ITT Cytokine Testing: Diagnosing Lyme Disease (and Beyond)

Posted on November 17, 2010 by Sirid Kellermann, Ph.D.

Our colleagues at Pharmasan Labs, Inc. recently were the recipients of a grant under the highly competitive Qualifying Therapeutic Discovery Project (QDTP) Program.  The grant was awarded for the company’s novel ITT®/cytokine immune testing platform, developed in close collaboration with our NeuroScience R&D group (you can learn more about the grant in our press release).

This novel test platform, combining the immune tolerance test (ITT) with an assessment of antigen-stimulated cytokines, has the potential to advance the diagnosis of a spectrum of immunological challenges, allowing practitioners to provide more targeted therapeutic interventions.

Take, for example, Lyme disease, which is caused by infection by various genospecies of Borrelia, a tick-borne bacteria. Historically, the diagnosis of Lyme disease has relied chiefly on testing for antibodies to Borrelia. However, these serological Lyme tests are bedeviled by low sensitivity (false negatives), an issue we recently reviewed in a white paper, Novel Laboratory Assessments for the Detection of Borrelia burgdorferi. This can lead to a misdiagnosis, and the potential for a chronic Borrelia infection that can increase the risk of system-wide organ damage.

To address the need for better Lyme diagnosis, we developed MY Lyme Immune I.D.TM. Here’s how the test works. An individual sends a blood specimen to the laboratory, where white blood (immune) cells are isolated. In the ITT portion of the test, the cells are cultured for five days with individual B. burgdorferi-specific antigens, such as VlsE-1 and other proteins. If T cells that respond to a particular antigen are present in the culture, they become activated and proliferate. This indicates that the person has been exposed to B. burgdorferi.

It’s important to note that the ITT by itself cannot distinguish between an immune response that is currently in progress, and one that happened in the past. That’s because it cannot tell the difference between so-called “effector” T cells that are currently fighting an active infection, and “memory” T cells that responded years ago to a prior infection and continue to circulate in the bloodstream. Knowing whether the infection is active is key to determining what type of treatment regimen, if any, is warranted.

That’s where this novel platform stands apart from other currently available cell-based assays: the cytokine assessment helps detect an active immune response. The lab sets up a second culture of white blood cells in the same way as for the ITT , but the incubation is only 24 hours. In this short time frame, increased cytokine production compared to control cultures would only occur if the donor’s blood contains effector T cells that are actively engaged in an immune response against Borrelia.

In this manner, the cell count (ITT) tells us whether that individual has been exposed to a given antigen, and the cytokine profile serves as a biomarker of an ongoing immune response.  (In a future post, we’ll expand our discussion of the utility of biomarkers in assessing perturbations in the NEI Supersystem©.)

Of course, the beauty of the ITT/cytokine platform is that it can be set up to test virtually any antigen, including those derived from infectious organisms, foods, and environmental antigens like molds, greatly facilitating root cause analysis in chronically ill patients.

http://neuroendoimmune.wordpress.com/2010/11/17/ittcytokine-testing-diagnosing-lyme-disease-and-beyond/