Objective: To establish a method of collecting transplantation major histocompatibility complex (MHC) peptides.
Methods: Splenic cells of C57BL/6 donor mice were injected into BALB/c recipient mice. The splenic cells of the recipient mice were soaked in pH3.3 citric acid buffer to wash off the MHC conjugated peptides. Peptide contents and components in the elutriant were detected by BCA protein assay and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Antigenicity of the peptides was verified by murine heterotopic heart transplantation.
Results: Fifty micro-gram mixed peptides (including short peptides) per 10(8) cells were collected by the elution method. HPLC-MS/MS revealed that there were differences in peptide components between allo-transplantation group and control group. Medial survival time of heart grafts of same strain MHC peptide pre-immunization group was 8 days, and that of allo-MHC peptide pre-immunization group was 4 days. Medial survival time of heart grafts was shortened significantly by pre-immunization with allo-MHC peptides.
Conclusion: Transplantation MHC peptides can be obtained by donor splenic cell immunization and elution from recipients' splenic cells with mild acid. They can be used for screening transplantation antigenic determinants.