Other β-glucan–recognizing pattern recognition receptors

β-glucan–recognizing pattern recognition receptors (PRRs) are a diverse set of immune receptors that identify β-glucans, which are essential carbohydrate components of fungal cell walls and certain plants (Brown GD, Nat Rev Immunol 2006). While Dectin-1 (CLEC7A) is the most prominent member of this group, other receptors such as Complement Receptor 3 (CR3/CD11b-CD18), Lactosylceramide (LacCer), and Scavenger Receptors (e.g., SCARF1, CD36) also play vital roles in sensing these polysaccharides (Ross GD, J Immunol 1985; Sato T, J Biol Chem 2006). These receptors are predominantly expressed on innate immune cells, including macrophages, neutrophils, and natural killer cells, where they initiate signaling cascades that lead to phagocytosis, respiratory burst, and the secretion of pro-inflammatory cytokines. In clinical development, these receptors are targeted by β-glucan-derived compounds like Imprime PGG to enhance the host's anti-tumor or anti-fungal immune responses (Goodridge HS, Immunol Rev 2009). For example, β-glucans can prime CR3 on neutrophils to kill tumor cells coated with complement-fixing antibodies. However, the therapeutic use of these pathways is complicated by the structural diversity of β-glucans and the overlapping functions of the various receptors involved. Understanding the specific contributions of these "other" receptors, such as EphA2 in fungal recognition, is crucial for the design of next-generation immunomodulators (Swidergall M, PLoS Pathog 2018).

Other names

Non-Dectin-1 beta-glucan receptorsBeta-glucan binding proteinsComplement receptor 3 (as a beta-glucan receptor)Lactosylceramide (as a beta-glucan receptor)Scavenger receptor class F member 1 (SCARF1)Ephrin type-A receptor 2 (EphA2)

Agonism of innate immune receptors to enhance phagocytosis, oxidative burst, and cytokine production via Syk or Raf-1 signaling pathways.