About the Lab

The laboratory of Nikki Posnack, Ph.D., investigates the impact of environmental and clinical perturbations that can impact cardiovascular function. Recently, our team has focused on biocompatibility concerns surrounding inadvertent plastic chemical exposure from medical devices – including blood storage bags and cardiopulmonary bypass/ECMO circuits. Other projects in the lab are focused on red blood cell storage lesion and its role in cardiac complications and developing a 3D tissue model (from live human cardiac tissue) to study age-dependent effects of pharmacotherapies. Accordingly, my team has extensive expertise using a multitude of cardiovascular models, including intact heart and cellular preparations for electrophysiology, dual optical mapping of calcium/voltage, and contractility measurements. The latter also includes the use of large animal models for optocardiography studies, which are performed by only a handful of research groups.

Does biocompatibility contribute to transfusion-related adverse effects?

Nearly 15 million transfusions are performed in the United States each year. Despite the frequency, transfusion procedures are not without risk. Blood transfusion complications may be attributed to heavy exposure to plastic devices, which are fabricated with chemicals that exert endocrine-disrupting properties. Our laboratory is investigating whether medical device biocompatibility and chemical exposures are underlying contributors to cardiovascular and autonomic dysfunction. We are also investigating alternative materials to identify safer biomaterials, chemicals and/or surface coatings for transfusion devices and blood banking.

Assessing Pediatric Cardiac Safety, Toxicity and Therapeutic Targets

Pediatric cardiac research can be stalled by a shortage of appropriate models. Despite differences in neonatal, pediatric and adult hearts, our current knowledge is largely limited to adult heart physiology. Unfortunately, current pharmacological agents have been developed with the adult population in mind and can target mechanisms that are only found in the mature myocardium. A more representative model is needed to drive pediatric cardiovascular research. Our laboratory is working to establish clinically-relevant models to monitor developmental changes in cardiac electrical activity and mechanical function. We are also working to translate these findings to humans.

Red Blood Cell Lesion and the Impact on Cardiac Electrophysiology

Red blood cell (RBC) transfusions are a life-saving treatment for many critically ill children and adults; however, a series of biochemical, functional and metabolic changes are known to occur to preserved RBCs as they are stored over time. These changes are commonly referred to as red blood cell “storage lesion.” Several clinical studies have suggested that RBC storage lesions can contribute to adverse cardiac events and influence mortality and morbidity outcomes. Our laboratory is investigating the changes that occur to stored RBCs over time (prior to patient blood transfusion) and how these changes can interfere with normal cardiac electrical activity.