Session Type: ePosters
Session Title: ePosters
Authors(s): J. Izac (1), D. Varisco (1), E. Harberts (1, 2), J. Duvall (1), R. Ernst (1)
Authors Affiliations(s): (1) University of Maryland - Baltimore, United States, (2) Towson University, United States
Background:
Immunoadjuvants are key components in vaccine formulations that enhance and shape immune responses to vaccines. An ideal broad-based adjuvant should elicit a balanced Th1/Th2 immune response. We previously reported the ability to rapidly generate novel lipid A structures with potent adjuvant capabilities using Bacterial Enzymatic Combinatorial Chemistry (BECC). BECC utilizes expression or deletion of enzymes involved in the lipid A synthesis pathway for Gram-negative bacteria to purify TLR4 without further modifications.
Methods:BECC438b was derived biologically and contains multiple defined lipid A structures. To determine which congener was responsible for adjuvant activity, four synthetic molecules were produced. One similar to the major hexa-acylated species (BECC438s) and three hexa-acylated species designated 16:0/16:0, 14:0/16:0, and 17:0cyclo/16:0. Structural alterations are in the length and position of secondary acyl moieties. Synthetic molecules were tested for induction of NF-κB in immortalized murine and human cells
To determine in vivo efficacy, C57BL/6 mice were vaccinated intramuscularly with each structure and the recombinant Y. pestis F1-V antigen in a prime-boost model. The mice were subsequently challenged to compare the protective efficacy in comparison to PBS and F1-V alone control groups. Additionally, antibody isotyping was carried out to determine if a balanced Th1/Th2 immune response was elicited.
Results:In all cell types, the synthetic molecules showed minimal activation of hTLR4, while BECC438b activated hTLR4, mTLR4, THP-1, and RAW-Blue cell lines, though less than lipid A derived from E. coli, which is highly proinflammatory. In vivo analysis showed that BECC438b produced increased IgG2c titers after both the prime and boost vaccination when compared to Alum, MF59, and PHAD, while also providing a balanced Th1/Th2 response. This response did not vary between male and female mice. The synthetic molecules produced higher IgG2c titers than PHAD, MF59, and Alum. Interestingly, BECC438b produced a significant amount of IgG3 and IgG2b, but not IgE, as comparted to the synthetic versions.
Conclusions:Vaccination with BECC438b or BECC438s provided protection against a lethal Y. pestis challenge, as compared to the other synthetic molecules and increased IgG1 and IgG2c titers. Interestingly, two of the synthetic molecules, 16:0/16:0 and 14:0/16:0, generated increased levels of IgE.
Keyword(s): LPS, Vaccine adjuvant, TLR4 mimeticSession Type: ePosters
Session Title: ePosters
Authors(s): J. Izac (1), D. Varisco (1), E. Harberts (1, 2), J. Duvall (1), R. Ernst (1)
Authors Affiliations(s): (1) University of Maryland - Baltimore, United States, (2) Towson University, United States
Background:
Immunoadjuvants are key components in vaccine formulations that enhance and shape immune responses to vaccines. An ideal broad-based adjuvant should elicit a balanced Th1/Th2 immune response. We previously reported the ability to rapidly generate novel lipid A structures with potent adjuvant capabilities using Bacterial Enzymatic Combinatorial Chemistry (BECC). BECC utilizes expression or deletion of enzymes involved in the lipid A synthesis pathway for Gram-negative bacteria to purify TLR4 without further modifications.
Methods:BECC438b was derived biologically and contains multiple defined lipid A structures. To determine which congener was responsible for adjuvant activity, four synthetic molecules were produced. One similar to the major hexa-acylated species (BECC438s) and three hexa-acylated species designated 16:0/16:0, 14:0/16:0, and 17:0cyclo/16:0. Structural alterations are in the length and position of secondary acyl moieties. Synthetic molecules were tested for induction of NF-κB in immortalized murine and human cells
To determine in vivo efficacy, C57BL/6 mice were vaccinated intramuscularly with each structure and the recombinant Y. pestis F1-V antigen in a prime-boost model. The mice were subsequently challenged to compare the protective efficacy in comparison to PBS and F1-V alone control groups. Additionally, antibody isotyping was carried out to determine if a balanced Th1/Th2 immune response was elicited.
Results:In all cell types, the synthetic molecules showed minimal activation of hTLR4, while BECC438b activated hTLR4, mTLR4, THP-1, and RAW-Blue cell lines, though less than lipid A derived from E. coli, which is highly proinflammatory. In vivo analysis showed that BECC438b produced increased IgG2c titers after both the prime and boost vaccination when compared to Alum, MF59, and PHAD, while also providing a balanced Th1/Th2 response. This response did not vary between male and female mice. The synthetic molecules produced higher IgG2c titers than PHAD, MF59, and Alum. Interestingly, BECC438b produced a significant amount of IgG3 and IgG2b, but not IgE, as comparted to the synthetic versions.
Conclusions:Vaccination with BECC438b or BECC438s provided protection against a lethal Y. pestis challenge, as compared to the other synthetic molecules and increased IgG1 and IgG2c titers. Interestingly, two of the synthetic molecules, 16:0/16:0 and 14:0/16:0, generated increased levels of IgE.
Keyword(s): LPS, Vaccine adjuvant, TLR4 mimetic
Session Type: ePosters
Session Title: ePosters
Authors(s): J. Izac (1), D. Varisco (1), E. Harberts (1, 2), J. Duvall (1), R. Ernst (1)
Authors Affiliations(s): (1) University of Maryland - Baltimore, United States, (2) Towson University, United States
Background:
Immunoadjuvants are key components in vaccine formulations that enhance and shape immune responses to vaccines. An ideal broad-based adjuvant should elicit a balanced Th1/Th2 immune response. We previously reported the ability to rapidly generate novel lipid A structures with potent adjuvant capabilities using Bacterial Enzymatic Combinatorial Chemistry (BECC). BECC utilizes expression or deletion of enzymes involved in the lipid A synthesis pathway for Gram-negative bacteria to purify TLR4 without further modifications.
Methods:BECC438b was derived biologically and contains multiple defined lipid A structures. To determine which congener was responsible for adjuvant activity, four synthetic molecules were produced. One similar to the major hexa-acylated species (BECC438s) and three hexa-acylated species designated 16:0/16:0, 14:0/16:0, and 17:0cyclo/16:0. Structural alterations are in the length and position of secondary acyl moieties. Synthetic molecules were tested for induction of NF-κB in immortalized murine and human cells
To determine in vivo efficacy, C57BL/6 mice were vaccinated intramuscularly with each structure and the recombinant Y. pestis F1-V antigen in a prime-boost model. The mice were subsequently challenged to compare the protective efficacy in comparison to PBS and F1-V alone control groups. Additionally, antibody isotyping was carried out to determine if a balanced Th1/Th2 immune response was elicited.
Results:In all cell types, the synthetic molecules showed minimal activation of hTLR4, while BECC438b activated hTLR4, mTLR4, THP-1, and RAW-Blue cell lines, though less than lipid A derived from E. coli, which is highly proinflammatory. In vivo analysis showed that BECC438b produced increased IgG2c titers after both the prime and boost vaccination when compared to Alum, MF59, and PHAD, while also providing a balanced Th1/Th2 response. This response did not vary between male and female mice. The synthetic molecules produced higher IgG2c titers than PHAD, MF59, and Alum. Interestingly, BECC438b produced a significant amount of IgG3 and IgG2b, but not IgE, as comparted to the synthetic versions.
Conclusions:Vaccination with BECC438b or BECC438s provided protection against a lethal Y. pestis challenge, as compared to the other synthetic molecules and increased IgG1 and IgG2c titers. Interestingly, two of the synthetic molecules, 16:0/16:0 and 14:0/16:0, generated increased levels of IgE.
Keyword(s): LPS, Vaccine adjuvant, TLR4 mimeticSession Type: ePosters
Session Title: ePosters
Authors(s): J. Izac (1), D. Varisco (1), E. Harberts (1, 2), J. Duvall (1), R. Ernst (1)
Authors Affiliations(s): (1) University of Maryland - Baltimore, United States, (2) Towson University, United States
Background:
Immunoadjuvants are key components in vaccine formulations that enhance and shape immune responses to vaccines. An ideal broad-based adjuvant should elicit a balanced Th1/Th2 immune response. We previously reported the ability to rapidly generate novel lipid A structures with potent adjuvant capabilities using Bacterial Enzymatic Combinatorial Chemistry (BECC). BECC utilizes expression or deletion of enzymes involved in the lipid A synthesis pathway for Gram-negative bacteria to purify TLR4 without further modifications.
Methods:BECC438b was derived biologically and contains multiple defined lipid A structures. To determine which congener was responsible for adjuvant activity, four synthetic molecules were produced. One similar to the major hexa-acylated species (BECC438s) and three hexa-acylated species designated 16:0/16:0, 14:0/16:0, and 17:0cyclo/16:0. Structural alterations are in the length and position of secondary acyl moieties. Synthetic molecules were tested for induction of NF-κB in immortalized murine and human cells
To determine in vivo efficacy, C57BL/6 mice were vaccinated intramuscularly with each structure and the recombinant Y. pestis F1-V antigen in a prime-boost model. The mice were subsequently challenged to compare the protective efficacy in comparison to PBS and F1-V alone control groups. Additionally, antibody isotyping was carried out to determine if a balanced Th1/Th2 immune response was elicited.
Results:In all cell types, the synthetic molecules showed minimal activation of hTLR4, while BECC438b activated hTLR4, mTLR4, THP-1, and RAW-Blue cell lines, though less than lipid A derived from E. coli, which is highly proinflammatory. In vivo analysis showed that BECC438b produced increased IgG2c titers after both the prime and boost vaccination when compared to Alum, MF59, and PHAD, while also providing a balanced Th1/Th2 response. This response did not vary between male and female mice. The synthetic molecules produced higher IgG2c titers than PHAD, MF59, and Alum. Interestingly, BECC438b produced a significant amount of IgG3 and IgG2b, but not IgE, as comparted to the synthetic versions.
Conclusions:Vaccination with BECC438b or BECC438s provided protection against a lethal Y. pestis challenge, as compared to the other synthetic molecules and increased IgG1 and IgG2c titers. Interestingly, two of the synthetic molecules, 16:0/16:0 and 14:0/16:0, generated increased levels of IgE.
Keyword(s): LPS, Vaccine adjuvant, TLR4 mimetic