Open Forum Information: Sunday, June 22
8:30 am – 5:00 pm
BIOTEC Open Forum: Protein Aggregation – Therapeutic and Pharmaceutical Viewpoints
An additional fee is required to attend this open forum.
Protein Aggregation in Human Diseases
Over several decades, clinicians have been struggling to deal with the formation of insoluble protein aggregates in particular diseases. Intra-/extra-cellular protein misfolding/aggregation are features of many late-onset neurodegenerative diseases, called proteinopathies or conformational disorders. These include Alzheimer's disease (β-amyloid), Parkinson's disease (α-synuclein), Amyotrophic Lateral Sclerosis (ALS, mutant SOD1), tauopathies (AD, Nieman Pick disease), and polyglutamine expansion diseases [e.g., Huntington's disease; and various spinocerebellar ataxias [SCAs], like SCA3]. There are no effective strategies to slow or prevent the neurodegeneration resulting from these diseases in humans. The mutations causing many proteinopathies confer novel toxic functions on the specific protein, and disease severity frequently correlates with the expression levels of the protein. In most of the diseases mentioned above, improper folding of proteins is an early event in pathogenesis. Possible causes that have been postulated are exposed hydrophobic domains, reduced intracellular disulfide bonds and loss of metal ions such as Cu, Zn, etc. At symptomatic stage, large aggregates that are localized in the cytoplasm/nucleus/mitochondria/ER are evident. The role of these microscopically visible inclusions are yet unclear, whether they are pathogenic or protective [by sequesteration of disease-causing protein]. However, several lines of evidence suggest that the small, soluble precursors - protofibrils (oligomers) seen in the initial stages of aggregate formation may actually be the toxic species. Several endogenous mechanisms may be at play in vivo in facilitating large aggregate formation, but it is conceivable that the initial stages of multimerization resulting in soluble oligomers may be prevented by chemical means. Therapeutic strategies need to be aimed toward preventing misfolding and protofibril formation of disease-causing proteins in vivo.
Protein Aggregation in Biologics Formulations
The current view of the mechanism of aggregation involves the self-association of “intermediate” or “transient” states along the folding pathway. Aggregation in biological products can be induced by stress conditions such as heating or shear through substantial perturbation of the native state. However, the aggregation that occurs under nominally mild solution conditions that the formulation provides for the biologic, is more critical to the determination of shelf-life of the product and any consequent risk for immunogenicity that arises. The mechanistic details of protein aggregation in native-like conditions remain poorly understood, although strategies have been developed to create “kinetically” stable formulations. The objective of this open forum will be to extract synergies from these two fields of inquiry which have a lot in common but approach the question of aggregation from different perspectives.
Moderators
Jeyanthi Ramasubbu, Ph.D.
ALS Therapy Development Institute
Satish Singh, Ph.D.
Pfizer Inc.
8:30am - 9:15am
Protein Misfolding in Disease
Arthur Horwich, Ph.D.
Yale University School of Medicine
9:15am - 10:00am
Use of Fluorescent Probes to Detect Protein Structural Variants and Aggregates
Wim Jiskoot, Ph.D.
Leiden University
10:00am - 10:25am
Coffee break
10:25am - 11:10am
Detecting Protein Misfolding In Vivo: Application to Lou Gehrig's Disease and Prion Disease
Avijit Chakrabartty, Ph.D.
University of Toronto
11:10am - 12:00pm
Interactive Discussion
12:00pm - 1:00pm
Lunch
1:00pm - 1:45pm
Lens Crystalling Aggregation and the Formulation of Lens Cataracts
Jonathan King, Ph.D.
California Institute of Technology
1:45pm - 2:30pm
Revisiting the Mechanistic and Quantitative Roles of Conformational Change and (non)native Interactions in Protein Aggregation Kinetics
Christopher Roberts, Ph.D.
University of Delaware
2:30pm - 2:55pm
Coffee break
2:55pm - 3:40pm
Inhibition of Alpha-Synuclein Aggregation in Parkinson’s Disease: Role of Molecular Chaperones and Protein Repair
Jean-Cbristophe Rochet,.Ph.D.
Purdue University
3:40pm - 5:00pm
Interactive Discussion and Closing Comments
Some Questions:
- What can we learn from aggregation encountered in formulation development of protein biopharmaceuticals in terms of understanding aggregation in disease states?
- How can tools and techniques developed to understand disease states be applied to the study of aggregation in biopharmaceuticals and how can the knowledge be applied to design better formulations or improve the molecule itself?
- Can any of the strategies developed to prevent aggregation in biopharmaceuticals be applied to inhibition of protofibril formation by disease-causing proteins?
- Can current understanding translate into prevention or therapy for biopharmaceuticals and proteinopathies respectively?
- What do we know about the various processes that produce these aggregates in pharmaceuticals and in diseases? Are there any similarities in the nucleation events?