47
EVENT FORMAT
Lecture
2020
Januar y
12-2 3
Delivering Proteins in Hot and Hostile Places
Transportation of vaccines requires constant refrigeration from the time they are formulated until they are
administered. The infrastructure to keep these medicines cold contributes to 80% of their total cost. Approaches
to create temperature stabilized protein formulations typically involve confining proteins in a polymeric or excipient
matrix. It has long been appreciated that proteins immobilized in environments that limit their conformational freedom
to enhance their thermal stability by inhibiting the folding pathways to lower energy denatured states.
We recently described a method to produce protein-stabilizing shells over virus-like particles (VLPs) using a porous
metal-coordination polymer comprised only of Zn2+ and 2-methylimidazole (HMIM) called a zeolitic imidazolate
framework (ZIF). This composite nanomaterial (VLP@ZIF) can be subjected to conditions (extreme heat and prolong
exposure to organic solvents) that should denature the VLP; however, after dissolving the ZIF shell in the presence
of chelators the released VLP still binds antibodies as well as unstressed samples. Live mouse imaging experiments
show that VLP@ZIF injected subcutaneously slowly dissolves over the course of 10 days and the mice produce a
much more powerful antibody response from the “VLP@ZIF” composite compared to the unencapsulated VLP. We
can exploit the protective effects of the ZIF shell to create extended release polymer formulations that would
eliminate the need for multiple booster shots. Presently, however, the mechanism of in vivo release and how the
ZIF-based nanocomposites interact with the immune system are open questions.
SPEAKER Jeremiah Gassensmith
CREDITS 1
Associate Professor of Chemistry and Biochemistry at the University of Texas at
Dallas
DESCRIPTION