CD40 Ligand Chimeric Monoclonal Antibody (Clone IDEC-131 (Toralizumab))

CD40 ligand (CD40L) is a type II transmembrane protein and member of the TNF superfamily encoded by CD40LG in humans.¹ It is expressed primarily by activated T cells, as well as activated B cells and platelets and, under inflammatory conditions, can be induced in natural killer (NK) cells, mast cells, basophils, and monocytes. CD40L trimerizes to engage its receptor, CD40, on various cells, including B cells, dendritic cells, monocytes, platelets, macrophages, endothelial cells, and myoblasts, to induce cell type-specific signaling and activities. Soluble CD40L (sCD40L) is produced by proteolytic cleavage of CD40L at the cell surface and is found in the circulation.^2,3 sCD40L retains its ability to trimerize and bind to CD40, indicating CD40L can act as a cytokine.² CD40L stimulates the proliferation of, and increases IgE secretion in, isolated human tonsil B cells.⁴ Immune complexes targeting CD40L induce thrombocytopenia and thrombosis in transgenic mice expressing the gene encoding the human IgG receptor (FCGR2A).⁵ Mutations in CD40LG are associated with X-linked immunodeficiency with hyper-IgM (HIGMX-1), a disorder characterized by an immunoglobulin isotype switch defect, increased serum IgM levels, ineffective T cell-B cell cooperation, and recurrent bacterial infections.⁶ Cayman’s CD40 Ligand Chimeric Monoclonal Antibody (Clone IDEC-131 (Toralizumab)) was produced recombinantly from the original gp39/CD40 antibody sequence and can be used for immunofluorescence (IF). The gp39/CD40 antibody was generated by immunizing mice with a soluble fusion protein of human gp39-CD8.⁷

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1. Elgueta, R., Benson, M.J., de Vries, V.C., et al. Molecular mechanism and function of CD40/CD40L engagement in the immune system. Immunol. Rev. 229(1), 152-172 (2009).

2. van Kooten, C., and Banchereau, J. CD40-CD40 Ligand. J. Leukoc. Biol. 67(1), 2-17 (2000).

3. Doublier, S., Zennaro, C., Musante, L., et al. Soluble CD40 ligand directly alters glomerular permeability and may act as a circulating permeability factor in FSGS. PLoS One 12(11), e0188045 (2017).

4. Spriggs, M.K., Armitage, R.J., Strockbine, L., et al. Recombinant human CD40 ligand stimulates B cell proliferation and immunoglobulin E secretion. J. Exp. Med. 176(6), 1543-1550 (1992).

5. Robles-Carrillo, L., Meyer, T., Hatfield, M., et al. Anti-CD40L immune complexes potently activate platelets in vitro and cause thrombosis in FCGR2A transgenic mice. J. Immunol. 185(3), 1577-1583 (2010).

6. Macchi, P., Villa, A., Strina, D., et al. Characterization of nine novel mutations in the CD40 ligand gene in patients with X-linked hyper IgM syndrome of various ancestry. Am. J. Hum. Genet. 56(4), 898-906 (1995).

7. Black, A., Hanna, N., Padlan, E.A., et al. Humanized antibodies to human GP39, compositions containing thereof. (1999).