplicifolia lectin II and Ulex europaeus agglutinin 1, and with anti-IF, -CD44, -CD44v9, and -bromodeoxyuridine antibodies.
UNASSIGNED: Inflammation and inhibition of BMP signaling activate Lgr5+ve cells, which give rise to metaplastic, dysplastic, proliferating lineages that express markers of mucus neck and zymogenic cell differentiation.