Table 1.
Molecular biological approaches developed to aid in the serotyping of S. suis.
| Method | Detecting Serotypes and Descriptions a | Year | Reference |
|---|---|---|---|
| PCR (3 assays) | Assay 1: Serotypes 1 and 14; | 1999 | [49] |
| Assay 2: Serotypes 2 and 1/2; | |||
| Assay 3: Serotype 9 | |||
| PCR | Serotype 7 | 1999 | [50] |
| Multiplex-PCR | Serotypes 1, 2, 1/2, 7, 9, and 14 | 2002 | [51] |
| epf (a virulence-associated marker of S. suis) is also detected | |||
| Multiplex-PCR | Serotypes 2 and 1/2 | 2004 | [52] |
| S. suis-specific sequence of the 16S rRNA gene is also detected | |||
| Multiplex-PCR | Serotypes 1, 2, 1/2, 7, 9, and 14 | 2006 | [53] |
| epf, sly, mrp, arcA (virulence-associated markers of S. suis), and S. suis-specific sequence of gdh are also detected | |||
| PCR | Serotype 16 | 2011 | [54] |
| Real-time PCR | Serotypes 2 and 1/2 | 2011 | [55] |
| PCR (8 assays) | Assay 1: Serotype 3; Assay 2: Serotype 4; | 2012 | [56] |
| Assay 3: Serotype 5; Assay 4: Serotype 8; | |||
| Assay 5: Serotype 10; Assay 6: Serotype 19; | |||
| Assay 7: Serotype 23; Assay 8: Serotype 25; | |||
| Multiplex-PCR (2 reaction sets) | 15 serotypes (serotypes 1−5, 7−10, 14, 16, 19, 23, 25, and 1/2) | 2012 | [57] |
| Reaction 1: Serotypes 1, 2, 1/2, 3, 4, 7, 9, 14, and 16 | |||
| Reaction 2: Serotypes 5, 8, 10, 19, 23, and 25 | |||
| In both reactions, the S. suis-specific sequence of the gdh gene is also detected | |||
| Multiplex-PCR (4 reaction sets) | 33 serotypes (serotypes 1−31, 33, and 1/2) and variant serotype 21/29 | 2013 | [15] |
| Reaction 1: Serotypes 1−10, 14, and 1/2 | |||
| Reaction 2: Serotypes 11−21 | |||
| Reaction 3: Serotypes 22−33 | |||
| Reaction 4: Serotype 21/29 | |||
| In all reactions, the S. suis-specific sequence of the thrA gene is also detected | |||
| LAMP | Serotypes 2 and 1/2 | 2013 | [58] |
| Multiplex-PCR (2-step assay) | 35 serotypes (serotypes 1−34 and 1/2) | 2014 | [48] |
| Step 1: classified into 7 groups (Group I−VII) | |||
| Group I: serotypes 3, 13, and 18 | |||
| Group II: serotypes 1, 2, 1/2, 6, 14, 16, and 27 | |||
| Group III: serotypes 21, 28, 29, and 30 | |||
| Group IV: serotypes 4, 5, 7, 17, 19, and 23 | |||
| Group V: serotypes 8, 15, 20, 22, and 25 | |||
| Group VI: serotypes 9, 10, 11, 12, 24, 26, and 33 | |||
| Group VII: serotypes 31, 32, and 34 | |||
| Step 2: classified into respective serotypes of each group | |||
| In all reactions, universally shared sequences of the 16S rRNA gene are also detected | |||
| Multiplex-PCR (4 reaction sets) | 29 serotypes (serotypes 1−19, 21, 23−25, 27−31, 33, and 1/2) | 2014 | [59] |
| Reaction 1: Serotypes 1, 2, 1/2, 3, 7, 9, 11, 14, and 16 | |||
| Reaction 2: Serotypes 4, 5, 8, 12, 18, 19, 24, and 25 | |||
| Reaction 3: Serotypes 6, 10, 13, 15, 17, 23, and 31 | |||
| Reaction 4: Serotypes 21, 27, 28, 29, and 30 | |||
| In all reactions, the S. suis-specific sequence of the gdh gene is also detected | |||
| PCR | Serotype Chz | 2015 | [14] |
| luminex xTAG® assay™ | 33 serotypes (serotypes 1−31, 33, and 1/2) | 2015 | [60] |
a. epf, encoding an extracellular factor; sly, encoding suilysin; mrp, encoding muramidase-released protein; arcA, encoding arginine deiminase; gdh, encoding glutamate dehydrogenase; thrA, encoding aspartokinase/homoserine dehydrogenase I; LAMP, loop-mediated isothermal amplification.