The Use of Human Tissues in Research: A Summary

There have been several high-profile legal cases which have ended in the removal of human biospecimens from research teams. One case resulted in the destruction of more than 5 x 106 dried blood spots that were obtained from infants after a suit challenged the state of Texas’ right to store these blood spots for future research. All these cases have one thing in common: the argument whether participants were properly informed regarding how their samples will be used for research. Informed consent is being increasingly discussed not only by professionals but also by the public. These cases have also prompted discussions regarding the timing and type of consent required, use of samples, and more.

This article highlights the opinions of the following experts who all represent different viewpoints on informed consent:

• David S. Wendler (D): Advocate for rights of research donors

• Arthur L. Caplan (A): Bioethicist

• Michael Christman (M): President and Chief Executive Officer (CEO) for an independent non-profit biomedical research institution with a large biorepository

• Jack Moye Jr. (J): Researcher

Is consent necessary or do you prefer a presumed consent with an opt-out option with the idea that human biospecimens should be a common heritage that is used for the collective good?

David: The tissues are not just “a collective good”. Tissues are obtained from specific individuals with their use involving the interests of donors and participants. Some of the things to keep in mind include the risks involved when obtaining samples, privacy, contribution, and use of the sample in future research. The necessity of obtaining consent allows donors to decide if they are willing to face the risks involved, increase awareness of the possibility of new information, and the advantages of contributions.

Arthur: The efforts taken to obtain informed consent are doomed to failure as there are many programs that use open-ended informed consent forms that are incomplete and vague. There are also those that ask donors or participants to waive their commercial interest such as the use of blanket waivers. A more appropriate way would be through altruistic gifting. This means that the specimens are made a gift making it clear that commercial interest is forgone, the use of specimen is open-ended, and possession has been transferred to a third party. A presumed consent to gifting would make more sense as long as patients retain the ability to opt out of gifting.

Michael: Current specimens that are anonymous should be allowed for use by research without the need of consent as there identification of donors will not be required. While studies that use anonymous specimens are usually exempted from the institutional review board (IRB) review, proper regulations should be implemented to ensure that this is upheld. However, an exception should be made for the use of anonymous specimens in genomic research as there is a possibility of identification.

Jack: The concept of human biospecimens as a shared resource for the collective good is a fascinating idea that should be given more attention. A framework where human tissue is a common heritage of humanity that is to be used for the collective good can help prevent disputes about both specimens that are left over from clinical purposes and those obtained for research.
What type of informed consent is best: general permission, tiered consent, specific consent, or other?

David: Many studies have been conducted regarding individuals’ attitudes about consent. They have consistently observed that the majority of donors want to control if their samples are used for research. Most participants are also willing to contribute when asked. These studies have also found that most donors support one-time general consent with the understanding that future use will require a review and approval from the ethics review committee such as the IRB. A widespread support shows that the one-time general consent offers the choice most donors would make. It also offers an opportunity to decline from contributing for those unwilling to contribute or for those who want more specific control over their specimens.

Arthur: A tiered consent would outline the likely uses of the specimen, disposition of materials, policy regarding the sale of material to third parties, transfer of control, and availability of clinical findings that would be relevant to donors.

Michael: A consent menu that has multiple choices would be best. A study found that although 10 percent support the consenting menu, most prefer 48 percent of blanket consent while the rest (42 percent) prefer re-consenting when a new research project begins.

Jack: Specific consent would help provide assurances that both the participants and researchers are equal in the enterprise. It is also easily accomplished when samples are obtained for a specific project. However, it can become impractical if the samples are stored for long-term with undefined uses. Most participants that are based in the United States are willing to contribute their samples.

What about property rights to specimens? Should research participants share potential financial gain?

David: Generally, individuals should share the benefits to the project they contributed to. Failing to provide a fair level of benefit can be regarded as a case of exploitation. Since the samples are part of an important contribution, it would suggest that the participants should share the benefits such as financial gain from the research projects. However, this can become complicated in practice as it is unclear what is a fair level of benefit or how benefits can be provided.

Michael: As part of the consent process, participants should be informed about property rights, the potential for financial gain (for the investigator), and if they themselves will share any financial gain. Once the participant is aware before enrolled in the study, the allowing or disallowing of financial gain and property rights should be acceptable. Consent should not be waived in cases if there is expected financial gain for the investigator.

Jack: Unless the research is conducted with the objective of developing a commercial product, proprietary interest in research by the donors can be difficult. It can be hard to put a value on something that has yet to exist especially in cases where there is an assertion of property rights where there is litigation corresponding with perceived value.

References:
Gronowski AM, Moye J, Wendler DS, Caplan AL, Christman M. The use of human tissues in research: what do we owe the research subjects? Clinical Chemistry. 2011; 57 (4): 540-544.

Preanalytical Variables: Long-Term Storage and Retrieval of Biospecimens

Introduction

The week before last we talked about how pre-analytical variables affect the integrity of human biospecimens, and this week we’ll be following up on this article by discussing the long term storage and retrieval of biospecimens.

The term “storage” comprises of both short and long-term storage of all biospecimens consistent with the study design and planned future use. Depending on the details of their future use, the specimens are either locally or centrally stored. It can also be stored in both locations. The decision will be made depending on the:

• Sample size of biospecimens

• Complexity of collection

• The accrual rate of biospecimens

• Processing procedures

• Logistics

• Cost of storage and retrieval

• Quality issues

• Biorepository governance factors

If the biospecimens are stored for various uses, biorepositories should have duplicates that are close in proximity to the main laboratory. Samples that are to be stored for more than a year should be stored centrally. Duplicates should also be stored on different power supplies or different locations as insurance against natural disasters or equipment failure. Biorepositories are also recommended to have approximately 10 percent of the total mechanical freezers as empty backup freezers to protect against freezer failure. Different storage conditions may be required based on the downstream analyses. Some of the pre-analytical variables that affect long-term storage include:

• The time involved from processing to storage

• Duration of storage

• Temperature

• Facility

• Environmental impact (such as moisture, sunlight, dehydration, humidity, oxidation, evaporation, and desiccation)

• Freeze-thaw cycles

• Some emergencies include: encapsulation of biospecimens in ice after refreezing and microbiological contamination

• Destroyed or no labeling

• Missing or misplaced aliquots

Since biobank material is valuable and hard to replace, the use of systems such as the laboratory information management system (LIMS) should be utilized as it helps allow traceability, confirm chain of custody, and manage biospecimens to improve data reliability and retrieval. Once the integrity of a biospecimen is compromised, it is no longer valuable and becomes useless. It is therefore important to retrieve only those biospecimens that are required. As previously mentioned, duplicate collections of biospecimens are ideal to prevent the destruction of samples.

Blood Sample

The study of the stability of analytes compared to the fresh sample, taking into account the recovery rates, are vital to determine the effects of long-term storage. After long-term storage, the recovery rates may decrease or increase resulting in increased or attenuated risk ratios. It is recommended that hormone, chemistry, and protein analytes are much more stable and stored at -80⁰C for up to 13 months. However, various studies have shown that there are different patterns of stability based on the analyte, time, and temperature of storage. There has been no systematic influence regarding omics analyses observed in samples collected in citrate, heparin, or ethylenediamine triacetic acid (EDTA) if stored at -80⁰C in liquid nitrogen. Long term storage in room temperature and repeated freeze cycles must be avoided. At room, low, and ultra-low temperatures, the extraction of DNA from whole blood samples using bio stabilization technology yielded samples that are pure and that have integrity. Although live cells are stable at room temperature for as long as 48 hours, it should be cryopreserved or cultured in liquid nitrogen to ensure its viability. The recovery of sufficient DNA or those that are of acceptable quality for microarray studies involves the transfer of thawed buffy coat or EDTA whole blood into RNA preservative. Serum or plasma that will be used for miRNA analysis must be extracted immediately or maintained at -80 in RNA free cryotubes.

Urine Sample Protocol

For urine samples, long term storage at temperatures less than -80⁰C without additives is ideal unless it has been specified for certain downstream analyses. Urine samples have been stored at -22⁰C for 12 to 15 years without the use of preservatives while ensuring the stability and measurement validity. Urine used for metabolome and proteome analyses will go through progressive protein degradation if stored at room temperature. While freeze-thaw cycles have minimal impact on the protein profiles, repeated cycles should ideally be avoided.

Saliva Sample Protocol

The protocols for saliva storage are ultimately dependent on the expected downstream analyses. There seems to be minimal impact of protein profile changes despite freeze-thaw cycles. It is recommended that it is stored at -80⁰C. If the saliva samples were divided into aliquots and frozen immediately at -80⁰C, there does not seem to be any differences in cortisol, C-reactive protein, mRNA, or cytokines.

Extracted DNA Sample protocol

The most common method of storage for DNA is still freezing it at -80⁰C. It should be noted that DNA degradation increases with repeated freeze-thaw cycles, higher storage temperature, dilution, and multiple suspensions. Special technologies allow the minimization of storage space and the reduction of shipping and electrical costs. This can be beneficial especially when cryogenic or mechanical equipment is unavailable. It can also be an alternative method for backup storage. Using this technology, there is no degradation or accelerated aging of DNA at room temperature or higher temperatures (50-70⁰C) throughout the 8-month storage duration.

RNA sample protocol

Some of the pre-analytical storage factors that can affect the quality and quantity of analyte or gene expression include the concentration of RNA, temperature, storage time, and repeated thaws. New technology for the dry storage of RNA at room temperature has been developed. This is a technology comparable to RNA that is cryopreserved for up to a year for downstream analyses such as RNA sequencing and real-time polymerase chain reaction.

References:

Ellervik C, Vaught J. Preanalytical variables affecting the integrity of human biospecimens in biobanking. Clinical Chemistry. 2015; 61(7): 913-934. http://clinchem.aaccjnls.org/content/clinchem/61/7/914.full.pdf