Dynamic tracking analysis of monoclonal antibodies (mAbs) biotransformation in vivo is crucial, as certain modifications could inactivate the protein and reduce drug efficacy. However, a particular challenge (i.e. immune recognition deficiencies) in biotransformation studies may arise when modifications occur at the paratope recognized by the antigen. To address this limitation, a multi-epitope affinity technology utilizing the metal organic framework (MOF)@Au@peptide@aptamer composite material was proposed and developed by simultaneously immobilizing complementarity determining region (CDR) mimotope peptide (HH24) and non-CDR mimotope aptamer (CH1S-6T) onto the surface of MOF@Au nanocomposite. Comparative studies demonstrated that MOF@Au@peptide@aptamer exhibited significantly enhanced enrichment capabilities for trastuzumab variants in comparison to mono-epitope affinity technology. Moreover, the higher deamidation ratio for LC-Asn-30 and isomerization ratio for HC-Asn-55 can only be monitored by the novel bioanalytical platform based on MOF@Au@peptide@aptamer and liquid chromatography-quadrupole time of flight-mass spectrometry (LC-QTOF-MS). Therefore, multi-epitope affinity technology could effectively overcome the biases of traditional affinity materials for key sites modification analysis of mAb. Particularly, the novel bioanalytical platform can be successfully used for the tracking analysis of trastuzumab modifications in different biological fluids. Compared to the spiked phosphate buffer (PB) model, faster modification trends were monitored in the spiked serum and patients' sera due to the catalytic effect of plasma proteins and relevant proteases. Differences in peptide modification levels of trastuzumab in patients' sera were also monitored. In summary, the novel bioanalytical platform based on the multi-epitope affinity technology holds great potentials for in vivo biotransformation analysis of mAb, contributing to improved understanding and paving the way for future research and clinical applications.

Objective To explore the application value of cone-shaped gastric tube combined with cervical end-to-end anastomosis in thoracoscopic and laparoscopic esophagectomy for esophageal cancer.Methods The retrospective and descriptive study was conducted.The clinical data of 122 patients with esophageal cancer who were admitted to West China Hospital of Sichuan University from December 2016 to December 2017 were collected.There were 89 males and 33 females,aged (61±8)years,with a range from 48 to 81 years.McKeowntype three-incision esophagectomy was performed,and the cone-shaped gastric tube was pulled up to esophagus in left neck for hand-sewn end-to-end anastomosis after the dissection of esophagus and stomach under total thoracoscopy and laparoscopy.Observation indicators:(1) surgical treatment situations;(2) postoperative complications;(3) follow-up.Follow-up using outpatient examination was performed to detect postoperative gastroesophageal reflux,anastomotic stenosis and evaluate anastomotic width at 1,3,6 months and one year postoperatively up to December 2018.Measurement data with normal distribution were represented by Mean±SD.Measurement data with skewed distribution were described by M (P25,P75) or M (range).Count data were expressed by absolute number.Results (1) Surgical treatment situations:122 patients underwent laparocopic McKeown-type three-incision esophagectomy successfully,using cone-shaped gastric tube combined with cervical hand-sewn end-to-end anastomosis as digestive tract reconstruction,with no intraoperative conversion to open surgery.The operation time,cervical anastomosis time,and volume of intraoperative blood loss were (229 ± 49) minutes,(27± 1) minutes,and 50 mL (40 mL,60 mL),respectively.There were 6-8 stations of lymph node dissected,and the number of lymph node dissected were 19 (15,25).Duration of postoperative hospital stay was 10 days (9 days,11 days) in the 122 patients.(2) Postoperative complications:31 of 122 patients had postoperative complications.The primary complications:3 patients with anastomotic fistula were cured by conservative treatment including enteral nutrition through placement of nutritional tube under gastroscope,closed thoracic drainage and anti-infection;6 cases with severe thoracic gastric dilation were cured after gastrointestinal decompression.The secondary complications of 22 patients included 8 cases with hoarseness caused by recurrent laryngeal never injury,5 with arrhythmia,9 with pulmonary infection.They were cured after symptomatic and supportive treatment.No chylothorax occured,and there was no perioperative death.(3) Follow-up:all the 122 patients were followed up for 10-24 months,with a median time of 19 months.During the follow-up,7 cases with anastomotic stenosis including 4 scoring less than grade 2 and 3 scoring more than grade 3 were relieved after dilation through gastroscope.There were 33 of 122 patients without any reflux symptoms,and 89 with reflux symptoms,among which 52 were scored 1,25 were scored 2 and 12 were scored 3.The width of gastroesophageal anastomosis measured by barium radiography at 1 month after operation was (1.2±0.4) cm.Conclusion Coneshaped gastric tube combined with cervical end-to-end anastomosis in digestive tract reconstruction of thoracoscopic and laparoscopic esophagectomy can reduce the incidence of postoperative anastomotic complications and thoracic gastric dilation,and nasogastric tube placement could be abandoned,which demonstrates good safety and universality.