- Email: [email protected]
148. Multivalent Adenovector-Based Malaria Vaccine Induces High Levels of Functional Antibodies
immune responses elicited by a number of different DNA vaccines in conjunctionwith constant-currentelectroporation(CCE) in mice, rabbits and non-human primates. Administration of I-IIY or SIV expression vectors with CCE significantly improved antibody titers and cell-mediatedimmunityas comparedto 1M injectionalone in all species tested. In mice, the expression levels after 1M injection of Hlv-cxprcssing plasmids and CCE were IOO-fold higher compared to 1M alone. Anti-env titers were two-fold higher in eleetroporated rabbits receiving SlY plasmids as compared to 1M injection alone. Sera from both rabbits and non-human primates were shown to neutralizeSI·IIYisolates. IsolatedPBMCsfrom non-human primates also demonstrated potent cellular immunity as measured by IFN-y ELlSpot assay. ln a study in non-human primates, all animals that had received the HIV antigens with CCE had positive HIY gag and env ELlSpot results two weeks after a single immunization. The average HIV gag ELISpot count for the elcetroporated group was 200 spots per million PBMCs after a single 1Minjection with CCE. This is significant considering that the average ELlSpot response for HIV gag was 300 spots per million PBMCs following three 1M injections. Following a second immunization using CCE after 4 weeks, the average ELlSpot count was 1000for gag and env which was about 15to 20 times higher than 1Malone. Significantlyhigher cellular and humoral responses in mice, rabbits and non-human primates demonstratethat using the CCE delivery method dramatically improvesimmunogenicity and the effectiveness of DNAvaccination. The significantimmune responsesexhibited in largeranimal models in these studies provide pre-clinical evidence that CCE may be a useful tool to effectively deliver DNA vaccines to humans.
147. Novel Strategy for Generation of Mucosal Immune Responses Against HIV-1 Following Systemic Vaccination MicheleA . Kutzler,' Kimberly A. Schoenly,' Karuppiah Muthumanl ,' Rose M. Parkinson,' Henry Maguire,' Kenneth Ugcn,' David B. Weincr.I
'The Department ofPathology and Laboratory Medicine , University ofPennsylvania, Philadelphia, PA; 1711e Department ofMedical Microbiology and Immunology; University ofSouth Florida, Tampa, FL.
A significant hurdle in effective vaccine design for infectious pathogens is the ability to mount immune responses at the portal of entry, namely mucosal sites. The development of a systemicdelivered vaccine approach driving secretory IgA and mucosal T cell immune responses against pathogens would fundamentally change many vaccine strategies. Using mucosal pathogens HIY-I and InfIuenzaAas models, we demonstratethat a novel systemic administeredDNAvaccinationstrategyutilizingco-deliveryof specific mucosal-derived chemokine adjuvants, can produce distal mucosal immune responses.This strategy resulted in redirection ofa4b7 and CCR9 or CCR I 0 positive immune cells to the site of immunization with mucosal retrafficking phenotype. The immune phenotype included enhanced cytokine and cytolytic markers expressed by antigen-specific T cells from the spleen, lung and lamina propria, as well as elevated [gG and secretory IgA responses in secondary lymphoid organs, B cells from the gut, peripheral blood and fecal extracts. Systemic immunization controls, as expected, failed to inducemucosal immunity. These studeics have great significancefor basic understandingof gut lymphocytehoming, mucosal phenotype commitment, and development of vaccine strategies for mucosal pathogens. This work is supported by F32AI054152 to MAK, and NOI-AI-15429, NIAID-HVDDTto DBW.
Molecular Therapy Volume \5. Supplement I, M'l' 2007
C;oppight © T be American Soci ety of Gene Therapy
148. Multivalent Adenovector-Based Malaria Vaccine Induces High Levels of Functional Antibodies
Joseph T. Bruder,' Ping Chen, I Svetlana Konovalova,' Keith Limbach,' Damodar Ettyreddy,' Maureen E. Stefaniak.' Noelle B. Patterson,' Joseph J. Campo,' Sheng Li,3 C. R. King,I Carole A. Long,' Denise L. Doolan.' I Research, Gen Vee. Gaithersburg. M D; "Malaria Program. Naval Medical Research Center; Silver Spring, MD; "Malaria Vaccine Initiative, PATH, Bethesda. MD; "Laboratory ofMalaria and Vector Research, NIAID/NIH, Rockville, MD.
Malaria is the mostdevastatingparasiticdiseaseaffectinghumans. Each year, there are 350-500 million clinical cases and greater than one million deaths due to malaria, primarily of children in subSaharan Africa. The feasibility of a blood-stage malaria vaccine is supported by the finding that individuals living in malaria-endemic communities develop clinical immunity to the parasite, and that passive transfer of immunoglobulin from such individuals results in a marked decrease in Efalciporum blood-stage parasitemia and resolution of symptoms. To reduce manufacturing costs for a vaccine for the developing world and to increase vaccine breadth and potency, our development strategy is to combine multiple antigens targeted by protective immune responses into a single, multivalent adenovector. One approachhas been to developa bivalentadenovector that expresses optimized forms oftwo P.falciparum blood-stage antigens, which are targets of naturally acquired immunity. In the optimization stage, we tested whether intracellular,secreted glycosylatcd, or secreted non-glycosylatcd forms of mammalian codonoptimized PfAMA I and PjMSP142 induced superior antibody and T cell responses in mice and rabbits.Adenovector-deliveredPfAMA I induced high ELISA titers in mice and high titers of functional antibodies in rabbits:greaterthan 95% inhibitionwas achievedusing2.5 mg/ml of purified IgG. The secreted glycosylated and the secreted non-glycosylated versions of PfAMA I induced equally high levels of functional antibodies. Adenovector-delivered PjMSP 142 also induccd high ELISAtiters in mice and functional antibody responses in rabbits, however, the relative levels of GIA activity were lower than those observed with the PfAMA I-expressing vector.The most robust responses were seen in animals immunized with the secreted Antigens that were expressed glycosylated versions of I'lMSPl~2" at the cell surface in either aglycosylated or non-glycosylated form were much better than intracellular antigens at inducing antibody responses. In contrast, T cell responses were not greatly affected by the cellular locationand glycosylation status of the antigens. Based on induction of functional antibody responses in rabbits, we chose secreted glycosylated versions of both PfAMAI and PjMSPI~2for inclusionin a bivalentadenovector. Weevaluated immune responses induced by this adenovector in mice and rabbits. For both T cell and antibody responses, the bivalent adenovector induced responses to each antigen that were comparable to the single antigen expression vectors. Interestingly, usingthis vector in a homologousprime-boost regimen, we were able to boost antibody responses by -10 fold relative to responses observed following a single administration. These results support the advancement of this bivalent, blood-stage adenoveetor vaccine to clinical development.
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147. Novel Strategy for Generation of Mucosal Immune Responses Against HIV-1 Following Systemic Vaccination MicheleA . Kutzler,' Kimberly A. Schoenly,' Karuppiah Muthumanl ,' Rose M. Parkinson,' Henry Maguire,' Kenneth Ugcn,' David B. Weincr.I
'The Department ofPathology and Laboratory Medicine , University ofPennsylvania, Philadelphia, PA; 1711e Department ofMedical Microbiology and Immunology; University ofSouth Florida, Tampa, FL.
A significant hurdle in effective vaccine design for infectious pathogens is the ability to mount immune responses at the portal of entry, namely mucosal sites. The development of a systemicdelivered vaccine approach driving secretory IgA and mucosal T cell immune responses against pathogens would fundamentally change many vaccine strategies. Using mucosal pathogens HIY-I and InfIuenzaAas models, we demonstratethat a novel systemic administeredDNAvaccinationstrategyutilizingco-deliveryof specific mucosal-derived chemokine adjuvants, can produce distal mucosal immune responses.This strategy resulted in redirection ofa4b7 and CCR9 or CCR I 0 positive immune cells to the site of immunization with mucosal retrafficking phenotype. The immune phenotype included enhanced cytokine and cytolytic markers expressed by antigen-specific T cells from the spleen, lung and lamina propria, as well as elevated [gG and secretory IgA responses in secondary lymphoid organs, B cells from the gut, peripheral blood and fecal extracts. Systemic immunization controls, as expected, failed to inducemucosal immunity. These studeics have great significancefor basic understandingof gut lymphocytehoming, mucosal phenotype commitment, and development of vaccine strategies for mucosal pathogens. This work is supported by F32AI054152 to MAK, and NOI-AI-15429, NIAID-HVDDTto DBW.
Molecular Therapy Volume \5. Supplement I, M'l' 2007
C;oppight © T be American Soci ety of Gene Therapy
148. Multivalent Adenovector-Based Malaria Vaccine Induces High Levels of Functional Antibodies
Joseph T. Bruder,' Ping Chen, I Svetlana Konovalova,' Keith Limbach,' Damodar Ettyreddy,' Maureen E. Stefaniak.' Noelle B. Patterson,' Joseph J. Campo,' Sheng Li,3 C. R. King,I Carole A. Long,' Denise L. Doolan.' I Research, Gen Vee. Gaithersburg. M D; "Malaria Program. Naval Medical Research Center; Silver Spring, MD; "Malaria Vaccine Initiative, PATH, Bethesda. MD; "Laboratory ofMalaria and Vector Research, NIAID/NIH, Rockville, MD.
Malaria is the mostdevastatingparasiticdiseaseaffectinghumans. Each year, there are 350-500 million clinical cases and greater than one million deaths due to malaria, primarily of children in subSaharan Africa. The feasibility of a blood-stage malaria vaccine is supported by the finding that individuals living in malaria-endemic communities develop clinical immunity to the parasite, and that passive transfer of immunoglobulin from such individuals results in a marked decrease in Efalciporum blood-stage parasitemia and resolution of symptoms. To reduce manufacturing costs for a vaccine for the developing world and to increase vaccine breadth and potency, our development strategy is to combine multiple antigens targeted by protective immune responses into a single, multivalent adenovector. One approachhas been to developa bivalentadenovector that expresses optimized forms oftwo P.falciparum blood-stage antigens, which are targets of naturally acquired immunity. In the optimization stage, we tested whether intracellular,secreted glycosylatcd, or secreted non-glycosylatcd forms of mammalian codonoptimized PfAMA I and PjMSP142 induced superior antibody and T cell responses in mice and rabbits.Adenovector-deliveredPfAMA I induced high ELISA titers in mice and high titers of functional antibodies in rabbits:greaterthan 95% inhibitionwas achievedusing2.5 mg/ml of purified IgG. The secreted glycosylated and the secreted non-glycosylated versions of PfAMA I induced equally high levels of functional antibodies. Adenovector-delivered PjMSP 142 also induccd high ELISAtiters in mice and functional antibody responses in rabbits, however, the relative levels of GIA activity were lower than those observed with the PfAMA I-expressing vector.The most robust responses were seen in animals immunized with the secreted Antigens that were expressed glycosylated versions of I'lMSPl~2" at the cell surface in either aglycosylated or non-glycosylated form were much better than intracellular antigens at inducing antibody responses. In contrast, T cell responses were not greatly affected by the cellular locationand glycosylation status of the antigens. Based on induction of functional antibody responses in rabbits, we chose secreted glycosylated versions of both PfAMAI and PjMSPI~2for inclusionin a bivalentadenovector. Weevaluated immune responses induced by this adenovector in mice and rabbits. For both T cell and antibody responses, the bivalent adenovector induced responses to each antigen that were comparable to the single antigen expression vectors. Interestingly, usingthis vector in a homologousprime-boost regimen, we were able to boost antibody responses by -10 fold relative to responses observed following a single administration. These results support the advancement of this bivalent, blood-stage adenoveetor vaccine to clinical development.
S57