Bone tissue, lyophilized and stored at room temperature for 15 days or more, is not capable of transmitting HIV, HCV or HBV. Cell Tissue Bank. 2011;12:99-104. [PMID: 20361356 DOI: 10.1007/s10561-010-9173-9]

Risk assessment of hepatitis E transmission through tissue allografts

Hepatitis E virus (HEV) is a small non-enveloped single stranded RNA virus whose genotypes 3 and 4 have been associated with zoonotic transmission in industrialized countries. HEV infection is considered the main cause of acute hepatitis worldwide. In some cases, transfusion of blood components or organ transplantation have been reported as the source of infection. We have conducted a literature review on the risk of transmission through cell and tissue allografts. Although no case was found, measures to control this risk should be taken when donor profile (based upon geographical and behavioural data) recommended it. Issues to be considered in donor screening and tissue processing to assess and to reduce the risk of HEV transmission are approached.

Effect of different human tissue processing techniques on SARS-CoV-2 inactivation-review

The safety of the tissue transplant recipient is a top priority for tissue banks, and the emergence of the new coronavirus SARS-CoV-2 has raised significant concerns about the risks of releasing tissue for clinical use. In the present study, we conducted a literature review about the potential infectivity of SARS-CoV-2 in different biological tissues and the influence of various tissue processing and sterilization procedures on viral inactivation. The search revealed that SARS-CoV-2 binds to the human angiotensin-converting enzyme receptor to penetrate human cells. These receptors are present in skin cells, musculoskeletal tissue, amniotic membranes, cardiovascular tissue and ocular tissues, including the cornea. In general, we found that coronaviruses are stable at low temperatures, and inactivated upon exposure to extreme heat and pH. Notably, gamma irradiation, which has already been employed to inactivate SARS and MERS, could be useful for sterilizing skin, amnion and musculoskeletal tissues against SARS-CoV-2. We conclude that due to the limited information about the effects of physical and chemical tissue processing methods on viral neutralization, rigorous donor screening is still essential for tissue transplant recipient safety.

The emergence and pitfalls of international tissue banking

The rapid growth of tissue banking and associated international organisations following the fall of the Berlin wall in 1991 is described. This surge in collaboration led to a world-wide constructive movement to use and to produce human tissues. As the years progressed industrialisation, led by the USA, improved the quality of tissue allografts but led higher costs and consolidation within the developing industry. The growth of litigation more than kept pace with the industrial progress. One landmark case is described, the outcome of which could revolutionise the current practices now applied to eliminate possible viral contamination of implanted tissue grafts.

Hepatitis B transmission by cell and tissue allografts: How safe is safe enough?

More than 2 million human tissue transplants (bone, tendon, cartilage, skin, cornea, amniotic membrane, stem cells, heart valve, blood vessel, etc.), are performed worldwide every year. Cells and tissues are shared between countries which have different regulations and laboratory equipment and represent a risk of hepatitis B virus (HBV) transmission that has become a global safety concern. While the risk of transfusion-transmitted HBV infection from blood donations has been estimated, the rate of HBV transmission from donors to recipients of allografts is unknown and varies between different tissues. There are various important ways of reducing the transmission risk, but donor screening and donor testing are still the main factors for preventing HBV transmission. HBV detection is included in the routine screening tests for cell and tissue donors. The standard test for preventing transplant-transmitted hepatitis B is the hepatitis B surface antigen. The implementation of methods involving nucleic acid amplification and the new generation of reactives to detect viral antibodies or antigens with an immunoassay, has increased the sensitivity and the specificity of the screening tests. The objective of our research was to review the literature and critically analyse the different steps for avoiding HBV transmission in cell and tissue donors, focusing on the screening tests performed.

A quantitative polymerase chain reaction test to enumerate leukocytes in allograft tissue and the implications for donor eligibility testing

A country-to-country analysis of infectious disease screening requirements for donated tissues or cells reveals they are not often harmonized. Transmission of one such infectious disease, human T-lymphotropic virus (HTLV), is related to the transfer of HTLV-infected, viable leukocytes of sufficient number. The ability to characterize allograft tissue as being absent of leukocytes, or containing relatively few leukocytes, by using a specific test has not been previously investigated. A quantitative polymerase chain reaction (qPCR) test was developed to interrogate protein tyrosine phosphatase, receptor type C (PTPRC) gene expression in tissue samples and was able to determine the number of leukocytes present in a tissue. The impact of a qualified leukocyte tissue testing method should be significant and lead to changes in donor eligibility regulations in certain countries. Human leukapheresis samples were used as a control to establish the amount of PTPRC in leukocytes. That value was used as a comparator to determine the number of leukocyte equivalents in tissues of interest. The qPCR test measured tissue leukocyte equivalents and the results were consistent with the relative abundance of leukocytes predicted for each tissue. Using qPCR to calculate leukocyte equivalents based upon PTPRC gene expression can be successfully employed to estimate the number of leukocytes in a tissue or allograft. This method could be used as a screen to rule out tissues that do not meet the criteria of being leukocyte rich and, therefore, do not need direct HTLV testing.