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Vector Design for Improved DNA Vaccine Efficacy, Safety and Production.

Williams JA - Vaccines (Basel) (2013)

Bottom Line: Innovations such as electroporation, needle free jet delivery and lipid-based carriers increase transgene expression and immunogenicity through more effective gene delivery.These next generation vectors also address potential safety issues such as antibiotic selection, and increase plasmid manufacturing quality and yield in exemplary fermentation production processes.Application of optimized constructs in combination with improved delivery platforms tangibly improves the prospect of successful application of DNA vaccination as prophylactic vaccines for diverse human infectious disease targets or as therapeutic vaccines for cancer and allergy.

View Article: PubMed Central - PubMed

Affiliation: Nature Technology Corporation/Suite 103, 4701 Innovation Drive, Lincoln, NE 68521, USA. jim@natx.com.

ABSTRACT
DNA vaccination is a disruptive technology that offers the promise of a new rapidly deployed vaccination platform to treat human and animal disease with gene-based materials. Innovations such as electroporation, needle free jet delivery and lipid-based carriers increase transgene expression and immunogenicity through more effective gene delivery. This review summarizes complementary vector design innovations that, when combined with leading delivery platforms, further enhance DNA vaccine performance. These next generation vectors also address potential safety issues such as antibiotic selection, and increase plasmid manufacturing quality and yield in exemplary fermentation production processes. Application of optimized constructs in combination with improved delivery platforms tangibly improves the prospect of successful application of DNA vaccination as prophylactic vaccines for diverse human infectious disease targets or as therapeutic vaccines for cancer and allergy.

No MeSH data available.


Related in: MedlinePlus

RNA selectable marker DNA vaccine plasmids. Purple arrow in bacterial region is pUC replication origin, brown arrow in panels (a) and (c) is the RNA selection marker. Eukaryotic region promoter, transgene and polyA are depicted with orange arrow, blue arrow and green box, respectively. (a) NTC8385 plasmid borne RNA-OUT RNA binds a chromosomally encoded constitutively expressed mRNA that contains the RNA-IN target sequence in the leader. This prevents translation of the downstream levansucrase (sacB), allowing growth on sucrose media; (b) pMINI pUC origin encoded RNAI binds a chromosomally encoded constitutively expressed mRNA that contains the RNAII target sequence in the leader. In the murselect-system, an essential gene (murA) is modified to contain a repressor binding site in the promoter and the RNAII target sequence is incorporated into the repressor mRNA leader. RNAI binding to RNAII prevents repressor translation, allowing expression of the essential gene; (c) pFAR4/pCOR plasmid borne suppressor tRNA allows read-through translation of an amber nonsense codon in a chromosome encoded essential gene. Adapted from Oliveira and Mairhofer, 2013 [48].
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vaccines-01-00225-f003: RNA selectable marker DNA vaccine plasmids. Purple arrow in bacterial region is pUC replication origin, brown arrow in panels (a) and (c) is the RNA selection marker. Eukaryotic region promoter, transgene and polyA are depicted with orange arrow, blue arrow and green box, respectively. (a) NTC8385 plasmid borne RNA-OUT RNA binds a chromosomally encoded constitutively expressed mRNA that contains the RNA-IN target sequence in the leader. This prevents translation of the downstream levansucrase (sacB), allowing growth on sucrose media; (b) pMINI pUC origin encoded RNAI binds a chromosomally encoded constitutively expressed mRNA that contains the RNAII target sequence in the leader. In the murselect-system, an essential gene (murA) is modified to contain a repressor binding site in the promoter and the RNAII target sequence is incorporated into the repressor mRNA leader. RNAI binding to RNAII prevents repressor translation, allowing expression of the essential gene; (c) pFAR4/pCOR plasmid borne suppressor tRNA allows read-through translation of an amber nonsense codon in a chromosome encoded essential gene. Adapted from Oliveira and Mairhofer, 2013 [48].

Mentions: The use of any protein-based selection marker raises the concern that it may be unintentionally expressed and translated in the vaccinated organism. While a number of antibiotic-free (AF) plasmid retention systems have been developed in which the vector-encoded selection marker is not protein based [22,40] superior expression and manufacture has been observed with DNA vaccine vectors that incorporate RNA based antibiotic-free selection markers. For example, the NTC8385 sucrose selection vector (Figure 2c) encodes RNA-OUT, a small 70 bp antisense RNA (Figure 3a) [41]; pFAR4 and pCOR vectors encode a nonsense suppressor tRNA marker (Figure 3c) [42,43], while the pMINI vector utilizes the ColE1 origin-encoded RNAI antisense RNA (Figure 3b) [44,45]. These plasmid borne RNAs regulate the translation of a host chromosome encoded selectable marker allowing plasmid selection (Figure 3). Of these, high yield fermentation processes (>500 mg/L) have been developed for RNA-OUT vectors (1,800 mg/L; [46]) and pMINI (900 mg/L; [47]). In all these vectors, replacement of the kanR antibiotic selection marker resulted in increased transgene expression in the target organism (see Section 5) demonstrating elimination of antibiotic selection to meet regulatory criteria may unexpectedly also improve product performance (reviewed in [48]).


Vector Design for Improved DNA Vaccine Efficacy, Safety and Production.

Williams JA - Vaccines (Basel) (2013)

RNA selectable marker DNA vaccine plasmids. Purple arrow in bacterial region is pUC replication origin, brown arrow in panels (a) and (c) is the RNA selection marker. Eukaryotic region promoter, transgene and polyA are depicted with orange arrow, blue arrow and green box, respectively. (a) NTC8385 plasmid borne RNA-OUT RNA binds a chromosomally encoded constitutively expressed mRNA that contains the RNA-IN target sequence in the leader. This prevents translation of the downstream levansucrase (sacB), allowing growth on sucrose media; (b) pMINI pUC origin encoded RNAI binds a chromosomally encoded constitutively expressed mRNA that contains the RNAII target sequence in the leader. In the murselect-system, an essential gene (murA) is modified to contain a repressor binding site in the promoter and the RNAII target sequence is incorporated into the repressor mRNA leader. RNAI binding to RNAII prevents repressor translation, allowing expression of the essential gene; (c) pFAR4/pCOR plasmid borne suppressor tRNA allows read-through translation of an amber nonsense codon in a chromosome encoded essential gene. Adapted from Oliveira and Mairhofer, 2013 [48].
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4494225&req=5

vaccines-01-00225-f003: RNA selectable marker DNA vaccine plasmids. Purple arrow in bacterial region is pUC replication origin, brown arrow in panels (a) and (c) is the RNA selection marker. Eukaryotic region promoter, transgene and polyA are depicted with orange arrow, blue arrow and green box, respectively. (a) NTC8385 plasmid borne RNA-OUT RNA binds a chromosomally encoded constitutively expressed mRNA that contains the RNA-IN target sequence in the leader. This prevents translation of the downstream levansucrase (sacB), allowing growth on sucrose media; (b) pMINI pUC origin encoded RNAI binds a chromosomally encoded constitutively expressed mRNA that contains the RNAII target sequence in the leader. In the murselect-system, an essential gene (murA) is modified to contain a repressor binding site in the promoter and the RNAII target sequence is incorporated into the repressor mRNA leader. RNAI binding to RNAII prevents repressor translation, allowing expression of the essential gene; (c) pFAR4/pCOR plasmid borne suppressor tRNA allows read-through translation of an amber nonsense codon in a chromosome encoded essential gene. Adapted from Oliveira and Mairhofer, 2013 [48].
Mentions: The use of any protein-based selection marker raises the concern that it may be unintentionally expressed and translated in the vaccinated organism. While a number of antibiotic-free (AF) plasmid retention systems have been developed in which the vector-encoded selection marker is not protein based [22,40] superior expression and manufacture has been observed with DNA vaccine vectors that incorporate RNA based antibiotic-free selection markers. For example, the NTC8385 sucrose selection vector (Figure 2c) encodes RNA-OUT, a small 70 bp antisense RNA (Figure 3a) [41]; pFAR4 and pCOR vectors encode a nonsense suppressor tRNA marker (Figure 3c) [42,43], while the pMINI vector utilizes the ColE1 origin-encoded RNAI antisense RNA (Figure 3b) [44,45]. These plasmid borne RNAs regulate the translation of a host chromosome encoded selectable marker allowing plasmid selection (Figure 3). Of these, high yield fermentation processes (>500 mg/L) have been developed for RNA-OUT vectors (1,800 mg/L; [46]) and pMINI (900 mg/L; [47]). In all these vectors, replacement of the kanR antibiotic selection marker resulted in increased transgene expression in the target organism (see Section 5) demonstrating elimination of antibiotic selection to meet regulatory criteria may unexpectedly also improve product performance (reviewed in [48]).

Bottom Line: Innovations such as electroporation, needle free jet delivery and lipid-based carriers increase transgene expression and immunogenicity through more effective gene delivery.These next generation vectors also address potential safety issues such as antibiotic selection, and increase plasmid manufacturing quality and yield in exemplary fermentation production processes.Application of optimized constructs in combination with improved delivery platforms tangibly improves the prospect of successful application of DNA vaccination as prophylactic vaccines for diverse human infectious disease targets or as therapeutic vaccines for cancer and allergy.

View Article: PubMed Central - PubMed

Affiliation: Nature Technology Corporation/Suite 103, 4701 Innovation Drive, Lincoln, NE 68521, USA. jim@natx.com.

ABSTRACT
DNA vaccination is a disruptive technology that offers the promise of a new rapidly deployed vaccination platform to treat human and animal disease with gene-based materials. Innovations such as electroporation, needle free jet delivery and lipid-based carriers increase transgene expression and immunogenicity through more effective gene delivery. This review summarizes complementary vector design innovations that, when combined with leading delivery platforms, further enhance DNA vaccine performance. These next generation vectors also address potential safety issues such as antibiotic selection, and increase plasmid manufacturing quality and yield in exemplary fermentation production processes. Application of optimized constructs in combination with improved delivery platforms tangibly improves the prospect of successful application of DNA vaccination as prophylactic vaccines for diverse human infectious disease targets or as therapeutic vaccines for cancer and allergy.

No MeSH data available.


Related in: MedlinePlus