Currently, the standard tests for Lyme Disease measure antibody production after exposure to a bacteria, Borrelia burgdorferi. Often, the tests are performed too soon after infection, before antibodies can be produced. Also, infected patients experiencing immune suppression may not have detectable levels of the antibodies to the antigen. In both cases, test results are often false negative.

A new test for Lyme Disease has been developed, ISPOT Lyme by Pharma Labs, which focuses on T-cell activity instead of antibody production. Modeled after the ELISPOT test for TB, it measures interferon gamma (IFN-γ) secreted by T cells in response to stimulation by the B. burgdorferi antigen proteins -- DbpA, OspC, p100, and VlsE-1. After isolating and culturing lymphocytes from a patient's blood sample, they expose the cultured lymphocytes to the B. burgdorferi antigens. If the lymphocytes 'recognize' the antigen, due to previous exposure, they secrete IFN-y which reacts with a blue-colored dye visible in the culture.

Question: Can T-Cell exhaustion affect the usefulness of a serological assay which measures T-cell sensitivity to specific antigens?

  • $\begingroup$ It is called ISPOT for Lyme Disease, Pharmasan Labs. Unfortunately, the only acess I have to information about the test is promotional literature. However, it is fast being touted among patients in the Lyme community as THE answer to diagnostic testing because it focuses on T cell sensitivity instead of antibody production. $\endgroup$ – Stephanie May 4 '16 at 23:28
  • $\begingroup$ If at all still interested: The iSpot Lyme test uses the ELISPOT technique to count B. burgdorferi-sensitized T cells by capturing IFN-γ secreted by these T cells. More specifically, when IFN-γ is released a spot of insoluble precipitate is formed at the site of the reaction. Evaluating the number of spot forming units (SFUs) provides a measurement of B. burgdorferi sensitive effector/memory T cells in the peripheral blood. The SFU count correlates to a patients T cell reaction to B. burgdorferi. That's all I've got. $\endgroup$ – Stephanie May 4 '16 at 23:36

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