As a model for living tissue in the human body, fresh human tissue is our best solution. For oncology researchers, fresh tissue provides a platform for early-stage immunotherapy development. In addition, individual tumor cells (either primary or dissociated) provide the ability to characterize the tumors and explore important cellular and molecular pathways.Additionally, patient-derived xenografts offer a platform for basic cancer research and preclinical therapeutic evaluations. For a variety of diseases, fresh tissue plays a key role in primary cell functional assays, cell line development, or biomarker and gene expression assay development. In each of the stated assays, the goal is to gather new data from tissue or cells that are in as lifelike a state as possible.
If you have already decided to use fresh human tissue for your research, what further details should be considered as you work to obtain the fresh tissues you need?
The Choice Between Living Subject or Deceased Donor Tissues
When obtaining specimens from living subjects, the ability to acquire tissue relies on standard of care (i.e. where tissue resection occurs as part of the therapeutic treatment for the patient). This tissue, surgically resected, removed from the operating room, and reviewed by pathology, is placed into ice-cold media quickly, usually within 60 minutes of resection. This brief warm ischemic time prior to submersion in media makes fresh surgical tissue the best choice for researchers whenever possible. Typically, oncology and some auto-immune tissues are candidates for resection and may be available from surgical collection partners.
However, not all tissues of interest are surgically resected. Where tissue requirements cannot be met from surgical specimens, samples may be collected from deceased donors. For abdominal and thoracic organs or tissue samples, the freshest tissues can be obtained from shared organ donors. These are donors who may have been able to donate some but not all of their internal organs for transplant. Or, these donors may have initially appeared to be organ donor candidates but were unfortunately ruled out for one reason or another. From these donors, the samples collected typically have less than 12 hours of ischemia time prior to resection and placement in ice-cold media.For all other organs and tissue types, researchers usually inquire about samples from post-mortem donors who were not candidates for transplant. Typically, these samples can be collected and placed in media within 24 hours of death. These post-mortem donors are good sources for normal controls. Diseased samples of a particular diagnosis may also be available, but clinical treatment information may not be specific enough for particular research goals.
Fresh Whole Blood
In some cases, research may require fresh whole blood to identify biomarkers, circulating tumor cells, or other metabolites of interest. Blood products may be collected from subjects during outpatient visits and prior to surgeries. Bloods may also be collected from shared organ donors and post-mortem cases, although generally only as companion samples to the tissues collected. If whole blood is the primary matrix of interest, researchers typically choose to request blood-only cases. In these instances, BioIVT can target the widest group of subjects for the quickest collections.
Considerations for Experimental Design
For oncology researchers, it is essential to consider the types of cases where surgery is medically recommended. For instance, prostate tumor is not always resected, and when it is, it is typically removed in very small pieces with uncertain tumor content. Similarly, current medical practice does not support the resection of small cell lung cancer (SCLC). Thus, samples are only available via archival FFPE biopsy remnants or occasionally in fresh frozen or FFPE block in the rare event that SCLC is resected in error. A variety of types of late-stage cancers are typically deemed inoperable and are therefore almost never available for collection. Generally, keeping weight requirements as low as possible and keeping any screening criteria focused on only the two or three elements that are truly essential to experimental design yields the most efficient collection to support research needs.
A second key point for surgical oncology collections involves pathology staging. Although a case may be clinically staged prior to surgery, this stage information usually does not match the pathological staging results. Because pathology staging cannot be completed until the final path review is done, usually several days after surgery, a definitive screen for fresh tissue collections based on tumor stage is not possible prior to receipt. Alternative screening methods include estimating the stage range based on type of treatment prior to surgery. If a donor screen is based on prior treatment, its preferable to select for treatment by drug class rather than by specific agent, i.e., screening for subjects who had received platinum-based chemotherapies, or immunotherapies prior to resection for example.
Transit and Packaging of the Tissue
With over ten years of experience in fresh tissue collection and shipping, the BioIVT delivery logistics and fresh tissue packaging processes have been tested and honed extensively. Surgical tissues are collected into ice-cold DMEM, with an antibiotic cocktail added when appropriate. However, tissue can be collected into any media of preference. BioIVT standard fresh tissue packaging maintains a temperature of 2-7ºC for up to 72 hours. Internal testing has shown that cells can remain viable using our media and packaging method for up to 5 days after surgery. Though our packaging maintains tissue quality for several days, our delivery systems allow for tissue to be consistently delivered within 24 hours of resection for US clients (excluding Hawaii, Alaska, and the Territories). For most European clients, our delivery timeframe ranges between 24-36 hours from surgery, and typically clients can expect to receive fresh surgical tissue the next business day after resection.
Learn more about BioIVT’s team of experts who specialize in fresh tissue collections. To inquire about our capabilities or to discuss your challenges related to fresh tissue needs, reach out to our team.