Lipid phenotype of two distinct subpopulations of Mycobacterium bovis Bacillus Calmette-Guerin Tokyo 172 substrain.
Bacillus Calmette-Guérin (BCG) Tokyo 172 is a predominant World Health Organization Reference Reagent for the BCG vaccine. Recently, the BCG Tokyo 172 substrain was reported to consist of two subpopulations with different colony morphologies, smooth and rough. Smooth colonies had a characteristic 22-bp deletion in Rv3405c of the region of difference (RD) 16 (type I), and rough colonies were complete in this region (type II). We hypothesized that the morphological difference is related to lipid phenotype and affects their antigenicity. We determined the lipid compositions and biosynthesis of types I and II. Scanning electron microscopy showed that type I was 1.5 times longer than type II. Phenolic glycolipid (PGL) and phthiocerol dimycocerosate (PDIM) were found only in type I. Although it has been reported that the RD16 is involved in the expression of PGL, type II did not possess PGL/PDIM. We examined the ppsA-E gene responsible for PGL/PDIM biosynthesis and found that the existence of PGL/PDIM in types I and II is caused by a ppsA gene mutation not regulated by the RD16. PGL suppressed the host recognition of total lipids via Toll-like receptor 2, and this suggests that PGL is antigenic and involved in host responses, acting as a cell wall component. This is the first report to show the difference between lipid phenotypes of types I and II. It is important to clarify the heterogeneity of BCG vaccine substrains to discuss and evaluate the quality, safety, and efficacy of the BCG vaccine.
Department of Bacteriology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan; MBR Co. Ltd., Osaka 560-8552, Japan.
Takashi
T
Naka
Molecular Epidemiology Division, Mycobacterium Reference Center, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo 204-8533, Japan.
Shinji
S
Maeda
Department of Bacteriology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan.
Mamiko
M
Niki
Department of Oral Microbiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan.
Naoya
N
Ohara
Japan BCG Laboratory, Tokyo 204-0022, Japan.
Saburo
S
Yamamoto
Japan BCG Laboratory, Tokyo 204-0022, Japan.
Ikuya
I
Yano
Department of Safety Research on Blood and Biological Products, National Institute of Infectious Diseases, Tokyo 208-0011, Japan.
Jun-Ichi
JI
Maeyama
Department of Bacteriology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan; Department of Virology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan.
Hisashi
H
Ogura
Department of Immunology, National Institute of Infectious Diseases, Tokyo 208-0011, Japan.
Kazuo
K
Kobayashi
Department of Bacteriology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan. Electronic address: fujiwara@med.osaka-cu.ac.jp.
Nagatoshi
N
Fujiwara
D000818:Animals; D001500:BCG Vaccine / Q000378:metabolism*; D002241:Carbohydrates / Q000737:chemistry; D002855:Chromatography, Thin Layer / Q000379:methods; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics; D005227:Fatty Acids / Q000378:metabolism; D005838:Genotype; D006017:Glycolipids / Q000737:chemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D009163:Mycobacterium bovis / Q000235:genetics* / Q000276:immunology; D009171:Mycolic Acids / Q000378:metabolism; D010641:Phenotype; D050743:Pyruvate Synthase / Q000235:genetics
D001500:BCG Vaccine; D002241:Carbohydrates; D029968:Escherichia coli Proteins; D005227:Fatty Acids; D006017:Glycolipids; D009171:Mycolic Acids; D050743:Pyruvate Synthase; C506224:ppsA protein, E coli