Hepatocyte transplantation: past efforts, current technology, and future expansion of therapeutic potential.

Hepatic cell transplantation (HCT) continues to garner interest as an alternative to orthotopic liver transplantation and the attendant donor shortage. When compared with solid organ transplantation, advantages of cell transplantation include the potential to treat more patients with a considerably less invasive procedure, the ability to utilize organs otherwise unsuitable for transplant, and leaving the native organ in situ with the potential for regeneration. While studies date back to the early 1960s, advancement of clinical application has been slow due in part to limitations of suitable tissue supplies and reproducible robust techniques. Compared with orthotopic liver transplantation, there are fewer absolute contraindications for donor selection. And, current techniques used to harvest, isolate, store, and even transfuse cells vary little between institutions. Significant variation is seen due to a lack of consensus with maintenance therapy. Although the ideal recipient has not been clearly identified, the most significant results have been demonstrated with correction of congenital metabolic liver disorders, with a few trials examining its utility in cirrhotics and more recently acute liver failure. The most exciting new topic of discussion examines techniques to improve engraftment, with many such as ischemic preconditioning and nonselective partial embolization (microbead therapy), while not yet used in HCT study, showing promise in solid organ research. Advancements in HCT, although slow in progress, have great potential in the ability to alleviate the burden faced in solid organ transplantation and possibly become a long-term viable option, beyond that of a bridge or salvage therapy.

The History and Challenges of Blood Donor Screening in China.

Since the establishment of People's Republic of China in 1949, the Chinese government has encountered several catastrophes related to transfusion transmitted diseases. The government's increasing attention to blood safety has prompted the initiation of a series of policies and measures that have enhanced the level of safety for the blood supply and met the basic clinical demands of blood for 1.3 billion people in the country. Blood donation screening strategies in China predominantly comprise donor screening and donor testing. Donor screening includes selection of low-risk blood donors by the use of a donor history questionnaire, predonation physical examination, and initial rapid donor testing. Donor testing includes direct pathogen detection and serology tests. The year 1998 marked the most transformative change in blood donor selection and screening policies in China. Before 1998, paid donation was the predominant mode of blood donation. Donor screening and donor testing were conducted before donation, and only those who were eligible were allowed to donate. To ensure the safety of blood, donor testing was performed again after donation. After the implementation of the Blood Donation Law in 1998, to promote voluntary and unpaid donation, predonation donor testing was eliminated to reduce the amount of waiting time and to provide a more convenient donation experience for blood donors. However, it is the national requirement that donated blood should undergo 2 rounds of testing using different equipment or reagents, conducted by different personnel. Donor selection has transitioned from paid donation and obligatory donation to voluntary donation with fixed volunteer groups, as the latter mode of donation provides the lowest risks. Donations are currently screened for syphilis, hepatitis C virus, HIV, and hepatitis B virus (HBV). Units, previously typed only for ABO, are now routinely tested for both ABO and Rh(D). Innovations in testing technologies and methods have also brought changes to screening parameters. For instance, screening for HBV pathogens evolved from the early use of hemagglutination method to the later use of radioimmunoassay, independent enzyme-linked immunosorbent assay, and now the widespread application of nucleic acid test (NAT). Since 2010, the Chinese government has established NAT capacity in several blood centers; and in 2015, the government invested 900 million RMB on the nationwide expansion of NAT. Although the Chinese government has worked to enhance blood safety, many challenges remain. Concern exists for rising rates of HIV infection. The existence of occult HBV infection and the transmission of emerging blood-borne diseases continue to challenge the safety of the blood supply.