CD40LG and Autoimmunity: While anti-CD40L showed promise in murine models of inflammatory conditions, notable past clinical trials involving anti-CD40L Ab therapies for autoimmune disorders have encountered thromboembolic complications stemming from platelet activation in response to the Fc domain on anti-CD40L drugs (Boumpas et al., 2003; Kawai et al., 2000; Langer et al., 2005).