1. Genomic Diversity of a Globally Used, Live Attenuated Mycoplasma Vaccine
- Author
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Wesley Long, S, Klose, SM, Olaogun, OM, Disint, JF, Shil, P, Gyuranecz, M, Kreizinger, Z, Foldi, D, Catania, S, Bottinelli, M, Dall'Ora, A, Feberwee, A, van der Most, M, Andrews, DM, Underwood, GJ, Morrow, CJ, Noormohammadi, AH, Marenda, MS, Wesley Long, S, Klose, SM, Olaogun, OM, Disint, JF, Shil, P, Gyuranecz, M, Kreizinger, Z, Foldi, D, Catania, S, Bottinelli, M, Dall'Ora, A, Feberwee, A, van der Most, M, Andrews, DM, Underwood, GJ, Morrow, CJ, Noormohammadi, AH, and Marenda, MS
- Abstract
The Mycoplasma synoviae live attenuated vaccine strain MS-H (Vaxsafe MS; Bioproperties Pty., Ltd., Australia) is commonly used around the world to prevent chronic infections caused by M. synoviae in birds and to minimize economic losses in the poultry industry. MS-H is a temperature-sensitive strain that is generated via the chemical mutagenesis of a virulent M. synoviae isolate, 86079/7NS. 32 single nucleotide polymorphisms have been found in the genome of MS-H compared to that of 86079/7NS, including 25 in predicted coding sequences (CDSs). There is limited information on the stability of these mutations in MS-H in vitro during the propagation of the vaccine manufacturing process or in vivo after the vaccination of chickens. Here, we performed a comparative analysis of MS-H genomes after in vitro and in vivo passages under different circumstances. Studying the dynamics of the MS-H population can provide insights into the factors that potentially affect the health of vaccinated birds. The genomes of 11 in vitro laboratory passages and 138 MS-H bird reisolates contained a total of 254 sequence variations. Of these, 39 variations associated with CDSs were detected in more than one genome (range = 2 to 62, median = 2.5), suggesting that these sequences are particularly prone to mutations. From the 25 CDSs containing previously characterized variations between MS-H and 86079/7NS, 7 were identified in the MS-H reisolates and progenies examined here. In conclusion, the MS-H genome contains individual regions that are prone to mutations that enable the restoration of the genotype or the phenotype of wild-type 86079/7NS in those regions. However, accumulated mutations in these regions are rare. IMPORTANCE Preventative measures, such as vaccination, are commonly used for the control of mycoplasmal infections in poultry. A live attenuated vaccine strain (Vaxsafe MS; MS-H; Bioproperties Pty. Ltd., Australia) is used for the prevention of disease caused by M. synoviae in many
- Published
- 2022