Purification of HC1·TSG-6 complex. Pool 1, containing the
HC1·TSG-6 complex, from the strong cation exchange-HPLC analysis was
subjected to RP-HPLC analysis directly (A) or after treatment with
NaOH (B). The asterisk-labeled peaks contained
MH+ of m/z 1424.59 and m/z
2241.15, respectively. C, MALDI-TOF MS analysis of peak α from
RP-HPLC of the untreated pool 1. The analysis shows that the peak contains the
HC1·TSG-6 complex (theoretical monoisotopic MH+:
m/z 2174.04). D, MALDI-TOF MS analysis of peak
β from RP-HPLC of the NaOH-treated pool 1. The analysis shows that the
peak contains the tryptic TSG-6 peptide
(22DGIFHNSIWLER33, theoretical monoisotopic
MH+: m/z 1486.73), that participates in the
cross-link. The analyses demonstrate that HC1·TSG-6
(632VTGVDTD638 cross-linked to
22DGIFHNSIWLER33) has been purified and is present in
peak α.