ABSTRACT
Since the first FDA approval of Lamivudine in 1998, many nucleo(t)side analogs such as Lamivudine, Adefovir, and Entecavir have been used. However, they only inhibit DNA synthesis, and if their administration is stopped a viral breakthrough can develop, making long-term administration necessary, ultimately followed by the development of resistance. Tenofovir has been developed and drug-resistant mutations have decreased significantly, but the problem of resistance due to long-term drug use still remains, along with the drug safety problem. In this review, we introduce the recent trend in the development of hepatitis B treatment agents and the Korea National Research Institute of Health (KNIH) research for the development of a novel treatment for hepatitis B (drug repositioning) without resistance and which targets the various life cycles of HBV.
ABSTRACT
Hepatitis B virus (HBV) infection is a major public health problem, with some 250 million people currently at high risk of developing chronic liver diseases. The current antiviral treatment for chronic hepatitis B (CHB) is effective in controlling viral replication but fails to achieve a complete cure. Since the identification of sodium taurocholate cotransport polypeptide (NTCP) as an HBV receptor, anti-HBV drugs targeting viral entry, capsid assembly, cccDNA, transcription, and secretion have been developed. In this paper, the potential inhibitors in various steps of the HBV life cycle are summarized.
ABSTRACT
Since the first FDA approval of Lamivudine in 1998, many nucleo(t)side analogs such as Lamivudine, Adefovir, and Entecavir have been used. However, they only inhibit DNA synthesis, and if their administration is stopped a viral breakthrough can develop, making long-term administration necessary, ultimately followed by the development of resistance. Tenofovir has been developed and drug-resistant mutations have decreased significantly, but the problem of resistance due to long-term drug use still remains, along with the drug safety problem. In this review, we introduce the recent trend in the development of hepatitis B treatment agents and the Korea National Research Institute of Health (KNIH) research for the development of a novel treatment for hepatitis B (drug repositioning) without resistance and which targets the various life cycles of HBV.
ABSTRACT
Hepatitis B virus (HBV) infection is a major public health problem, with some 250 million people currently at high risk of developing chronic liver diseases. The current antiviral treatment for chronic hepatitis B (CHB) is effective in controlling viral replication but fails to achieve a complete cure. Since the identification of sodium taurocholate cotransport polypeptide (NTCP) as an HBV receptor, anti-HBV drugs targeting viral entry, capsid assembly, cccDNA, transcription, and secretion have been developed. In this paper, the potential inhibitors in various steps of the HBV life cycle are summarized.
ABSTRACT
BACKGROUND: Research on RBC production from hematopoietic stem cells has been conducted competitively in many countries. However those were in vitro successes and many hurdles still remain for large scale transfusable RBC production from stem cells. A need for large volume of culture media is a crucial factor for culture condition which researchers must overcome. In this study, we evaluated the efficiency of two commercial serum-free media, StemPro(R)-34 SFM and Stemline II hematopoietic stem cell expansion medium, in RBC differentiation from cord derived stem cells. METHODS: We cultured cord derived CD34+ cells in vitro and evaluated over the periods of 7 days, 14 days, 17 days and 21 days in culture for expanded cell count, cell morphology and differential count using the Wright Giemsa stain. RESULTS: Cell expansion and RBC differentiation developed rapidly in Stemline media compared to StemPro media. Enucleated RBCs were observed at 10~14 culture days and orthochromatic erythroblasts were shown up to 50% among culture cells at 17 days in Stemline media. The enucleated RBCs were observed at 17 days in StemPro Media. Although the erythroblasts in StemPro media are slow at differentiation, they maintain continuous expansion up to 21 days. CONCLUSION: In Stemline media, the expansion and differentiation to mature RBCs are processed much faster, but the cell condition slows down after 17 days. In the RBC production aspects, Stemline media is better than StemPro media as a rapid differentiation because it reduces the cost due to in vitro short culture duration.