Genetic diversity of nucleocapsid genes of recent porcine epidemic diarrhea viruses isolated in Korea

Porcine epidemic diarrhea virus (PEDV), a porcine enteropathogenic coronavirus, causes lethal watery diarrhea in piglets, resulting in large economic losses because of high mortality. In November 2013, PEDV reemerged in Korea, and these outbreaks have since continuously occurred. In the present study, we determined the full-length nucleocapsid (N) gene sequences of three Korean PEDV field isolates collected in 2014-2015. Sequence and phylogenetic analysis of N genes revealed that recent prevalent Korean PEDV isolates were very closely related to the US PEDV isolates in 2013. Interestingly, the phylogenetic tree based on the nucleotide sequencing of the PEDV N gene was similar to the tree topology of the PEDV complete genomes. Therefore, our data provide a better understanding of the genetic diversity and contribute to the accurate diagnosis and development of vaccines against PEDV.

Hematopoietic stem cell expansion and generation: the ways to make a breakthrough

Hematopoietic stem cell transplantation (HSCT) is the first field where human stem cell therapy was successful. Flooding interest on human stem cell therapy to cure previously incurable diseases is largely indebted to HSCT success. Allogeneic HSCT has been an important modality to cure various diseases including hematologic malignancies, various non-malignant hematologic diseases, primary immunodeficiency diseases, and inborn errors of metabolism, while autologous HSCT is generally performed to rescue bone marrow aplasia following high-dose chemotherapy for solid tumors or multiple myeloma. Recently, HSCs are also spotlighted in the field of regenerative medicine for the amelioration of symptoms caused by neurodegenerative diseases, heart diseases, and others. Although the demand for HSCs has been growing, their supply often fails to meet the demand of the patients needing transplant due to a lack of histocompatible donors or a limited cell number. This review focuses on the generation and large-scale expansion of HSCs, which might overcome current limitations in the application of HSCs for clinical use. Furthermore, current proof of concept to replenish hematological homeostasis from non-hematological origin will be covered.