US 11,872,256 B2
Bacteriophage composition and method of preventing bacterial infections in livestock
Rodrigue Dubar, Québec (CA); and Simon Labrie, Québec (CA)
Assigned to SYNTBIOLAB INC., Lévis (CA)
Appl. No. 16/647,445
Filed by SYNTBIOLAB INC., Lévis (CA)
PCT Filed Sep. 14, 2018, PCT No. PCT/CA2018/051141
§ 371(c)(1), (2) Date Mar. 13, 2020,
PCT Pub. No. WO2019/051603, PCT Pub. Date Mar. 21, 2019.
Claims priority of provisional application 62/558,924, filed on Sep. 15, 2017.
Prior Publication US 2021/0008133 A1, Jan. 14, 2021
Int. Cl. A61K 35/76 (2015.01); A23K 10/18 (2016.01); A61P 31/04 (2006.01); C12N 7/00 (2006.01)
CPC A61K 35/76 (2013.01) [A23K 10/18 (2016.05); A61P 31/04 (2018.01); C12N 7/00 (2013.01); C12N 2795/00032 (2013.01); C12N 2795/00051 (2013.01)] 18 Claims
 
1. A method for manufacturing a bacteriophage cocktail comprising at least two bacteriophage strains for the prevention of an opportunistic bacterial infection caused by pathogenic bacterial cells in livestock, the method comprising:
a) characterizing at least two bacteriophage strains based on:
(i) an absence of a gene encoding an integrase;
(ii) an absence of a 16s rRNA gene marker;
(iii) an absence of a gene encoding a human toxin;
(iv) an absence of an antibiotic resistance gene;
(v) a burst size greater than 10 against said pathogenic bacterial cells;
(vi) stability at pH 4;
(vii) stability at a temperature between 4° C. and room temperature (RT); and
(viii) an absence of cross-resistance by said pathogenic bacterial cells against at least two bacteriophage strains by:
providing a first and a second bacteriophage strain that infect the Pathogenic bacteria, the second bacteriophage strain being different from the first bacteriophage strain;
culturing the first bacteriophage strain in the presence of said pathogenic bacteria at a Multiplicity of Infection (MOI) of at least about 1 until said bacteria develop resistance to the first bacteriophage strain, thereby producing a Bacteriophage Insensitive Mutant (BIM) pathogenic bacterial strain;
challenging the BIM pathogenic bacterial strain with the second bacteriophage strain; and
determining the absence of cross-resistance when the second bacteriophage strain still inhibits the growth of the BIM pathogenic bacterial strain; and
b) selecting at least two bacteriophage strains characterized based on each of (i)-(viii) in step a), and combining to form the cocktail.