Department of Clinical Research, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.
PLoS Negl Trop Dis. 2013;7(3):e2117. doi: 10.1371/journal.pntd.0002117. Epub 2013 Mar 14.
Trachoma is a fibrotic disease of the conjunctiva initiated by Chlamydia trachomatis infection. This blinding disease affects over 40 million people worldwide yet the mechanisms underlying its pathogenesis remain poorly understood. We have investigated host microRNA (miR) expression in health (N) and disease (conjunctival scarring with (TSI) and without (TS) inflammation) to determine if these epigenetic differences are associated with pathology.
We collected two independent samples of human conjunctival swab specimens from individuals living in The Gambia (n = 63 & 194). miR was extracted, and we investigated the expression of 754 miR in the first sample of 63 specimens (23 N, 17 TS, 23 TSI) using Taqman qPCR array human miRNA genecards. Network and pathway analysis was performed on this dataset. Seven miR that were significantly differentially expressed between different phenotypic groups were then selected for validation by qPCR in the second sample of 194 specimens (93 N, 74 TS, 22 TSI).
Array screening revealed differential expression of 82 miR between N, TS and TSI phenotypes (fold change >3, p<0.05). Predicted mRNA targets of these miR were enriched in pathways involved in fibrosis and epithelial cell differentiation. Two miR were confirmed as being differentially expressed upon validation by qPCR. miR-147b is significantly up-regulated in TSI versus N (fold change = 2.3, p = 0.03) and miR-1285 is up-regulated in TSI versus TS (fold change = 4.6, p = 0.005), which was consistent with the results of the qPCR array.
miR-147b and miR-1285 are up-regulated in inflammatory trachomatous scarring. Further investigation of the function of these miR will aid our understanding of the pathogenesis of trachoma.
沙眼是由沙眼衣原体感染引起的结膜纤维化疾病。这种致盲疾病影响全球超过 4000 万人，但发病机制仍知之甚少。我们研究了健康（N）和疾病（有（TSI）和无（TS）炎症的结膜瘢痕）中宿主 microRNA（miR）的表达，以确定这些表观遗传差异是否与病理学有关。
我们从冈比亚的个体中收集了两个独立的人结膜拭子标本样本（n = 63 和 194）。提取 miR，我们使用 Taqman qPCR 阵列人类 miRNA genecards 对来自 63 个标本中的第一组样本（23 个 N，17 个 TS，23 个 TSI）的 754 个 miR 的表达进行了研究。对该数据集进行了网络和途径分析。然后，从第二组 194 个标本（93 个 N，74 个 TS，22 个 TSI）中选择了 7 个在不同表型组之间差异表达的 miR 进行 qPCR 验证。
阵列筛选显示，N、TS 和 TSI 表型之间有 82 个 miR 的表达差异（倍数变化>3，p<0.05）。这些 miR 的预测 mRNA 靶标富集在纤维化和上皮细胞分化途径中。两种 miR 通过 qPCR 验证被确认为差异表达。miR-147b 在 TSI 与 N 相比显著上调（倍数变化=2.3，p=0.03），miR-1285 在 TSI 与 TS 相比上调（倍数变化=4.6，p=0.005），与 qPCR 阵列的结果一致。
miR-147b 和 miR-1285 在炎症性沙眼瘢痕中上调。进一步研究这些 miR 的功能将有助于我们了解沙眼的发病机制。
