1887

Microbial Genomics logo

Volume 9, Issue 8

Mapping the phylogeny and lineage history of geographically distinct BCG vaccine strains Open Access

Abstract

The bacillus Calmette–Guérin (BCG) vaccine has been in use for prevention of tuberculosis for over a century. It remains the only widely available tuberculosis vaccine and its protective efficacy has varied across geographical regions. Since it was developed, the BCG vaccine strain has been shared across different laboratories around the world, where use of differing culture methods has resulted in genetically distinct strains over time. Whilst differing BCG vaccine efficacy around the world is well documented, and the reasons for this may be multifactorial, it has been hypothesized that genetic differences in BCG vaccine strains contribute to this variation. Isolates from an historic archive of lyophilized BCG strains were regrown, DNA was extracted and then whole-genome sequenced using Oxford Nanopore Technologies. The resulting whole-genome data were plotted on a phylogenetic tree and analysed to identify the presence or absence of regions of difference (RDs) and single-nucleotide polymorphisms (SNPs) relating to virulence, growth and cell wall structure. Of 50 strains available, 36 were revived in culture and 39 were sequenced. Morphology differed between the strains distributed before and after 1934. There was phylogenetic association amongst certain geographically classified strains, most notably BCG-Russia, BCG-Japan and BCG-Danish. RD2, RD171 and RD713 deletions were associated with late strains (seeded after 1927). When mapped to BCG-Pasteur 1172, the SNPs in , , and were associated with early strains. Whilst BCG-Russia, BCG-Japan and BCG-Danish showed strong geographical isolate clustering, the late strains, including BCG-Pasteur, showed more variation. A wide range of SNPs were seen within geographically classified strains, and as much intra-strain variation as between-strain variation was seen. The date of distribution from the original Pasteur laboratory (early pre-1927 or late post-1927) gave the strongest association with genetic differences in regions of difference and virulence-related SNPs, which agrees with the previous literature.

  • Received:
  • Accepted:
  • Published Online:
Keyword(s): BCG , long read , Oxford Nanopore Technologies , strain , tuberculosis , vaccine and whole-genome sequencing
Funding
This study was supported by the:
  • European and Developing Countries Clinical Trials Partnership (Award CSA2020NoE-3100)
    • Principle Award Recipient: NotApplicable
© 2023 The Authors
  • This is an open-access article distributed under the terms of the Creative Commons Attribution License. This article was made open access via a Publish and Read agreement between the Microbiology Society and the corresponding author’s institution.
Loading

Article metrics loading...

/content/journal/mgen/10.1099/mgen.0.001077
2023-08-01
2024-05-18
Loading full text...

Full text loading...

/deliver/fulltext/mgen/9/8/mgen001077.html?itemId=/content/journal/mgen/10.1099/mgen.0.001077&mimeType=html&fmt=ahah

References

  1. TBfacts.org BCG Vaccine; 2020 https://tbfacts.org/bcg-vaccine/ accessed 28 June 2021
  2. Oettinger T, Jørgensen M, Ladefoged A, Hasløv K, Andersen P. Development of the Mycobacterium bovis BCG vaccine: review of the historical and biochemical evidence for a genealogical tree. Tuber Lung Dis 1999; 79:243–250 [View Article] [PubMed]
     [Google Scholar]
  3. Liu J, Tran V, Leung AS, Alexander DC, Zhu B. BCG vaccines: their mechanisms of attenuation and impact on safety and protective efficacy. Hum Vaccin 2009; 5:70–78 [View Article] [PubMed]
     [Google Scholar]
  4. Yamamoto S, Yamamoto T. Historical review of BCG vaccine in Japan. Jpn J Infect Dis 2007; 60:331–336 [PubMed]
     [Google Scholar]
  5. Mokrousov I, Vyazovaya A, Potapova Y, Vishnevsky B, Otten T et al. Mycobacterium bovis BCG-Russia clinical isolate with noncanonical spoligotyping profile. J Clin Microbiol 2010; 48:4686–4687 [View Article] [PubMed]
     [Google Scholar]
  6. Osborn TW. Changes in BCG strains. Tubercle 1983; 64:1–13 [View Article] [PubMed]
     [Google Scholar]
  7. Ritz N, Hanekom WA, Robins-Browne R, Britton WJ, Curtis N. Influence of BCG vaccine strain on the immune response and protection against tuberculosis. FEMS Microbiol Rev 2008; 32:821–841 [View Article] [PubMed]
     [Google Scholar]
  8. Paiman SA, Siadati A, Mamishi S, Tabatabaie P. Disseminated Mycobacterium bovis infection after BCG vaccination. Iran J Allergy, Asthma and Immunol 2006; 5:133–137
     [Google Scholar]
  9. Elias D, Akuffo H, Pawlowski A, Haile M, Schön T et al. Schistosoma mansoni infection reduces the protective efficacy of BCG vaccination against virulent Mycobacterium tuberculosis. . Vaccine 2005; 23:1326–1334 [View Article] [PubMed]
     [Google Scholar]
  10. Tangie E, Walters A, Hsu N-J, Fisher M, Magez S et al. BCG-mediated protection against M. tuberculosis is sustained post-malaria infection independent of parasite virulence. Immunology 2022; 165:219–233 [View Article] [PubMed]
     [Google Scholar]
  11. Faurholt-Jepsen D, Range N, Praygod G, Jeremiah K, Faurholt-Jepsen M et al. BCG protects against tuberculosis irrespective of HIV status: a matched case-control study in Mwanza, Tanzania. Thorax 2013; 68:288–289 [View Article] [PubMed]
     [Google Scholar]
  12. Fine PEM. Variation in protection by BCG: implications of and for heterologous immunity. Lancet 1995; 346:1339–1345 [View Article] [PubMed]
     [Google Scholar]
  13. Moliva JI, Turner J, Torrelles JB. Prospects in Mycobacterium bovis Bacille Calmette et Guérin (BCG) vaccine diversity and delivery: why does BCG fail to protect against tuberculosis?. Vaccine 2015; 33:5035–5041 [View Article] [PubMed]
     [Google Scholar]
  14. Milstien J, Gibson J. Quality control of BCG vaccines by the world health organization: a review of factors that may influence vaccine efectiveness and safety; 19891–30
  15. Guallar-Garrido S, Almiñana-Rapún F, Campo-Pérez V, Torrents E, Luquin M et al. BCG substrains change their outermost surface as a function of growth media. Vaccines 2021; 10:40 [View Article] [PubMed]
     [Google Scholar]
  16. Mangtani P, Abubakar I, Ariti C, Beynon R, Pimpin L et al. Protection by BCG vaccine against tuberculosis: a systematic review of randomized controlled trials. Clin Infect Dis 2014; 58:470–480 [View Article] [PubMed]
     [Google Scholar]
  17. Angelidou A, Conti M-G, Diray-Arce J, Benn CS, Shann F et al. Licensed Bacille Calmette-Guérin (BCG) formulations differ markedly in bacterial viability, RNA content and innate immune activation. Vaccine 2020; 38:2229–2240 [View Article] [PubMed]
     [Google Scholar]
  18. Abdallah AM, Hill-Cawthorne GA, Otto TD, Coll F, Guerra-Assunção JA et al. Genomic expression catalogue of a global collection of BCG vaccine strains show evidence for highly diverged metabolic and cell-wall adaptations. Sci Rep 2015; 5:1–5 [View Article] [PubMed]
     [Google Scholar]
  19. Ludannyy R, Alvarez Figueroa M, Levi D, Markelov M, Dedkov V et al. Whole-genome sequence of Mycobacterium bovis BCG-1 (Russia). Genome Announc 2015; 3:7–8 [View Article] [PubMed]
     [Google Scholar]
  20. Lind A. The Swedish strain of BCG. Tubercle 1983; 64:223–224 [View Article] [PubMed]
     [Google Scholar]
  21. Seki M, Honda I, Fujita I, Yano I, Yamamoto S et al. Whole genome sequence analysis of Mycobacterium bovis Bacillus Calmette-Guérin (BCG) Tokyo 172: a comparative study of BCG vaccine substrains. Vaccine 2009; 27:1710–1716 [View Article] [PubMed]
     [Google Scholar]
  22. Frappier A, Panisset M. La souche du BCG. In Monographie de l’Institut de Microbiologie et d’Hygiène de l’Université de Montréal 1957
     [Google Scholar]
  23. Birkhaug K. Virulence and tuberculogenic studies of 60 consecutive weekly lots of BCG vaccine produced by standard technique. Am Rev Tuberc 1949; 59:567–588 [View Article] [PubMed]
     [Google Scholar]
  24. Kozak RA, Alexander DC, Liao R, Sherman DR, Behr MA. Region of difference 2 contributes to virulence of Mycobacterium tuberculosis. Infect Immun 2011; 79:59–66 [View Article] [PubMed]
     [Google Scholar]
  25. Behr MA, Schroeder BG, Brinkman JN, Slayden RA, Barry CE. A point mutation in the mma3 gene is responsible for impaired methoxymycolic acid production in Mycobacterium bovis BCG strains obtained after 1927. J Bacteriol 2000; 182:3394–3399 [View Article] [PubMed]
     [Google Scholar]
  26. Stainer DW, Landi S. Stability of BCG vaccines. Dev Biol Stand 1986; 58:119–125 [PubMed]
     [Google Scholar]
  27. Dubos RJ, Pierce CH. Tice strains of BCG. In American Review of Tuberculosis and Pulmonary Diseases vol 75 1957 p 4
     [Google Scholar]
  28. Smith D, Harding G, Chan J, Edwards M, Hank J et al. Potency of 10 BCG vaccines as evaluated by their influence on the bacillemic phase of experimental airborne tuberculosis in guinea-pigs. J Biol Stand 1979; 7:179–197 [View Article] [PubMed]
     [Google Scholar]
  29. Borgers K, Ou J-Y, Zheng P-X, Tiels P, Van Hecke A et al. Reference genome and comparative genome analysis for the WHO reference strain for Mycobacterium bovis BCG Danish, the present tuberculosis vaccine. BMC Genomics 2019; 20:1–14 [View Article] [PubMed]
     [Google Scholar]
  30. Gheorghiu M, Augier J, Lagrange P. Maintenance and control of the French BCG strain 1173-P2 (primary and secondary seed-lots. Bull Inst Pasteur 1983
     [Google Scholar]
  31. Media R. BCG’s lost luggage’ may hold a big key; 1999 https://www.reliasmedia.com/articles/50039-bcg-8217-s-lost-8216-luggage-8217-may-hold-a-big-key accessed 10 March 2022
  32. Tran V, Ahn SK, Ng M, Li M, Liu J. Loss of lipid virulence factors reduces the efficacy of the BCG vaccine. Sci Rep 2016; 6:1–12 [View Article] [PubMed]
     [Google Scholar]
  33. Forrellad MA, Klepp LI, Gioffré A, Sabio y García J, Morbidoni HR et al. Virulence factors of the Mycobacterium tuberculosis complex. Virulence 2013; 4:3–66 [View Article] [PubMed]
     [Google Scholar]
  34. Liu J, Tran V, Leung AS, Alexander DC, Zhu B. BCG vaccines: their mechanisms of attenuation and impact on safety and protective efficacy. Hum Vaccin 2009; 5:70–78 [View Article] [PubMed]
     [Google Scholar]
  35. Copin R, Coscollá M, Efstathiadis E, Gagneux S, Ernst JD. Impact of in vitro evolution on antigenic diversity of Mycobacterium bovis Bacillus Calmette-Guerin (BCG). Vaccine 2014; 32:5998–6004 [View Article] [PubMed]
     [Google Scholar]
  36. Kozak R, Behr MA. Divergence of immunologic and protective responses of different BCG strains in a murine model. Vaccine 2011; 29:1519–1526 [View Article] [PubMed]
     [Google Scholar]
  37. Wu B, Huang C, Garcia L, Ponce de Leon A, Osornio JS et al. Unique gene expression profiles in infants vaccinated with different strains of Mycobacterium bovis Bacille Calmette-Guerin. Infect Immun 2007; 75:3658–3664 [View Article] [PubMed]
     [Google Scholar]
  38. Davids V, Hanekom WA, Mansoor N, Gamieldien H, Gelderbloem SJ et al. The effect of Bacille Calmette-Guérin vaccine strain and route of administration on induced immune responses in vaccinated infants. J Infect Dis 2006; 193:531–536 [View Article] [PubMed]
     [Google Scholar]
  39. Aguirre-Blanco AM, Lukey PT, Cliff JM, Dockrell HM. Strain-dependent variation in Mycobacterium bovis BCG-induced human T-cell activation and gamma interferon production in vitro. Infect Immun 2007; 75:3197–3201 [View Article] [PubMed]
     [Google Scholar]
  40. Hengster P, Schnapka J, Fille M, Menardi G. Occurrence of suppurative lymphadenitis after a change of BCG vaccine. Arch Dis Child 1992; 67:952–955 [View Article] [PubMed]
     [Google Scholar]
  41. Castillo-Rodal AI, Castañón-Arreola M, Hernández-Pando R, Calva JJ, Sada-Díaz E et al. Mycobacterium bovis BCG substrains confer different levels of protection against Mycobacterium tuberculosis infection in a BALB/c model of progressive pulmonary tuberculosis. Infect Immun 2006; 74:1718–1724 [View Article] [PubMed]
     [Google Scholar]
  42. Kernodle DS. Decrease in the effectiveness of Bacille Calmette-Guérin vaccine against pulmonary tuberculosis: a consequence of increased immune suppression by microbial antioxidants, not overattenuation. Clin Infect Dis 2010; 51:177–184 [View Article] [PubMed]
     [Google Scholar]
  43. Chen JM, Islam ST, Ren H, Liu J. Differential productions of lipid virulence factors among BCG vaccine strains and implications on BCG safety. Vaccine 2007; 25:8114–8122 [View Article] [PubMed]
     [Google Scholar]
  44. WHO Recommendations to assure the quality, safety and efficacy of BCG vaccines. In WHO Technical Report Series vol 979 2013 pp 137–185
     [Google Scholar]
  45. World Health Organization. In WHO Technical Report Series No. 8, WHO-Sponsorted International Quality Control of BCG Vaccine 1977
     [Google Scholar]
  46. World Health Organization WHO Expert Committee on Biological Standardization, Requirements for Dried BCG Vaccine (Requirements for Biological Substances No. 11) 1985
     [Google Scholar]
  47. World Health Organization. In Information Sheet on Bacille Calmette-Guerin 2012
     [Google Scholar]
  48. NIBSC and WHO WHO Consultation on the Characterization of BCG Vaccines 2004
     [Google Scholar]
  49. Luca S, Mihaescu T. History of BCG vaccine. Maedica 2013; 8:53–58
     [Google Scholar]
  50. Zwerling A, Behr MA, Verma A, Brewer TF, Menzies D et al. The BCG world atlas: a database of global BCG vaccination policies and practices. PLoS Med 2011; 8:e1001012 [View Article] [PubMed]
     [Google Scholar]
  51. BCG World Atlas (3rd edition) 2020 http://www.bcgatlas.org/ accessed 28 June 2021
     [Google Scholar]
  52. Anisimov AP, Chen F. The bioinformatics analysis of comparative genomics of Mycobacterium tuberculosis complex (MTBC) provides insight into dissimilarities between intraspecific groups differing in host association, virulence, and epitope diversity. Front Cell Infect Microbiol 2017; 7:1–14 [View Article] [PubMed]
     [Google Scholar]
  53. Kent L, McHugh TD, Billington O, Dale JW, Gillespie SH. Demonstration of homology between IS6110 of Mycobacterium tuberculosis and DNAs of other Mycobacterium spp.?. J Clin Microbiol 1995; 33:2290–2293 [View Article] [PubMed]
     [Google Scholar]
  54. Oxford Nanopore Technologies Rapid PCR Barcoding Kit (SQK-RPB004) protocol; 2020 https://community.nanoporetech.com/protocols/rapid-pcr-barcoding/checklist_example.pdf accessed 28 June 2021
  55. Ewels P, Magnusson M, Lundin S, Käller M. MultiQC: summarize analysis results for multiple tools and samples in a single report. Bioinformatics 2016; 32:3047–3048 [View Article] [PubMed]
     [Google Scholar]
  56. Babraham Bioinformatics FastQC; 2019 https://www.bioinformatics.babraham.ac.uk/projects/fastqc/ accessed 28 June 2021
  57. Li H, Birol I. Minimap2: pairwise alignment for nucleotide sequences. Bioinformatics 2018; 34:3094–3100 [View Article] [PubMed]
     [Google Scholar]
  58. Li H, Handsaker B, Wysoker A, Fennell T, Ruan J et al. The sequence alignment/map format and SAMtools. Bioinformatics 2009; 25:2078–2079 [View Article] [PubMed]
     [Google Scholar]
  59. Danecek P, McCarthy SA. BCFtools/csq: haplotype-aware variant consequences. Bioinformatics 2017; 33:2037–2039 [View Article] [PubMed]
     [Google Scholar]
  60. Cingolani P, Platts A, Wang LL, Coon M, Nguyen T et al. A program for annotating and predicting the effects of single nucleotide polymorphisms, SnpEff: SNPs in the genome of Drosophila melanogaster strain w1118; iso-2; iso-3. Fly 2012; 6:80–92 [View Article] [PubMed]
     [Google Scholar]
  61. Bespiatykh D, Bespyatykh J, Mokrousov I, Shitikov E, Stallings CL. A comprehensive map of Mycobacterium tuberculosis complex regions of difference. mSphere 2021; 6:e0053521 [View Article] [PubMed]
     [Google Scholar]
  62. wgsim; 2011 https://github.com/lh3/wgsim accessed 1 August 2022
  63. Li H, Durbin R. Fast and accurate short read alignment with burrows-wheeler transform. Bioinformatics 2009; 25:1754–1760 [View Article] [PubMed]
     [Google Scholar]
  64. Quick J, Ashton P, Calus S, Chatt C, Gossain S et al. Rapid draft sequencing and real-time nanopore sequencing in a hospital outbreak of Salmonella. Genome Biol 2015; 16:114 [View Article] [PubMed]
     [Google Scholar]
  65. Nguyen L-T, Schmidt HA, von Haeseler A, Minh BQ. IQ-TREE: a fast and effective stochastic algorithm for estimating maximum-likelihood phylogenies. Mol Biol Evol 2015; 32:268–274 [View Article] [PubMed]
     [Google Scholar]
  66. Stamatakis A. RAxML version 8: a tool for phylogenetic analysis and post-analysis of large phylogenies. Bioinformatics 2014; 30:1312–1313 [View Article] [PubMed]
     [Google Scholar]
  67. Mostowy S, Inwald J, Gordon S, Martin C, Warren R et al. Revisiting the evolution of Mycobacterium bovis. J Bacteriol 2005; 187:6386–6395 [View Article] [PubMed]
     [Google Scholar]
  68. Angelidou A, Diray-Arce J, Conti MG, Smolen KK, van Haren SD et al. BCG as a case study for precision vaccine development: lessons from vaccine heterogeneity, trained immunity, and immune ontogeny. Front Microbiol 2020; 11:332 [View Article] [PubMed]
     [Google Scholar]
  69. Dubos RJ, Pierce CH. Differential characteristics in vitro and in vivo of several Substrains of Bcg1. Am Rev Tuberculosis Pulmon Dis 1956; 74:655–666
     [Google Scholar]
  70. Panaiotov S, Hodzhev Y, Tolchkov V, Tsafarova B, Mihailov A et al. Complete genome sequence, genome stability and phylogeny of the vaccine strain Mycobacterium bovis BCG SL222 Sofia. Vaccines 2021; 9:1–10 [View Article] [PubMed]
     [Google Scholar]
  71. Ru H, Liu X, Lin C, Yang J, Chen F et al. The impact of genome region of difference 4 (RD4) on Mycobacterial virulence and BCG efficacy. Front Cell Infect Microbiol 2017; 7:239 [View Article] [PubMed]
     [Google Scholar]
  72. Yuan C-H, Zhang S, Xiang F, Gong H, Wang Q et al. Secreted Rv1768 From RD14 of Mycobacterium tuberculosis activates macrophages and induces a strong IFN-γ-releasing of CD4+ T cells. Front Cell Infect Microbiol 2019; 9:341 [View Article] [PubMed]
     [Google Scholar]
  73. Mostowy S, Onipede A, Gagneux S, Niemann S, Kremer K et al. Genomic analysis distinguishes Mycobacterium africanum. J Clin Microbiol 2004; 42:3594–3599 [View Article] [PubMed]
     [Google Scholar]
  74. Marmiesse M, Brodin P, Buchrieser C, Gutierrez C, Simoes N et al. Macro-array and bioinformatic analyses reveal mycobacterial “core” genes, variation in the ESAT-6 gene family and new phylogenetic markers for the Mycobacterium tuberculosis complex. Microbiology 2004; 150:483–496 [View Article] [PubMed]
     [Google Scholar]
  75. Bigi F, Garcia-Pelayo MC, Nuñez-García J, Peralta A, Caimi KC et al. Identification of genetic markers for Mycobacterium pinnipedii through genome analysis. FEMS Microbiol Lett 2005; 248:147–152 [View Article] [PubMed]
     [Google Scholar]
  76. Tsolaki AG, Hirsh AE, DeRiemer K, Enciso JA, Wong MZ et al. Functional and evolutionary genomics of Mycobacterium tuberculosis: insights from genomic deletions in 100 strains. Proc Natl Acad Sci 2004; 101:4865–4870 [View Article] [PubMed]
     [Google Scholar]
  77. Kato-Maeda M, Rhee JT, Gingeras TR, Salamon H, Drenkow J et al. Comparing genomes within the species Mycobacterium tuberculosis. Genome Res 2001; 11:547–554 [View Article] [PubMed]
     [Google Scholar]
  78. Brosch R, Gordon SV, Garnier T, Eiglmeier K, Frigui W et al. Genome plasticity of BCG and impact on vaccine efficacy. Proc Natl Acad Sci U S A 2007; 104:5596–5601 [View Article] [PubMed]
     [Google Scholar]
  79. Corrales RM, Molle V, Leiba J, Mourey L, de Chastellier C et al. Phosphorylation of Mycobacterial PcaA inhibits mycolic acid cyclopropanation: consequences for intracellular survival and for phagosome maturation block. J Biol Chem 2012; 287:26187–26199 [View Article] [PubMed]
     [Google Scholar]
  80. Behr MA. BCG--different strains, different vaccines?. Lancet Infect Dis 2002; 2:86–92 [View Article] [PubMed]
     [Google Scholar]
  81. Belley A, Alexander D, Di Pietrantonio T, Girard M, Jones J et al. Impact of methoxymycolic acid production by Mycobacterium bovis BCG vaccines. Infect Immun 2004; 72:2803–2809 [View Article] [PubMed]
     [Google Scholar]
  82. Veyrier F, Saïd-Salim B, Behr MA. Evolution of the Mycobacterial SigK regulon. J Bacteriol 2008; 190:1891–1899 [View Article] [PubMed]
     [Google Scholar]
  83. Matsumoto S, Matsuo T, Ohara N, Hotokezaka H, Naito M et al. Cloning and sequencing of a unique antigen MPT70 from Mycobacterium tuberculosis H37Rv and expression in BCG using E. coli-mycobacteria shuttle vector. Scand J Immunol 1995; 41:281–287 [View Article] [PubMed]
     [Google Scholar]
  84. Mustafa AS. Comparative evaluation of MPT83 (Rv2873) for T helper-1 cell reactivity and identification of HLA-promiscuous peptides in Mycobacterium bovis BCG-vaccinated healthy subjects. Clin Vaccine Immunol 2011; 18:1752–1759 [View Article] [PubMed]
     [Google Scholar]
  85. Di Luca M, Bottai D, Batoni G, Orgeur M, Aulicino A et al. The ESX-5 associated eccB-EccC locus is essential for Mycobacterium tuberculosis viability. PLoS One 2012; 7:e52059 [View Article] [PubMed]
     [Google Scholar]
  86. Ates LS, Ummels R, Commandeur S, van de Weerd R, Sparrius M et al. Essential role of the ESX-5 secretion system in outer membrane permeability of pathogenic Mycobacteria. PLoS Genet 2015; 11:1–30 [View Article] [PubMed]
     [Google Scholar]
  87. Abdallah AM, Gey van Pittius NC, Champion PAD, Cox J, Luirink J et al. Type VII secretion--Mycobacteria show the way. Nat Rev Microbiol 2007; 5:883–891 [View Article] [PubMed]
     [Google Scholar]
  88. Tiwari S, Dutt TS, Chen B, Chen M, Kim J et al. BCG-Prime and boost with Esx-5 secretion system deletion mutant leads to better protection against clinical strains of Mycobacterium tuberculosis. Vaccine 2020; 38:7156–7165 [View Article] [PubMed]
     [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/mgen/10.1099/mgen.0.001077
Loading
Mapping the phylogeny and lineage history of geographically distinct BCG vaccine strains
M Gen 9, 001077 (2023); https://doi.org/10.1099/mgen.0.001077
/content/journal/mgen/10.1099/mgen.0.001077
/content/journal/mgen/10.1099/mgen.0.001077
Loading

Data & Media loading...

Supplements

Supplementary material 1

PDF

Most cited Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error