Immunogenic composition of killed
The present invention pertains to a composition containing an immunogenic cell preparation of killed Leptospira bacteria in an ethylenediaminetetraacetic acid solution. The invention also pertains to a vaccine to protect an animal against an infection with leptospira bacteria, wherein the vaccine comprises this composition. Also, the invention pertains to the use of ethylenediaminetetraacetic acid to stabilize an immunogenic preparation of killed Leptospira bacteria in a liquid carrier, by dissolving the ethylenediaminetetraacetic acid in the carrier.
1. A composition containing an immunogenic cell preparation of killed Leptospira bacteria chosen from Leptospira interrogans serogroup Canicola serovar Portland-Vere, Leptospira interrogans serogroup Icterohaemorrhagiae serovar Copenhageni and Leptospira kirschneri serogroup Grippotyphosa serovar Dadas in an ethylenediaminetetraacetic acid solution, wherein the composition retains at least 25% of its antigenic mass during a 3 month storage at a temperature between 18° C. and 37° C.
2. The composition of claim 1 , wherein the solution comprises 5 to 50 mmols of ethylenediaminetetraacetic acid per liter.
3. The composition of claim 2 , wherein the solution comprises 20 mmols of ethylenediaminetetraacetic acid per liter.
4. The composition of claim 3 , wherein the solution contains dibasic sodium phosphate.
5. The composition of claim 2 , wherein the solution contains dibasic sodium phosphate.
6. The composition of claim 1 , wherein the solution contains dibasic sodium phosphate.
7. A vaccine to protect an animal against an infection with leptospira bacteria, wherein the vaccine comprises a composition of claim 6 .
8. A vaccine to protect an animal against an infection with leptospira bacteria, wherein the vaccine comprises a composition of claim 5 .
9. A vaccine to protect an animal against an infection with leptospira bacteria, wherein the vaccine comprises a composition of claim 4 .
10. A vaccine to protect an animal against an infection with leptospira bacteria, wherein the vaccine comprises a composition of claim 1 .
11. A method of stabilizing an immunogenic preparation of killed Leptospira bacteria of claim 1 in a liquid carrier, comprising dissolving ethylenediaminetetraacetic acid in the liquid carrier.