Immunoenzymatic Assays to Target Central and Peripheral Inflammatory Markers in Preclinical and Clinical Studies of Hepatic Encephalopathy

Inflammation has emerged as an important mechanism in the pathophysiology of cognitive and motor impairment related to hepatic encephalopathy (HE). Systemic inflammatory response syndrome (SIRS) associated with liver disease is common among patients with acute liver failure (ALF), leading to high mortality risk and the development of HE. Peripheral proinflammatory mediators cross the blood-brain barrier, leading to the activation of astrocytes and microglia, oxidative stress, and changes in neurotransmitter levels. Translational investigation of the inflammatory mechanisms underlying experimental HE represents a promising way for the elucidation of the pathophysiology of human HE, as well as the development of potential biomarkers and novel therapeutic targets. HE-related cognitive dysfunction is associated with worse employment, income, and caregiver burden, impacting family functioning and medical adherence. The development of potential biomarkers for HE screening, diagnosis, prognosis, and prediction/monitoring clinical response to an intervention can bring benefits to patient care, clinical research, and therapeutic development. Immunoenzymatic assays, especially ELISA, but also immunoblotting and immunohistochemistry are among the most employed methods to detect or measure these molecular biomarkers. In the current chapter, we will provide an overview of these immunoenzymatic techniques covering aspects ranging from sample collection in experimental models and humans to methodological procedures and potential pitfalls.