Analysis of Influenza A virus infection in human induced pluripotent stem cells (hiPSCs) and their derivatives.

Influenza A virus (IAV) infection in pregnant women is a major public health concern. However, the effect of IAV infection on human embryogenesis is still unclear. Here we show that human induced pluripotent stem cells (hiPSCs) and hiPSC-derived ectodermal, mesodermal and endodermal cells are susceptible to IAV infection. These cell types stained positive for α2,6-linked sialic acid, the receptor for IAV infection expressed on the cell surface. While hiPSCs produced high viral titers for up to 7 days with increasing infected cell number suggesting that the viral progenies produced from hiPSCs without exogenous protease were infectious and could spread to other cells, the three germ-layer cells showed a decline in viral titers suggesting the lack of viral spreading. Amongst the three germ layers, endodermal cells were less susceptible than ectodermal and mesodermal cells. These results indicate the permissiveness of cells of early embryogenesis, and suggest a risk of detrimental effects of IAV infection in early human embryonic development.

Plasma microRNA-451 as a novel hemolytic marker for ß0-thalassemia/HbE disease.

In Southeast Asia, particularly in Thailand, ß0-thalassemia/hemoglobin E (HbE) disease is a common hereditary hematological disease. It is associated with pathophysiological processes, such as the intramedullary destruction of immature erythroid cells and peripheral hemolysis of mature red blood cells. MicroRNA (miR) sequences, which are short non-coding RNA that regulate gene expression in a suppressive manner, serve a crucial role in human erythropoiesis. In the present study, the plasma levels of the erythroid-expressed miRNAs, miR­451 and miR­155, were analyzed in 23 patients with ß0-thalassemia/HbE and 16 control subjects. Reverse transcription­quantitative polymerase chain reaction analysis revealed significantly higher levels of plasma miR­451 and miR­155 in ß0­thalassemia/HbE patients when compared to the control subjects. Notably, among the ß0­thalassemia/HbE patients, a significant increase in miR­451 levels was detected in severe cases when compared with mild cases. The levels of plasma miR­451 correlated with reticulocyte and platelet counts. The results suggest that increased plasma miR­451 levels may be associated with the degree of hemolysis and accelerated erythropoiesis in ß0­thalassemia/HbE patients. In conclusion, miR­451 may represent a relevant biomarker for pathological erythropoiesis associated with ß0-thalassemia/HbE.