Which cell type can kill Leishmania promastigotes via NETosis?

Which cell type can kill Leishmania promastigotes via NETosis?

• A. Eosinophils
• B. Neutrophils
• C. Macrophages
• D. Dendritic cells

Answer: (B)

NETosis is a defense mechanism where neutrophils release their DNA to form extracellular traps that ensnare and kill pathogens outside of cells. This mechanism is especially effective against motile, extracellular forms like Leishmania promastigotes that are present in tissues after transmission. The NETs are studded with antimicrobial proteins—such as elastase and myeloperoxidase—that kill or inhibit the parasite while it is trapped. Other immune cells, like macrophages and dendritic cells, kill parasites primarily through phagocytosis and intracellular destruction rather than NET formation. Eosinophils can attack parasites too, but NETosis is a hallmark neutrophil process. Thus, neutrophils are the cell type capable of killing Leishmania promastigotes via NETosis.

NETosis is a defense mechanism where neutrophils release their DNA to form extracellular traps that ensnare and kill pathogens outside of cells. This mechanism is especially effective against motile, extracellular forms like Leishmania promastigotes that are present in tissues after transmission. The NETs are studded with antimicrobial proteins—such as elastase and myeloperoxidase—that kill or inhibit the parasite while it is trapped. Other immune cells, like macrophages and dendritic cells, kill parasites primarily through phagocytosis and intracellular destruction rather than NET formation. Eosinophils can attack parasites too, but NETosis is a hallmark neutrophil process. Thus, neutrophils are the cell type capable of killing Leishmania promastigotes via NETosis.