616 - Neutrophil-Avid Nanocarriers as a Potential Therapeutic for Autosomal Dominant Hyper Ig-E Syndrome (AD-HIES) STAT3 Deficiency Patients

Poster Number: 616
Publication Number: 616.200

Kathryn Rubey, Children's Hospital of Philadelphia, Philadelphia, PA, United States; Andrew J. Paris, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States; Alexander Mukhitov, Perelman School of Medicine at the University of Pennsylvania, Narberth, PA, United States; Susan Lin, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States; Jacob W. Myerson, University of Pennsylvania, Philadelphia, PA, United States; Jacob Brenner, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States; G. Scott Worthen, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Vera Krymskaya, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States; Jennifer Heimall, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States

Background: Autosomal Dominant Hyper-IgE Syndrome (AD-HIES) STAT3 Deficiency (Job Syndrome) is a rare inborn error of immunity which is associated with severe infections of the skin and lungs, predominantly due to Staphylococcal and fungal pathogens. These infections are associated with bronchiectasis and pneumatocele formation. Invasive Aspergillus infections are a common cause of premature death in patient with AD-HIES STAT3 Deficiency. We have recently shown (Nature Nanotechnology in press) that our lab’s group of Neutrophil-Avid Nanocarriers (NANs) are phagocytosed by murine neutrophils, that interaction is enhanced when the particles are opsonized by serum, and they are concentrated within inflamed lungs. NANs are a potential future therapeutic that could improve pneumonia treatment for this patient population.

Objective: We hypothesize that human neutrophils will phagocytose NANs in a complement-dependent manner similar to that seen in our previous mouse studies.

Design/Methods: Blood was obtained from patients with AD-HIES STAT3 Deficiency via IRB approved protocol. Neutrophils were isolated by density gradient followed by negative selection. For opsonization, green fluorescent NANs were incubated for 1 hour with patient serum, and then washed. Neutrophils were then incubated with either naïve or opsonized NANs. The amount of NAN-neutrophil interaction was then quantified by flow cytometry. Confocal microscopy was used to analyze particle location following neutrophil interaction.

Results: As compared to healthy human control neutrophils, STAT3 deficient neutrophils are similarly able to phagocytose naïve NANs. The neutrophil-NAN interaction is enhanced by serum opsonization of particles in STAT3 deficient samples, though the Mean Fluorescence Index measured is less than that seen for healthy control neutrophils. Confocal microscopy confirms that naïve particles seem to bind the neutrophil membrane, while opsonized particles are phagocytosed within the cell.Conclusion(s): These promising results support a potential for the NAN particles to be used as a drug delivery platform in patients with AD-HIES STAT3 Deficiency. Anti-infective nanoparticle preparations, such as Ambisome, are already being used clinically. Our future studies will investigate the ability of NANs to deliver antibiotics to neutrophils in vitro and in vivo, and could potentially lead to further study of clinical applications resulting in improved pneumonia treatment and clearance.