Development of a new vaccine technology using the carrier/adjuvant properties of ASC specks

Abstract

Pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) are sensed by the nucleotide-binding oligomerization domainlike receptor (NLR) family of proteins in the cytosol for the regulation of innate immunity responses. Certain NLRs such as NLRP3 induce the formation of in ammasome complexes. Caspase-1 is activated within the in ammasome multiprotein complex via interaction with apoptosis-associated speck-like protein (ASC). The adaptor molecule apoptosis-associated speck-like protein containing a CARD (ASC) is 22 kDa cytosolic protein that contains a C-terminal caspase recruitment domain (CARD) and an Nterminal pyrin (PYD) domain. Upon stimulation, ASC combines into laments and with many ASC molecules to form a globular structure called ASC speck. These specks can exist inside the cell or can be released to the extracellular space in order to amplify the signals such as many cytokines. In previous data of our group, arti cial loading of ASC specks was shown. We showed that ASC specks in PBS remained stable at 37 C for 30 days. We have also shown the long-lasting stability of ASC specks inside the spleen of mice. The aim of the thesis is to purify ASC specks with antigen epitopes and achieve vaccination using ASC specks. After stimulation of THP-1 macrophages with puri ed ASC specks, we showed an increase in the secretion of certain in ammatory cytokines such as IL-1beta and TNF-alpha. Besides, tH5-ASC immunized C57BL/6 mice had higher anti-H5 IgG levels compared to other groups of immunized mice. Lastly, we showed that i.p. injected tOVA-ASC specks may go to the EG7-OVA thymoma tumor in C57BL/6 mice and cause complete eradication or reduction in tumor size.