We previously demonstrated that a protein's immunogenicity could be substantially increased by attaching a hydrophobic solubility controlling peptide tag (SCP-tag) producing small sub-visible aggregates. Here, we report the oligomerization of Dengue envelop protein domain 3 (ED3), and consequently, its immunogenicity increase by mixing ED3s attached with SCP-tags of opposite charges at equimolar concentration. We used ED3 of serotype 3 (D3ED3) and serotype 4 (D4ED3), which are, respectively, moderately and poorly immunogenic, and their SCP tagged variants constructed by attaching either a C-termini 5-Aspartic acid (C5D) or a 5-Lysine (C5K) tag.
View Article and Find Full Text PDFPoor immunogenicity of small proteins is a major hurdle in developing vaccines or producing antibodies for biopharmaceutical usage. Here, we systematically analyzed the effects of 10 solubility controlling peptide tags (SCP-tags) on the immunogenicity of a non-immunogenic model protein, bovine pancreatic trypsin inhibitor (BPTI-19A; 6 kDa). CD, fluorescence, DLS, SLS, and AUC measurements indicated that the SCP-tags did not change the secondary structure content nor the tertiary structures of the protein nor its monomeric state.
View Article and Find Full Text PDFAmorphous aggregates of therapeutic proteins can provoke an unwanted immune response (anti-drug antibodies; ADAs), but counter-examples have led to some controversy. Amorphous aggregates can possess unique biophysical and biochemical attributes depending on both the way they are generated and the protein's biophysical/biochemical properties. Here, we examine the immunogenicity of an anti-EGFR single domain antibody (V) in four types of amorphous aggregates: two heat-aggregated V incubated at 65 °C (V-65) and 95 °C (V-95), a misfolded V isolated from the insoluble fraction of the E.
View Article and Find Full Text PDFRecombinant proteins are an attractive choice as a safe alternative to traditional live attenuated vaccines. However, most small-size proteins are poorly immunogenic, and adjuvants, whose mode of action remain to be fully clarified, are needed for increasing their immunogenicity. Here, we report the effects of short solubility controlling peptide tags (SCP-tags) on the immunogenicity of DENV3 envelope protein domain 3 (3ED3; 103 residues, 11.
View Article and Find Full Text PDFSubvisible aggregates of proteins are suspected to cause adverse immune response, and a recent FDA guideline has recommended the monitoring of micrometer-sized aggregates (2-10 μm) though recognizing that the underlying mechanism behind aggregation and immunogenicity remains unclear. Here, we report a correlation between the immunogenicity and the size of nanometer-scaled aggregates of a small 6.5 kDa model protein, bovine pancreatic trypsin inhibitor (BPTI) variant.
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