Which receptor on immune cells recognizes fungal beta-glucans?

Which receptor on immune cells recognizes fungal beta-glucans?

• A. Dectin-1
• B. TLR4
• C. CR3
• D. NOD2

Answer: (A)

Fungal beta-glucans are a major pattern found in fungal cell walls, and their detection by the immune system is mainly carried out by a specific receptor on innate immune cells. This receptor, Dectin-1, is a C-type lectin expressed on macrophages, dendritic cells, and neutrophils. When Dectin-1 binds beta-1,3/1,6-glucans, it triggers a signaling cascade through Syk kinase and the CARD9–BCL10–MALT1 axis, leading to the production of proinflammatory cytokines and chemokines, enhanced phagocytosis, and generation of reactive oxygen species to kill the fungi. This receptor often works in concert with Toll-like receptors to amplify the antifungal response. TLR4 mainly recognizes lipopolysaccharide from Gram-negative bacteria, not beta-glucans. CR3 can aid in phagocytosis of some particles and participate in immune recognition, but it is not the primary receptor for beta-glucan binding. NOD2 detects bacterial peptidoglycan components, such as muramyl dipeptide, and is not specialized for beta-glucans.

Fungal beta-glucans are a major pattern found in fungal cell walls, and their detection by the immune system is mainly carried out by a specific receptor on innate immune cells. This receptor, Dectin-1, is a C-type lectin expressed on macrophages, dendritic cells, and neutrophils. When Dectin-1 binds beta-1,3/1,6-glucans, it triggers a signaling cascade through Syk kinase and the CARD9–BCL10–MALT1 axis, leading to the production of proinflammatory cytokines and chemokines, enhanced phagocytosis, and generation of reactive oxygen species to kill the fungi. This receptor often works in concert with Toll-like receptors to amplify the antifungal response.

TLR4 mainly recognizes lipopolysaccharide from Gram-negative bacteria, not beta-glucans. CR3 can aid in phagocytosis of some particles and participate in immune recognition, but it is not the primary receptor for beta-glucan binding. NOD2 detects bacterial peptidoglycan components, such as muramyl dipeptide, and is not specialized for beta-glucans.