Figure 2.

The activation of a T-cell by the presentation of an antigen (red sphere) by th Major Histocompatibility Complex (MHC) I and beta-microglobulin to the T cell receptor (TCR) promotes interferon gama release and stimulation in the tumor through interferon-gamma recetor 2 of PD-L1 through the JAK-STAT signaling pathway and its transcription factor (Interferon-responsive factor 1 (IRF-1). This diagram also illustrates why JAK and beta2 microglobulin are potential biomarkers of immune checkpoint response.