Fig 2. Viral enhancement of p-i acting drugs
Drugs bind to proteins (non-covalently, reversibly, low affinity), including immune receptor proteins. Such low-affinity binding is mostly clinically irrelevant, as it is insufficient to elicit T cell stimulation. However, during viral infections, immune receptors are expressed in much higher density, the chances for increased low affine interactions increases and the p-i binding may become functionally relevant. T cells are activated by the drug, as long as the virus-induced immune stimulation lasts. When the virus-induced immune activation is over, the patient no longer shows any drug reactivity.