Days Set Up
Monday - Friday
Analytic Time

18 - 23 days

Soft Order Code

Test Updated:


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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

Visit our provider FAQ and learn about common questions to ordering tests.

Test Overview

Test Methodology

CD4 cell culture assay for phenotypic recombinant-virus co-receptor tropism.

Test Usage

Phenotypic determination of the type of co-receptor (CCR5, CXCR4, or both) used by the patient's HIV-1 strain to enter host CD4+ cells (HIV-1 entry co-receptor tropism).

Reference Range

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Onsite

Collect specimen in a lavender top or PPT (pearl top) tube. Deliver to Specimen Processing immediately. Must be spun and frozen within 2 hours.

Collection Offsite

Collect specimen in a lavender top or PPT (pearl top) tube. Centrifuge, aliquot plasma into a plastic vial within 2 hours of collection and freeze.

Normal Volume
3 mL EDTA plasma
Minimum Volume
1 mL EDTA plasma

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.