Biological, Medical, and Other Tissue Variables Affecting Biospecimen Utilization

The power of light - From dental materials processing to diagnostics and therapeutics

Harnessing the power of light and its photonic energy is a powerful tool in biomedical applications. Its use ranges from biomaterials processing and fabrication of polymers to diagnostics and therapeutics. Dental light curable materials have evolved over several decades and now offer very fast (≤ 10 s) and reliable polymerization through depth (4-6 mm thick). This has been achieved by developments on two fronts: (1) chemistries with more efficient light absorption characteristics (camphorquinone [CQ], ~30 L mol-1 cm1 [ʎmax 470 nm]; monoacylphosphine oxides [MAPO], ~800 L mol-1 cm-1 [ʎmax 385 nm]; bisacylphosphine oxide [BAPO], ~1,000 L mol-1 cm-1 [ʎmax 385 nm]) as well mechanistically efficient and prolonged radical generation processes during and after light irradiation, and; (2) introducing light curing technologies (light emitting diodes [LEDs] and less common lasers) with higher powers (≤ 2 W), better spectral range using multiple diodes (short: 390-405 nm; intermediate: 410-450 nm; and long: 450-480 nm), and better spatial power distribution (i.e. homogenous irradiance). However, adequate cure of materials falls short for several reasons, including improper selection of materials and lights, limitations in the chemistry of the materials, and limitations in delivering light through depth. Photonic energy has further applications in dentistry which include transillumination for diagnostics, and therapeutic applications that include photodynamic therapy, photobiomodulation, and photodisinfection. Light interactions with materials and biological tissues are complex and it is important to understand the advantages and limitations of these interactions for successful treatment outcomes. This article highlights the advent of photonic technologies in dentistry, its applications, the advantages and limitations, and possible future developments.

Impact of Cold Ischemia on the Stability of 1H-MRS-Detected Metabolic Profiles of Ovarian Cancer Specimens

Proton magnetic resonance spectroscopy (1H-MRS) of surgically collected tumor specimens may contribute to investigating cancer metabolism and the significance of the "total choline" (tCho) peak (3.2 ppm) as malignancy and therapy response biomarker. To ensure preservation of intrinsic metabolomic information, standardized handling procedures are needed. The effects of time to freeze (cold ischemia) were evaluated in (a) surgical epithelial ovarian cancer (EOC) specimens using high-resolution (HR) 1H-MRS (9.4 T) of aqueous extracts and (b) preclinical EOC samples (xenografts in SCID mice) investigated by in vivo MRI-guided 1H-MRS (4.7 T) and by HR-1H-MRS (9.4 T) of tumor extracts or intact fragments (using magic-angle-spinning (MAS) technology). No significant changes were found in the levels of 27 of 29 MRS-detected metabolites (including the tCho profile) in clinical specimens up to 2 h cold ischemia, besides an increase in lysine and a decrease in glutathione. EOC xenografts showed a 2-fold increase in free choline within 2 h cold ischemia, without further significant changes for any MRS-detected metabolite (including phosphocholine and tCho) up to 6 h. At shorter times (≤1 h), HR-MAS analyses showed unaltered tCho components, along with significant changes in lactate, glutamate, and glutamine. Our results support the view that a time to freeze of 1 h represents a safe threshold to ensure the maintenance of a reliable tCho profile in EOC specimens.

Effects of donor source on transcriptomic profiles of human kidney tissue

Normal human tissue is a critical reference control in biomedical research. However, the type of tissue donor can significantly affect the underlying biology of the samples. We investigated the impact of tissue donor source type by performing transcriptomic analysis on healthy kidney tissue from three donor source types: cadavers, organ donors, and normal-adjacent tissue from surgical resections of clear cell renal cell carcinomas, and we compared the gene expression profiles to those of clear cell renal cell carcinoma samples. Comparisons among the normal samples revealed general similarity, with notable differences in gene expression pathways involving immune system and inflammatory processes, response to extracellular stimuli, ion transport, and metabolism. When compared to tumors, the transcriptomic profiles of the normal adjacent tissue were highly similar to the profiles from cadaveric and organ donor tissue samples, arguing against the presence of a field cancerization effect in clear cell renal cell carcinoma. We conclude that all three normal source types are suitable for reference kidney control samples, but important differences must be noted for particular research areas and tissue banking strategies.

The Use of Human Tissues for Research: What Investigators Need to Know

While laboratory animals are necessary for some aspects of the development of scientific and biomedical advances, including those of precision medicine, the use of human tissues is necessary in order to explore the findings and ensure that they are relevant to human systems. Many sources of human tissues exist, but researchers - particularly those making the transition from animal to human systems - may not be aware of how best to find quality sources of human tissues or how best to use them in their research. In this article, we discuss the advantages of using human tissues in research. In addition, we highlight some of the major advances made possible through the use of human tissue, and describe how human tissue is collected for research. We discuss the various types of bioresources that make human tissue available, and advise on how investigators can find and use appropriate bioresources to support their research - with the hope that this information will help facilitate the transition from research on animals to research using human tissues, as rapidly as is practicable.

Profiling classical neuropsychiatric biomarkers across biological fluids and following continuous lumbar puncture: A guide to sample type and time

Identification of putative biomarkers for neuropsychiatric disorders has produced a diverse list of analytes involved in inflammation, hypothalamic–pituitary–adrenal axis (HPA) regulation, growth factor and metabolic pathways. However, translation of these findings to accurate and robust assays has been stalled, affecting objective diagnoses, tracking relapse/remission, and prediction/monitoring of drug affect. Two important factors to control are the sample matrix (e.g. serum, plasma, saliva, or cerebrospinal fluid) and time of sample collection. Additionally, sample collection procedures may affect analyte level. In this study, a panel of 14 core neuropsychiatric biomarkers was measured in serum, plasma, saliva, and cerebrospinal fluid (CSF), all collected from 8 healthy volunteers at the same time. In a second cohort of 7 healthy volunteers, 6 analytes were measured in serum and CSF collected at 13 timepoints over a 24-h period after catheter placement. We found that many of the analytes were quantifiable in all sample types examined, but often at quite different concentrations and without correlation between the sample types. After catheter placement, a diurnal pattern was observed for cortisol and interleukin-6 in serum, and transient spikes were observed in interleukin-1β. In CSF, a chronic elevation of several cytokines was observed instead, perhaps due to the continuous sampling procedure. These findings enable more informed decision-making around sample type and collection time, which can be implemented in future biomarker studies.

Clinicaltrial.gov identifiers

NCT02933762, NCT02475148.

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Diurnal pattern for cortisol, interleukin (IL)-6 and transient spikes for IL-1β were observed

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Chronic elevation of cytokines observed may be due to continuous sampling procedure

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Informed decision-making around sample types and collection time can be implemented

Analysis of Trends in Biospecimen Complexity in Cancer Research Over Two Decades

Background: Over time, researchers' demand for increased quality and quantity of biospecimens has risen. However, quality is multifaceted, ranging from simple to complex, and comes at a cost. Therefore, to be sustainable and ensure optimal utilization of their resources (supply), biobanks must consider the trends in biospecimen use to predict the needs for future biospecimen quality (demand). Methods: An unbiased selection process was used to identify research articles from across the spectrum of cancer research from the PubMed database. A set of 225 articles utilizing human biospecimens were randomly selected for review (75 articles from each of three time intervals; 2000, 2010, 2020). Criteria for determining the source and complexity of quality of biospecimens were developed and overall concordance between two independent observers abstracting the data was then confirmed (k = 0.87) to validate the criteria. Results: We observed increased use of dual biospecimen formats (20%-36% of articles, p = 0.03), matched samples (16%-37% of articles, p = 0.0033), and biospecimens with associated outcomes data (20%-49%, p = 0.0002). In addition, the use of two or more cohorts increased over time (p = 0.03). The mechanism through which biospecimens were obtained also changed over time with an increase in the diversity of collection pathways used (p = 0.006). Conclusions: The complexity of biospecimens being used in cancer research and the diversity of collection pathways through which these are obtained has changed significantly. This observation is important for biobanks given that the cost to support the supply of biospecimens with complex extrinsic as opposed to simple intrinsic quality characteristics is greater. For biobanks to manage sustainability, optimize utilization, and meet changing research demand, they may need to adjust their operational models to better support the supply of these types of biospecimens.

Opportunities and Risks for Research Biobanks in the COVID-19 Era and Beyond

The SARS-CoV-2 pandemic, which caused a global outbreak of COVID-19 disease, has been a crisis of extraordinary proportions, causing serious impacts for research and public health. Biobanks have played a key important role in understanding the disease and response. In our article we will highlight the opportunities and risks of biobanks during and after the pandemic. The different aspects of safety and sustainability have and will be the main challenges for biobanks. Furthermore, the role of biobanks in biomedical research and public health has been emphasized as well as opportunities that have arisen for their participation in research.

The Utilization of Biospecimens: Impact of the Choice of Biobanking Model

The term research "biobank" is one of multiple names (e.g., bioresource, biorepository,) used to designate an entity that receives, collects, processes, stores, and/or distributes biospecimens or other biospecimen-related products (e.g., data) to support research. There are multiple organizational models of biobanking used by bioresources, but the primary goal of all bioresources should not be simply to collect biospecimens, but ultimately to distribute almost all collected biospecimens and/or data to support scientific research; bioresources should serve as "biodistributors" rather than "biovaults." The appropriate choice of model is the first step in ensuring optimal biospecimen utilization by a bioresource. This article discusses some of the different models that may be used alone or in combination by a bioresource providing biospecimens for research; it describes the factors affecting the choice of the most appropriate model or models, the advantages and disadvantages of the various models, and a discussion of the impact of the choice of the model on biospecimen utilization. Frequently, problems with biospecimen utilization are not caused by any single model, but rather a mismatch between the choice of model and goals of the bioresource, and/or problems with the subsequent design, goals, operations, and management of the bioresource after a model is selected.

Ensuring Effective Utilization of Biospecimens: Design, Marketing, and Other Important Approaches

A number of studies have shown that underutilization of biospecimens from bioresources (biobanks and biorepositories) is a significant concern. In addition, biospecimen underutilization has been identified as an ethical as well as practical concern. The utilization of biospecimens is affected by many factors, including the establishment of a scientific need for the biospecimens, the design of the bioresource, strategic planning, biospecimen quality and fitness for purpose, informed consent considerations, access policies and procedures, and marketing. This article discusses the impact of these factors on biospecimen utilization and provides suggestions for how bioresources can optimize biospecimen utilization from their collections.

Commentary on Improving Biospecimen Utilization by Classic Biobanks: Identifying Past and Minimizing Future Mistakes

Many classic biobanks collect more human tissues than they distribute, leading to increased inventories, unnecessary storage, increased expenses, and reduced chargeback income. This situation is a result of biobanks operating without well-defined goals, having incorrect views of the potential number of investigators who will utilize specimens, and collection of biospecimens without adequately considering the need for specific tissues by investigators. These deficiencies frequently lead to unrealistic plans for biospecimen utilization and biobanks that are larger than necessary. For example, tissue collections usually are not periodically compared with biospecimen distribution and modified accordingly. An ethical issue has arisen as to the acceptability of consenting patients for the use of their tissues in research without a realistic planned approach to distribution of the biospecimens and their ultimate utilization in supporting biomedical research. These issues and how to minimize them are discussed in this commentary focused on how classic biobanks can improve utilization of their biospecimens.

Issues in the Use of Human Tissues to Support Precision Medicine

Precision medicine is an approach in which the characteristics of patients as well as their diseases are used to identify optimal therapy; it links researchers, patients, health care providers, and clinical laboratories. In precision medicine, specific molecular characteristics of an untreatable cancer can be targeted by specific molecular-based therapy. Access to high-quality human tissues is necessary to determine many characteristics of patients and their diseases (such as targetable molecules). There are ethical issues in using human tissues in precision medicine, including informed consent and confidentiality, optimal utilization, quality of tissues, and minimization of bias. When human tissues are obtained for patient therapy, the bioresource should be a component certified by Clinical Laboratory Improvement Amendments. For precision medicine to benefit medically underserved populations requires extensive focused research, planning, and resources, some of which are currently unavailable at rural and other sites where care is provided to underserved populations.