Journal: eLife

Article Title: Targeted computational design of an interleukin-7 superkine with enhanced folding efficiency and immunotherapeutic efficacy

doi: 10.7554/eLife.107671

Figure Lengend Snippet: In general, non-receptor interacting loops were deleted from the WT-IL7 sequence and loops connecting the adjacent helices were modeled using Rosetta Loop Remodeler and Rosetta fix backbone design function. The sequence of the designed model was extracted and submitted to AlphaFold (monomer and multimer mode for structure and protein-receptor binding prediction respectively) as a preliminary validation of the Rosetta-remodeled protein. Iterations of the bad models (models that do not fold into the expected structure or models that did not predict to bind to the receptors) back to the design stage were performed. Models that passed the AlphaFold validation proceeded to subsequent in vitro assay using yeast display system and flow cytometry to determine their relative binding affinity to IL-7 receptors in comparison to WT-IL7.

Article Snippet: Receptor binding was done by incubation of yeast with a final concentration of 50 nM IL-7 receptor-α (IL7Rα; Sino Biological Cat: 50090-M08H) consisting of a C-terminal polyhistidine tag for 30 min at 4°C on a mini shaker agitated at 600 rpm.

Techniques: Sequencing, Binding Assay, Biomarker Discovery, In Vitro, Flow Cytometry, Comparison

Journal: eLife

Article Title: Targeted computational design of an interleukin-7 superkine with enhanced folding efficiency and immunotherapeutic efficacy

doi: 10.7554/eLife.107671

Figure Lengend Snippet: Blueprint of the WT-IL7 was shown on the left of the figure. The connectivity of the functioning helixes was connected in a manner that requires extremely long protein loops by design (i.e. helices were not connected to the closest adjacent helixes but to the opposite helix). Loops that were not interacted with the IL-7 receptors were deleted and the helixes were reconnected in a clockwise manner via new protein linkers connecting to the adjacent helixes. The blueprint of the redesigned protein was shown at the right side of the figure. Protein structures are colored as rainbow (from N-to-C terminus with the order of Blue-Green-Yellow-Red).

Article Snippet: Receptor binding was done by incubation of yeast with a final concentration of 50 nM IL-7 receptor-α (IL7Rα; Sino Biological Cat: 50090-M08H) consisting of a C-terminal polyhistidine tag for 30 min at 4°C on a mini shaker agitated at 600 rpm.

Techniques:

Journal: eLife

Article Title: Targeted computational design of an interleukin-7 superkine with enhanced folding efficiency and immunotherapeutic efficacy

doi: 10.7554/eLife.107671

Figure Lengend Snippet: ( A ) AlphaFold validation of the first loop design version of Neo-7 (Neo-7 LDv1) using the default (left) and single sequence mode (right). ( B ) AlphaFold validation of the second loop design version of Neo-7 (left; Neo-7 LDv2) and Neo-7 LDv2 with mutations (right) favored by Rosetta fix backbone design. ( C ) Crystal structure of human IL-7 in complexation to human IL-7 receptor alpha (PDB ID = 3DI2). ( D ) Superimposition of Neo-7 structures (with or without additional disulfide bridge) predicted by AlphaFold. ( E ) Yeast display and flow cytometry validation of IL-7/Neo-7 bindings towards the IL-7 receptors. The yeast-displayed protein (different redesigned IL-7s) carries a HA-tag while the recombinant IL-7 receptors carry either a HIS tag (IL-7 receptor alpha) or a FC-tag (common-IL-2 family receptor gamma; for detection of IL-2Rγ binding, yeast cells were first incubated with recombinant IL-7Rα, washed, and subsequently incubated with IL-2Rγ.) The signal intensity of the X-axis (conferred by the binding of anti-HA mab) correlates with the expression level of the displayed protein while the signal intensity of the Y-axis (conferred by the binding of the anti-HIS/anti-FC mAb to the recombinant receptors bound to the displayed proteins) correlates with the binding affinity of the displayed proteins towards the IL-7 receptors.

Article Snippet: Receptor binding was done by incubation of yeast with a final concentration of 50 nM IL-7 receptor-α (IL7Rα; Sino Biological Cat: 50090-M08H) consisting of a C-terminal polyhistidine tag for 30 min at 4°C on a mini shaker agitated at 600 rpm.

Techniques: Biomarker Discovery, Sequencing, Flow Cytometry, Recombinant, Binding Assay, Incubation, Expressing

Journal: eLife

Article Title: Targeted computational design of an interleukin-7 superkine with enhanced folding efficiency and immunotherapeutic efficacy

doi: 10.7554/eLife.107671

Figure Lengend Snippet: ( A ) Inspection of structural and binding interactions of residue mutations Q6P and T45I on Neo-7 towards the murine IL-7R alpha. ( B ) Yeast display and flow cytometry validation of the binding ability of IL-7/Neo-7 variants toward the IL-7 receptors.

Article Snippet: Receptor binding was done by incubation of yeast with a final concentration of 50 nM IL-7 receptor-α (IL7Rα; Sino Biological Cat: 50090-M08H) consisting of a C-terminal polyhistidine tag for 30 min at 4°C on a mini shaker agitated at 600 rpm.

Techniques: Binding Assay, Residue, Flow Cytometry, Biomarker Discovery

Journal: eLife

Article Title: Targeted computational design of an interleukin-7 superkine with enhanced folding efficiency and immunotherapeutic efficacy

doi: 10.7554/eLife.107671

Figure Lengend Snippet: FPLC profile of E. coli expressed ( A ) WT-IL7 ( B ) refolded WT-IL7 ( C ) Neo-7-Q6P and ( D ) Neo-7-Q6P-T45I. Percentage of purity is calculated from the SEC-FPLC peak profile via Cytiva Unicorn 7 software after affinity chromatography purification. SPR (Biacore) characterization of the binding kinetics of ( E ) Neo-7-Q6P ( F ) Neo-7-Q6P-T45I and ( G ) WT-IL7 towards murine IL-7R alpha. ( H ) 2E8 proliferation assay to investigate the biological activity of the IL-7/Neo-7s expressed by E. coli . Error bars represent standard deviation (n=3).

Article Snippet: Receptor binding was done by incubation of yeast with a final concentration of 50 nM IL-7 receptor-α (IL7Rα; Sino Biological Cat: 50090-M08H) consisting of a C-terminal polyhistidine tag for 30 min at 4°C on a mini shaker agitated at 600 rpm.

Techniques: Software, Affinity Chromatography, Purification, Binding Assay, Proliferation Assay, Activity Assay, Standard Deviation