Displaying and delivering viral membrane antigens via WW domain–activated extracellular vesicles

Abstract

Membrane proteins expressed on the surface of enveloped viruses are conformational antigens readily recognized by B cells of the immune system. An effective vaccine would require the synthesis and delivery of these native conformational antigens in lipid membranes that preserve specific epitope structures. We have created an extracellular vesicle–based technology that allows viral membrane antigens to be selectively recruited onto the surface of WW domain–activated extracellular vesicles (WAEVs). Budding of WAEVs requires secretory carrier-associated membrane protein 3, which through its proline-proline-alanine-tyrosine motif interacts with WW domains to recruit fused viral membrane antigens onto WAEVs. Immunization with influenza and HIV viral membrane proteins displayed on WAEVs elicits production of virus-specific neutralizing antibodies and, in the case of influenza antigens, protects mice from the lethal viral infection. WAEVs thus represent a versatile platform for presenting and delivering membrane antigens as vaccines against influenza, HIV, and potentially many other viral pathogens.

Extracellular vesicles as a next-generation therapeutic nanocarrier in disease treatments

“…For example, exosomes can be involved in the delivery of antigenic materials from diseased cells to DCs, which can cross-present the antigen to activate cytotoxic T cells to destroy diseased cells [29]. This concept of utilizing EVs as a cancer vaccine can be dated back to an early study conducted by Zitvogel et al, in which they found that DCs-derived exosomes (DEXs) released from tumor peptide-pulsed DCs can present tumor antigens on the EV membrane to induced cytotoxic T cell activation, leading to tumor suppression [30]. In terms of manufacturing, EVs also remain functionally stable after short-term storage at 4 °C and even thawing from frozen temperatures, along with a retained EV uptake efficiency stable at −20 °C and −80 °C for at least 7 days and 14 days, respectively [23].…”

“…As shown in a recent study, Choi et al utilized an EVs-based technology to selectively present viral surface antigens onto the surface of engineered extracellular vesicles that can be activated by intracellular WW domain to induce antigen-specific immune responses as a means for vaccine development [30]. In this design, a transmembrane fusion protein containing an intracellular WW domain that can react with PPXY motif(s) and viral antigens displayed in the extracellular region is introduced into the EVs surface via the secretory carrier-associated membrane protein 3 (SCAMP3) containing an intracellular PPXY motif found in the EVs.…”

“…Immunization with the engineering EVs fusing with influenza and HIV viral surface proteins was shown to induce the production of virus-specific neutralizing antibodies. In particular, long-term survival was observed in mice models treated with influenza-specific WAVEs, effectively protecting them from the lethal flu virus challenge [30].…”

Optical Imaging of Single Extracellular Vesicles: Recent Progress and Prospects

“…In this review, we will refer to them as EVs and only specify subtypes when they are clearly defined in the corresponding literature.) EV-mediated intercellular communication plays a crucial role in regulating cellular processes such as cell migration, immune response modulation, tissue regeneration, and tumor progression. − For example, EVs derived from immune cells are capable of transporting and presenting antigens, thus enhancing immune responses. − EVs from cancer cells can transport signaling molecules to healthy cells to facilitate cancer metastasis . EVs can also deliver angiogenesis growth factor to promote the formation of new blood vessels, which is important for tissue development and wound healing …”

Rapid and in‐depth proteomic profiling of small extracellular vesicles for ultralow samples

“…Quantitative mass spectrometry (MS)-based proteomics has contributed significantly to our understanding of the molecular composition and functionality of EVs. Proteomic studies have generated a wealth of knowledge in the EV field, providing unprecedented insights into cargo sorting mechanisms [9,10], EV heterogeneity [8,[11][12][13][14], biogenesis [15], surfaceome [16,17], interaction network [18], intracellular trafficking pathways [19], release (including organs [20,21] / tissues [22]), targeting/localization [23], uptake, [24] and function [25,26], to identifying specific marker proteins [27]. Their interrogation of EVs in biofluids has also highlighted their diagnostic potential [28][29][30] and therapeutic targets [31], establishing the role of EVs in health and disease.…”