Agonist Target Proteins to Accelerate Immunotherapy Development

Derived from the Nobel Prize-winning work of Dr. James P. Allison and  Dr. Tasuku Honjo, immune checkpoint proteins were identified to be the key regulators of the immune system. However, current approved drugs are checkpoint inhibitors. This means that these drugs are meant to prevent an ‘OFF’ signal from reaching the immune system. But what if the immune response just isn’t enough?

Agonists, otherwise called stimulatory checkpoint molecules, are here to ‘hit the gas’ or accelerate your immune response. Rather than inhibiting the ‘OFF’signal, the key of this target is to constantly give a green light to maximize the immune response.  This means utilizing multiple costimulatory to activate T cells. For example, B7-CD28 signaling is a major costimulatory signaling cascade contributing to T-cell activation and cytokine release. 4-1BB, OX40, glucocorticoid-induced tumor necrosis factor (TNF) receptor (GITR) and other receptors in the TNF superfamily can synergize with TCR signaling to enhance T-cell responses and survival. As such, agonists of co-stimulatory receptors of the tumor necrosis factor superfamily (TNF-SF) and B7 family are emerging as promising options to expand the immunomodulatory toolbox.

ACROBiosystems has developed a series of products targeting immune co-stimulatory molecules of TNFSF and B7-CD28 family, including proteins, overexpression cell lines, and inhibitor screening kits. All products are verified and validated, not only as a final product, but starting from antibody preparation, initial screening, production to quality control; ensuring the best reagents and tools to develop your agonist immunotherapies.

Authentic polymer structure and purity verified by SEC-MALS

The purity of Human OX40 Ligand, His Tag (active trimer) (Cat. No. OXL-H52Q8 ) is more than 95% in HP-SEC, and the molecular weight of this protein is around 60-80 kDa verified by SEC-MALS.

The purity of Human / Cynomolgus / Rhesus macaque CD28 Protein, His Tag (Cat. No. CD8-H52H3) is more than 90% and the molecular weight of this protein is around 65-75 kDa verified by SEC-MALS.

Validation of high bioactivity of binding with receptor or antibody

Immobilized Human 4-1BB, His Tag (Cat. No. 41B-H52Hc) at 1 μg/mL (100 μL/well) can bind Utomilumab with a linear range of 0.1-4 ng/mL (Routinely tested).

Protocol

Human UreluMab captured on CM5 chip via Anti-human IgG Fc antibodies surface can bind Human 4-1BB, His Tag (Cat. No. 41B-H52Hc) with an affinity constant of 3.59 nM as determined in a SPR assay (Biacore 8K) (Routinely tested)

Protocol

FACS assay shows that Monoclonal UreluMab antibody, Human IgG4 can bind to HEK293/Human 4-1BB / TNFRSF9 Stable Cell Line (CHEK-ATP038). HEK293/Human 4-1BB / TNFRSF9 Stable Cell Line was red line, Negative control HEK293 cells was grey line(QC tested).

Protocol

Cell functional activity verified by FACS and cell-based assay

Flow Cytometry assay shows that Human 4-1BB Protein, Mouse IgG2a Fc Tag (Cat. No. 41B-H5256) can bind to 293T cells overexpressing Human 4-1BBL. The concentration of 4-1BB used is 0.03 μg/mL (Routinely tested).

Protocol

Human CD40 Ligand, His,Flag Tag (Cat. No. CDL-H52Db) stimulates secretion of IL-6 by human B cells. The ED50 for this effect is 18.76-19.45 ng/mL in the presence of 5 ng/mL of Recombinant Human IL4 (Routinely tested).

Protocol

Human B7-H3, His Tag (Cat. No. B73-H52E2) inhibits Anti-CD3-induced proliferation of PBMC. The EC50 for this effect is 2.24-3.36 μg/mL (Routinely tested).

Protocol

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