Committed to providing comprehensive support for global drug development

Tumor cells can evade recognition and elimination by the body's immune system by utilizing immune checkpoint receptors; consequently, blocking these receptors holds promise as a broadly effective strategy for tumor immunotherapy. Although anti-PD-1/PD-L1 antibodies—much like anti-CTLA-4 antibodies—represent a relatively mature class of therapeutics, their overall efficacy in patients remains limited due to the prevalence of drug resistance. Thus, the identification of novel targets for tumor immunotherapy has become a matter of urgent necessity.

The binding of PD-1 to PD-L1 attenuates T cell-mediated immune surveillance, leading to a compromised immune response or even inducing T cell apoptosis. PD-1/PD-L1 inhibitors function by lifting the immunosuppression imposed on anti-tumor T cells, thereby promoting T cell proliferation, facilitating their infiltration into the tumor microenvironment, and ultimately eliciting an anti-tumor immune response. Furthermore, tumor cells can suppress macrophage-mediated phagocytosis by expressing CD47, which interacts with SIRPα receptors present on the surface of macrophages. Recent studies have also revealed that macrophages can similarly suppress their own phagocytic activity through the expression of PD-1, which interacts with PD-L1 expressed by tumor cells. Compared to antibodies, therapeutic peptides offer superior penetration into tumor tissues and are more amenable to synthesis, making them compelling candidates for development as immune checkpoint inhibitors. Consequently, the rational design of peptides capable of dually blocking both the PD-1/PD-L1 and CD47/SIRPα pathways holds significant potential to synergistically enhance the efficacy of anti-tumor immunotherapy.

CD47 & PD-L1 Dual-Target Cells: A foundational cell line engineered to exhibit high-level expression of both human CD47 and PD-L1.

Cell Passage Procedures

1.This cell line grows in suspension.
2.Upon receipt, cells should be thawed immediately or stored in liquid nitrogen until use.
3.Before thawing, pre-warm the water bath and culture medium to 37 °C, and prepare a small amount of dry ice.
4.Remove the cryovial from storage and transport it to the cell culture laboratory on dry ice.
5.Rapidly thaw the cells in a 37 °C water bath. Once the cells are completely thawed, spray the cryovial with 70% ethanol for disinfection and transfer it to a biosafety cabinet.
6.Add 10 mL of pre-warmed culture medium into a 15 mL centrifuge tube. Transfer the contents of the cryovial into the tube and centrifuge at 1000 rpm for 5 minutes.
7.Carefully discard the supernatant. Resuspend the cell pellet in 5 mL of pre-warmed culture medium by gentle pipetting. Immediately perform cell counting and adjust the cell density to 3–6 × 10⁵ cells/mL based on the counting results, then transfer the cells into a culture flask.
8.Count the cells every 1–2 days. When the cell density exceeds 1 × 10⁶ cells/mL, passage the cells promptly or add fresh culture medium. Maintain the cell density between 2 × 10⁵ and 1 × 10⁶ cells/mL.

Suspension Cell Cryopreservation Procedure:

1.Collect 8 × 10⁶ cells, centrifuge, and discard the supernatant.
2.Add 1 mL of cell freezing medium (90% FBS + 10% DMSO) and gently pipette to mix thoroughly. Transfer the suspension into a cryovial.
3.Immediately place the cryovial into a controlled-rate freezing container (Nalgene 5100-0001), fill with isopropanol up to the indicated level, and store at −80 °C.
4.After 24 hours, transfer the cryovial to liquid nitrogen for long-term storage.