The new Cyto-Chex BCT is an FDA-cleared blood-collection tube that preserves the integrity of white blood cells and their surface epitopes for up to 7 days. The stabilization of these cell markers for up to 7 days extends the options for transport and storage of patient specimens that require immunophenotyping of white blood cells by flow cytometry.
     Immunophenotypic markers (CD3, CD4, CD8, CD16/56, CD19, CD45, and others) are critical to the diagnosis and management of a wide range of immune system disorders. CD4+lymphocyte count by flow cytometry, in particular, is the current gold standard for monitoring HIV/AIDS antiretroviral treatment. Patient specimens collected into conventional tubes, however, must often spend time in batching or shipping that can exceed the integrity interval for flow cytometric analysis. This can result in costly and time-consuming redraws that cause delay and interfere with optimal delivery of care.
     Collection of normal donor and HIV-infected donor peripheral blood into the novel Cyto-Chex BCT has shown that antigen epitopes are preserved for at least 7 days without compromising the ability to differentiate the white blood cell populations. This 7-day stability allows samples to be drawn on any day of the week for analysis, even when further storage and shipping are involved.
     The Cyto-Chex BCT is a standard 13 x 75 mm vacuum-assisted tube configured for a 5 mL draw, and includes 60 microliters of concentrated reagent with a cell preservative and anticoagulant. While stabilizing whole blood samples at room temperature to accommodate transportation and work flow requirement, the small volume of reagent permits direct flow cytometric analysis without the need for dilution corrections. Unused tubes may be stored for 1 year at room temperature.

Streck Laboratories
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