Changes in Peripheral Blood Over a Person's Lifetime

Posted by Luke Doiron on Aug 25, 2016 8:00:00 AM



Investigating the composition of peripheral blood of an individual can provide a window for both innate and outside experiences. While genetics will certainly influence composition, experiences like stress, disease, smoking and infection will also have an impact. Researchers studying cells isolated from peripheral blood donors need to be aware of the diverse influences that can affect their baseline. Some examples of these are outlined below.

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How to Measure Expression in Tissue Microarray Samples

Posted by Luke Doiron on Aug 23, 2016 8:00:00 AM


Tissue microarray technology is powerful. The technology yields gene expression profiles that are a window to tumor biology, oncology, and diagnostic test development (Shi et al, 2013). A microarray is defined as a supporting material onto which molecules or fragments of DNA or protein are attached in a regular pattern for use in biochemical or genetic analysis. Tissue microarrays (TMAs or tissue chips) are constructed of paraffin blocks comprising (up to 1,000) numerous discrete tissue cores assembled in array fashion for analysis by immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and mRNA in situ hybridization.

The genesis of the tissue microarray (TMA) technology two decades ago was the discovery by Battifora et al in 1986 of how 1 mm thick rods of different tissues could be wrapped in a sausage-like sheet of small intestine and embedded in paraffin to form a multitumor tissue block (MTTB). The technique was refined as an array in 1987, and although simultaneous assessment of many tissue specimens at the same time under the same conditions was now feasible, the inability to pinpoint the nature of each tissue specimen remained problematical. By 1998, Kononen et al had further refined TMA to permit rapid construction of microarrays and commercialization of the TMA device. The popularity of the TMA device continues to increase with commercial marketing, first by Beecher Instruments, and currently by Estigen Tissue Science.

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The Role of T Cells in Peripheral Blood Mononuclear Cells

Posted by Luke Doiron on Aug 18, 2016 8:00:00 AM


Peripheral blood mononuclear cells (PBMCs) are isolated from other cells types in human blood, most often by gradient centrifugation using Ficoll. Lymphocytes in the PBMC layer include T-cells, B-cells and NK-cells. Using certain immunological markers to identify the various populations of cells helps researchers determine the role of each cell type in the body’s disease defense system. T-cells are commonly separated into CD4+ (also know as helper T-cells) and CD8+ cells, which are cytotoxic. Further characterization of the roles of these important immune defense cells is currently a large area of investigation for researchers in a variety of different disease fields.

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Prostate Cancer: Wait It Out, or Treat It Quickly?

Posted by Quinton Stevens on Aug 13, 2016 12:00:00 PM



Prostate cancer is one of the single most common manifestations of cancer in the world today. Approximately 1 in 6 men will be diagnosed with prostate cancer over the course of their lifetime. If given time and poor circumstance, it can be a fatal disease that can damage tissue all across the body, leading many to act quickly to have it treated and removed.

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New Developments in Extracting Protein from FFPE Tissue

Posted by Luke Doiron on Aug 9, 2016 8:00:00 AM


Formalin-fixed, paraffin-embedded (FFPE) biospecimens offer a robust and abundant resource for biomedical research. With the increased need for specimens that permit molecular analysis of tumor tissues and isolation of the proteins in them to develop more effective cancer therapies, researchers need a process that enables safe, efficient, reproducible and cost-effective deparaffinization.

We previously wrote about a method that used xylene to extract a variety of full-length proteins from FFPE biospecimens. The process takes about two and a half hours; however, it may create less than optimal conditions for extraction of other proteins and potentially exposes lab technicians to a hazardous organic solvent. Other methods that do not use xylene require multiple snap-freeze steps using ethanol on dry ice as well as boiling and centrifugation, processes that are time consuming and may not work with all proteins.

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Isolation of Circulating Tumor Cells from Human Cancers

Posted by Luke Doiron on Aug 9, 2016 8:00:00 AM


Personalized medicine for the treatment of human cancer has been said to encompass multiple dimensions (Burke et al, 2015). The scope includes not only genomics analysis of tissue but also testing of blood. One of the fastest moving trends in genomics testing is the liquid biopsy, which is the sampling and analysis of non-solid biological tissue, primarily blood, serum, and plasma. Circulating tumor cells (CTC) in vitro diagnostic assays in blood are among the several types of liquid biopsy technologies at various stages of development, use, and marketing; another type of liquid biopsy is the cell-free DNA (cfDNA) assay.

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Biospecimen Pre-Clinical Variability Studies to be Funded by the NCI

Posted by Luke Doiron on Aug 4, 2016 9:29:45 AM


“And everything under the sun is in tune, but the sun is eclipsed by the moon,” are lyrics from the famous Pink Floyd album, Dark Side of the Moon. The great promise of precision medicine, biomarker science, and biospecimen testing is attenuated by pre‑analytical variability, which has been said to be the “dark side of the moon,” in laboratory testing (Lippi et al, 2006).

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FFPE Block Application: Early Detection of Pancreatic Cancer

Posted by Luke Doiron on Aug 2, 2016 8:30:00 AM


Pancreatic cancer is typically not diagnosed until the patient seeks medical treatment after having experienced symptoms including abdominal pain, weight loss, itching, and jaundice for weeks or months. At this point, diagnosis is relatively straightforward using imaging and biopsy techniques, but a cure is unlikely as the cancer is already quite advanced. Identifying early markers of pancreatic cancer is a priority for oncology researchers as early detection of the disease is critical to improving patient survival rates.

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