• Product Name: B. anthracis Sterne strain spore vaccine
• Manufacturer: Colorado Serum Company
• Vaccine Ontology ID: VO_0000874
• Type: Live, attenuated vaccine
• Status: Licensed
• PagA from B. anthracis str. 'Ames Ancestor' gene engineering:
  • Type: Protein
  • Detailed Gene Information: Click Here.
• Preparation: Anthrax Spore Vaccine is prepared with a relatively nonpathogenic, noncapsulated variant strain of B. anthracis, originally developed at the Onderstepoort Laboratory, Pretoria, South Africa. Further work was conducted in England, India and in many other countries. Vaccine Strain is Sterne 34F2. The vaccine is a suspension of viable Bacillus anthracis spores in saponin (Spore vaccine).

• Vaccine Ontology ID: VO_0004270
• Type: Subunit vaccine
• Status: Research
• Antigen: B. anthracis PA protein (Ivins et al., 1992).
• Adjuvant:
  • VO ID: VO_0001351
• Immunization Route: Intramuscular injection (i.m.)

• Vaccine Ontology ID: VO_0004223
• Type: Subunit vaccine
• Status: Research
• Antigen: purified rPA (Rhie et al., 2005).
• Adjuvant:
  • VO ID: VO_0001311
• Immunization Route: Intramuscular injection (i.m.)

• Vaccine Ontology ID: VO_0002775
• Type: Live, attenuated vaccine
• Status: Licensed
• mntA gene engineering:
  • Type: Gene mutation
  • Detailed Gene Information: Click Here.
• Preparation: An mntA deletion, generated by allelic replacement resulted in complete loss of MntA expression (Gat et al., 2005).
• Immunization Route: Other

• Vaccine Ontology ID: VO_0000526
• Type: Toxoid vaccine
• Antigen: For this vaccine, recombinant Bacillus anthracis protective antigen was used (Bielinska et al., 2007).
• Adjuvant:
  • VO ID: VO_0001319
• Preparation: The NE was manufactured by the emulsification of cetyl pyridum chloride, Tween 20, and ethanol in water with hot-pressed soybean oil, using a high-speed emulsifier. Every rPA-NE formulation was prepared by mixing rPA protein solution with NE, using saline as a diluent 30 to 60 min prior to immunization. For immunization with immunostimulants, 20 μg rPA was mixed with either 5 μg of MPL A or 10 μg CpG oligonucleotides in saline (Bielinska et al., 2007).

Mouse Response

• Host Strain: BALB/c
• Vaccination Protocol: Groups of mice were immunized intranasally with either one or two administrations of experimental vaccine 3 weeks apart. rPA-NE mixes were applied to the nares with a pipette tip administering 10 μl per nare, and the animals were then allowed to inhale the material (Bielinska et al., 2007).
• Immune Response: rPA-NE immunization was effective in inducing both serum anti-PA IgG and bronchial anti-PA IgA and IgG antibodies after either one or two mucosal administrations. Serum anti-PA IgG2a and IgG2b antibodies and PA-specific cytokine induction after immunization indicate a Th1-polarized immune response. rPA-NE immunization also produced high titers of lethal-toxin-neutralizing serum antibodies in mice (Bielinska et al., 2007).
• Challenge Protocol: The immune responses of mice were not challenged.

Guinea pig Response

• Host Strain: Female Hartley guinea pigs
• Vaccination Protocol: Three 0.5-ml doses of the PA vaccine were administered at 2-week intervals. The commercial live veterinary Sterne strain spore vaccine was administered in three doses: 0.2, 0.3, and 0.5 ml i.m. at 2-week intervals. The stock spore vaccine contained 5 x 10^6 to 6 x 10^6 spores per ml (Little et al., 1986).
• Immune Response: A high ELISA titer was obtained after immunization, as demonstrated by immunization with Sterne strain spores or PA vaccine + LF. However, it did not reflect the level of expected protection. This was demonstrated after challenge with a vaccine-resistant isolate. Comparison of the vaccine-resistant isolates with the Vollum cultures suggested that it is not the difference in the LD50s of the isolates that determines vaccine resistance but some other factors (Little et al., 1986).
• Challenge Protocol: The animals were then challenged i.m. with 2,500 spores of Vollum 1B 2 weeks after immunization.
• Efficacy: With Vollum and Vollum 1B, strains of B. anthracis killed 50% or more of the PA-immunized animals. The data confirm earlier findings: although guinea pigs were immunized effectively against a Vollum challenge, they were not protected against challenge with some isolates of B. anthracis. The study tested 4 of the10 strains used from the earlier study challenging their guinea pigs. In total 9 of 27 isolates tested were found to be resistant to immunization with the PA vaccine. Vaccination of guinea pigs with Sterne strain spores appears to provide broad protection against i.m. challenge with various anthrax isolates. A dose-response curve of the Sterne spore vaccine was obtained by injecting guinea pigs with 0.5 ml i.m. in a single dose or as two doses 14 days apart. The data indicate that excellent protection and antibody response to PA antigen can be achieved with two immunization doses of 10^6 Sterne spores (Little et al., 1986).
• Description: Although various antigen preparations appear to provide a substantial degree of protection when immunized animals are challenged with the standard Vollum strain, earlier studies demonstrated that certain B. anthracis isolates were able to override this immunity in guinea pigs. This current study seeks an overall effort to evaluate and improve the PA vaccine presently used for humans and to confirm and expand upon those earlier studies (Little et al., 1986).

Guinea pig Response

• Host Strain: Hartley
• Vaccination Protocol: Several adjuvant preparations combined with PA were compared with each other and with MDPH-PA with respect to protection and elicitation of anti-PA antibody. In the first experiment, guinea pigs received one or more injections of each preparation (Ivins et al., 1992).
• Challenge Protocol: Guinea pigs were challenged i.m. 10 weeks after the first immunization with 7,300 (73 LD50) of B. anthracis Ames spores (Ivins et al., 1992).
• Efficacy: 12/18 guinea pigs survived challenge after immunization with 1 dose of PA + TMDP and 13/20 survived after 2 doses of PA + TMDP (Ivins et al., 1992).

Guinea pig Response

• Host Strain: Hartley
• Vaccination Protocol: Groups of female Hartley guinea pigs (Damul Science, Korea) weighing 300–320 g were immunized by intramuscular injection on days 0, 14, and 28 with 50 μg of the purified rPA. rPA was dissolved in 500 μl PBS containing Rehydragel HPA (alum hydroxide fluid gel, 250 μg; Reheis Inc., USA), according to the manufacturer's protocol. Phosphate-buffered saline (PBS) was used as a negative control (Rhie et al., 2005).
• Challenge Protocol: Fourteen days after the third immunization, the guinea pigs were challenged with 100 LD50 of B. anthracis ATCC14578 spores by intramuscular injection. After injection with B. anthracis spores, guinea pigs were observed for a period of 14 days. Animals surviving for 14 days after the challenge were considered survivors (Rhie et al., 2005).
• Efficacy: Guinea pigs immunized with rPA + Rehydragel HPA had 100% survival rate to challenge with B. anthracis ATCC14578 spores (Rhie et al., 2005).

Guinea pig Response

• Persistence: The mntA mutant resulted in severe attenuation; a 10(4)-fold drop in LD(50) in a guinea pig model (Gat et al., 2005).
• Efficacy: All the guinea pigs were challenged with 60 LD50 of the virulent Vollum strain. All guinea pigs survived this challenge and exhibited antibody titers 103−105 of either anti-PA or anti-LF (Gat et al., 2005).

Guinea pig Response

• Host Strain: Hartley
• Vaccination Protocol: Hartley guinea pigs were vaccinated intranasally with one or two administrations of vaccine, each about 50 μl per nare, 4 weeks apart (Bielinska et al., 2007).
• Immune Response: serum anti-PA immunoglobulin G and bronchial anti-PA IgA and IgG antibodies were produced following either one of two mucosal immunizations of rPA-NE. The anti-PA IgG2a and IgG2b antibodies and PA-specific cytokine induction found in the serum indicated a Th-1-polarized immune response. High titers of lethal-toxin-neatralizing antibodies were also found after rPA-NE immunization (Bielinska et al., 2007).
• Challenge Protocol: The guinea pigs were challenged intradermaly with ~1,000 times the 50% lethal dose of B. anthracis Ames strain spores, which was about 1.38 × 10^3 spores (Bielinska et al., 2007).
• Efficacy: Nasal immunization resulted in 70% and 40% survival rates against intranasal challenge with 1.2 × 10^6 and 1.2 × 10^7 Ames strain spores (Bielinska et al., 2007).