Objective: To characterize the primary structure of the active national standard candidate of infliximab to provide a technical basis for this monoclonal antibody. Methods: The complete relative molecular mass and the relative molecular masses of the light and heavy chain subunits of the active national standard candidate of infliximab were detected based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS). The relative molecular masses of the light and heavy chain subunits of the active national standard candidate of infliximab were analyzed by UPLC-MS/MS. UPLC-MS/MS was used to analyze the sequence coverage,glycosylation sites and disulfide bond localization of infliximab activity candidate national standard products. Results: The complete relative molecular mass of infliximab was 148 515. The relative masses of its light and heavy chain subunits were 23 435 and 50 827 respectively. The sequence coverage of infliximab was 100% for light chain and 100% for heavy chain. The glycosylation sites of infliximab were analyzed by UPLC-MS/MS; and the disulfide bonds were localized. The glycosylation site of the monoclonal antibody candidate was located at N300 of the heavy chain; there were 16 pairs of disulfide bonds, 4 pairs within each of the two heavy chains, 2 pairs between chains,2 pairs within each of the 2 light chains, and 1 pair between each of the two groups of light and heavy chains. Conclusion: The primary structural confirmation of the national standard candidate of infliximab monoclonal antibody activity provides a technical guarantee for the establishment of the monoclonal antibody standard substance, the standardization of analytical methods and the control of product quality.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |