Recombinant antibodies were purified from culture supernatants derived from the Dictyostelium discoideum model and loaded into an SDS-PAGE electrophoresis gel. The electrophoretic profile of the anti-alpha tubulin, anti-CISD1, and anti-CD8β antibodies reveals a band at 35 kDa, likely corresponding to a degradation product of the recombinant antibody. Additionally, a non-specific band appears under all conditions at 170 kDa. The objective of this analysis was to characterize these bands by mass spectrometry.