Trial Information

On one hand we want to perform a detailed analysis of the T-cells generated in thymomas in
terms of their functional capacity and their specificity. We will analyse blood and thymoma
tissue of patients with myasthenia gravis with thymona, patients with myasthenia gravis
without thymona, and patients with thymona without myasthenia gravis.

Hypothesis: The T-cells which are generated in the thymoma in thymoma-associated myasthenia
gravis can be differentiated from T-cells which are generated in normal thymoma tissue with
regard to functionality and T-cell receptor specificity. This non-physiological T-cell
maturation might be the cause for the formation of auto-antibodies.

On the other hand we want to examine the effects of thymectomy on the immune system in the
context of myasthenia gravis. We will analyse blood and thymoma tissue of patients with
myasthenia gravis with thymona, patients with myasthenia gravis without thymona, patients
with thymona without myasthenia gravis and patients with cardiac, or thyroid surgery.

Hypothesis:

1. Thymectomy in patients with myasthenia gravis leads to a reduced number of
auto-reactive, e.g. Acetylcholine receptor (ACh-R)-specific T cells. In contrast,
T-cells with other specifities, for example against CMV or tetanus, are not affected.

2. The non-physiological export of thymocytes from thymomas leads to a significant shift
in leukocyte populations in peripheral blood.