ASP7266, a Novel Antibody against Human Thymic Stromal Lymphopoietin Receptor for the Treatment of Allergic Diseases.

Thymic stromal lymphopoietin (TSLP), positioned at the top of the inflammatory cascade, is a key regulator that enhances allergic inflammatory responses by activating T helper type 2 cells, Group 2 innate lymphoid cells (ILC2), and myeloid dendritic cells (mDCs) via the TSLP receptor (TSLPR). We evaluated the inhibitory effects of ASP7266, a novel recombinant fully human IgG monoclonal antibody against TSLPR, on TSLP signaling and inflammation. The inhibitory effects of ASP7266 and the control antibody tezepelumab on TSLP and TSLPR interactions were investigated using a proliferation assay with TSLP stimulation and a chemokine production assay.

Mechanism analysis of long-term graft survival by monocarboxylate transporter-1 inhibition.

Background: Monocarboxylate transporter (MCT)-1, a member of a family of molecules, transports monocarboxylates such as lactate. Inhibiting MCT-1 leads to long-term graft survival in rodent heart transplantation and induces tolerance. We evaluated an MCT-1 inhibitor, AS2495674, in a rat heart transplant model and analyzed its underlying mechanism.

Species selectivity of small-molecular antagonists for the CCR5 chemokine receptor.

The species selectivity of four structurally different compounds, SCH-351125, E-913, TAK-779 and UK-427857 has been examined using cloned human, rhesus, and mouse CCR5 receptors. SCH-351125 and E-913 potently inhibited the binding of [125I]-CCL3 to human CCR5, but their inhibitory activities against rhesus CCR5 were more than 10-fold weaker. In contrast, TAK-779 and UK-427857 inhibited binding to human and rhesus CCR5 with similar potency.

Structural basis for the interaction of CCR5 with a small molecule, functionally selective CCR5 agonist.

The chemokine receptor CCR5 is an attractive target for HIV-1 drug development, as individuals whose cells lack surface CCR5 expression are highly resistant to HIV-1 infection. CCR5 ligands, such as CCL5/RANTES, effectively inhibit HIV-1 infection by competing for binding opportunities to the CCR5 and inducing its internalization. However, the inherent proinflammatory activity of the chemotactic response of CCR5 ligands has limited their clinical use.

Transgenic mouse expressing human CCR5 as a model for in vivo assessments of human selective CCR5 antagonists.

The species selectivity of receptor antagonists often hinders their preclinical assessment in vivo. In order to evaluate human selective CC chemokine receptor type 5 (CCR5) antagonists in vivo, we generated human CCR5 transgenic mice that expressed the transgene on both peripheral blood leukocytes as well as thymocytes. The selective CCR5 ligand CC chemokine ligand 4 (CCL4)/macrophage inflammatory protein (MIP)-1beta induced the chemotaxis of thymocytes that had been derived from the transgenic mice, but not from littermate mice, suggesting that the human CCR5 expressed in the transgenic mice were functional.