Expression And In Vitro Function Identification Of Anti-human CCL22 And CCL17 Immunotoxins

Objective:Using yeast Pichia Pastoris strain to express and purify both of the monovalent and bivalent of recombinant Anti-human-CCL22 and Anti-human-CCL17 immunotoxins, and assess their in vitro function potency.Methods:All immunotoxins were expressed by a specific modified diphtheria toxin resistant yeast strain called:Pichia Pastoris, then the synthetic protein will go through a two-step purification includes Ni-Sepharose 6 Fast flow column purification and Poros 50 HQ Strong Anion Exchange column purification, after purification, the purified product will be analyzed by both SDS-PAGE and Western Blot; concentration of immunotoxins will be detected by BCA assay; Then all 4 immunotoxins (including both of the monovalent and bivalent of recombinant Anti-human-CCL22 and Anti-human-CCL17 immunotoxins) were labeled with NHS-Sulfo biotin which later could be used as a convenient way to analyze the Binding Affinity of all 4 immunotoxins toward CCRP-CEM tumor cell line; Protein synthesis inhibition assay using 3H Isotope was performed to determine the in vitro functional potency of both Anti-human-CCL22 and Anti-human-CCL17 immunotoxins, also, Luminescent Cell Viability Assay was performed to determine the in vitro depletion potency of all 4 immunotoxins.Results:According to the results of SDS-PAGE and Western Blot, all 4 immunotoxins were successfully expressed and purified, and all of them can be bound to CCRP-CEM tumor cell line; both Anti-human CCL22 monovalent immunotoxin and Anti-human CCL17 monovalent immunotoxin possess the ability of inhibit protein synthesis of CCRF-CEM tumor cell line; Assessed by the Luminescent Cell Viability Assay, all 4 immunotoxins is proved to be functional of inhibit the cell viability of CCRF-CEM tumor cell line, plus a significant difference showed that bivalent seems to have a better binding and functional ability than monovalent version.Conclusion:All 4 immunotoxins (including both of the monovalent and bivalent of recombinant Anti-human-CCL22 and Anti-human-CCL17 immunotoxins) were successfully expressed and purified, an ability of binding and proliferation inhibition was proved towards CCRP-CEM tumor cell line for 4 immunotoxins, which hopefully can contribute to further clinical researches and studies.