Jos Jansen

116 Chapter 5 Results A total of 1042 samples were collected, 567 samples of LTx candidates and 475 samples of patients with CLD. Figure 2 shows a flowchart of the study design. We included 981 samples for further N-glycan analysis with tIEF. After tIEF, 744 samples including 20 samples with a confirmed polymorphism were excluded based on a normal profile Subsequently, QTOF-MS was performed on 247 samples and 40 healthy controls. After QTOF-MS analysis, 125 samples were excluded because the main peak (at 79556 amu) was of insufficient abundance, 10 samples were excluded because of an abnormal glycation profile and 3 because of a TF polymorphism (of which 2 were not identified with tIEF and one was a healthy control). In total, 110 patient samples and 39 healthy control samples were of sufficient quality for interpretation of the glycosylation profile. Table 1 shows patient characteristics for the selected samples. Supplementary table 1 shows tIEF and QTOF-MS results for all samples with an abnormal tIEF profile. tIEF screening of 961 samples of liver disease patients showsmild glycosylation abnormalities Out of 961 sampleswe analyzedusing tIEF, 247 samples (26%) hadhyposialylation compared to our controls. Of these samples, 175 (70%) had a solitary increased percentage of the trisialoTF isoform, 42 (17%) had an elevated percentage of monosialoTF isoform and 4 (2%) had an elevated percentage of the disialoTF isoform. Mixed combinations of elevated isoforms occurred in 26 (11%) samples. (Figure 3a) None of the samples had increased percentages of all isoforms. One sample had slightly increased percentages of the asialo and the disialoTF isoform and did not reach the values to be suggestive for type 1 CDG. The mixed profiles can be compatible with a CDG type 2 profile, however, in most samples the increase in percentage is subtle (Figure 3b).